[ { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n1\n3\n\n\n\nx\n3\n\n\n+\n\n\nx\n2\n\n\n\n15\nx\n+\n17\n.

\n
\n

The graph of \nf\n has horizontal tangents at the points where \nx\n = \na\n and \nx\n = \nb\n, \na\n < \nb\n.

\n
\n

Find \n\nf\n\n\n\n(\nx\n)\n\n.

\n
[2]
\n
a.
\n
\n

Find the value of \na\n and the value of \nb\n.

\n
[3]
\n
b.
\n
\n

Sketch the graph of \ny\n=\n\nf\n\n\n\n(\nx\n)\n\n.

\n
[1]
\n
c.i.
\n
\n

Hence explain why the graph of \nf\n has a local maximum point at \nx\n=\na\n.

\n
[1]
\n
c.ii.
\n
\n

Find \n\nf\n\n\n\n(\nb\n)\n\n.

\n
[3]
\n
d.i.
\n
\n

Hence, use your answer to part (d)(i) to show that the graph of \nf\n has a local minimum point at \nx\n=\nb\n.

\n
[1]
\n
d.ii.
\n
\n

The normal to the graph of \nf\n at \nx\n=\na\n and the tangent to the graph of \nf\n at \nx\n=\nb\n intersect at the point (\np\n, \nq\n) .

\n

 

\n

Find the value of \np\n and the value of \nq\n.

\n
[5]
\n
e.
\n
", "Markscheme": "
\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n\nx\n2\n\n\n+\n2\nx\n\n15\n     (M1)A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

correct reasoning that \n\nf\n\n\n\n(\nx\n)\n\n=\n0\n (seen anywhere)    (M1)

\n

\n\n\nx\n2\n\n\n+\n2\nx\n\n15\n=\n0\n

\n

valid approach to solve quadratic        M1

\n

\n\n(\n\nx\n\n3\n\n)\n\n\n(\n\nx\n+\n5\n\n)\n\n, quadratic formula

\n

correct values for \nx\n

\n

3, −5

\n

correct values for \na\n and \nb\n

\n

\na\n = −5 and \nb\n = 3        A1

\n

[3 marks]

\n
b.
\n
\n

      A1

\n

[1 mark]

\n
c.i.
\n
\n

first derivative changes from positive to negative at  \nx\n=\na\n      A1

\n

so local maximum at \nx\n=\na\n     AG

\n

[1 mark]

\n
c.ii.
\n
\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n2\nx\n+\n2\n     A1

\n

substituting their \nb\n into their second derivative     (M1)

\n

\n\nf\n\n\n\n(\n3\n)\n\n=\n2\n×\n3\n+\n2\n

\n

\n\nf\n\n\n\n(\nb\n)\n\n=\n8\n     (A1)

\n

[3 marks]

\n
d.i.
\n
\n

\n\nf\n\n\n\n(\nb\n)\n\n is positive so graph is concave up      R1

\n

so local minimum at \nx\n=\nb\n       AG

\n

[1 mark]

\n
d.ii.
\n
\n

normal to \nf\n at \nx\n=\na\n is \nx\n = −5 (seen anywhere)          (A1)

\n

attempt to find \ny\n-coordinate at their value of \nb\n          (M1)

\n

\nf\n\n(\n3\n)\n\n=\n −10       (A1)

\n

tangent at \nx\n=\nb\n has equation \ny\n = −10 (seen anywhere)         A1

\n

intersection at (−5, −10)

\n

\np\n = −5 and \nq\n = −10        A1

\n

[5 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "SPM.1.SL.TZ0.8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Adam sets out for a hike from his camp at point A. He hikes at an average speed of 4.2 km/h for 45 minutes, on a bearing of 035° from the camp, until he stops for a break at point B.

\n
\n

\n

Adam leaves point B on a bearing of 114° and continues to hike for a distance of 4.6‌ km until he reaches point C.

\n

\n
\n

Adam’s friend Jacob wants to hike directly from the camp to meet Adam at point C .

\n
\n

Find the distance from point A to point B.

\n
[2]
\n
a.
\n
\n

Show that \n\nA\n\n\n\nB\n\n\n\n\n\nC\n\n is 101°.

\n
[2]
\n
b.i.
\n
\n

Find the distance from the camp to point C.

\n
[3]
\n
b.ii.
\n
\n

Find \n\nB\n\n\n\nC\n\n\n\n\n\nA\n\n.

\n
[3]
\n
c.
\n
\n

Find the bearing that Jacob must take to point C.

\n
[3]
\n
d.
\n
\n

Jacob hikes at an average speed of 3.9 km/h.

\n

Find, to the nearest minute, the time it takes for Jacob to reach point C.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

\n\n\n4.2\n\n\n60\n\n\n×\n45\n       A1

\n

AB = 3.15 (km)      A1

\n

[2 marks]

\n
a.
\n
\n

66° or (180 − 114)       A1

\n

35 + 66      A1

\n

\n\nA\n\n\n\nB\n\n\n\n\n\nC\n\n = 101°       AG

\n

[2 marks]

\n
b.i.
\n
\n

attempt to use cosine rule      (M1)

\n

AC2 = 3.152 + 4.62 − 2 × 3.15 × 4.6 cos 101° (or equivalent)       A1

\n

AC = 6.05 (km)        A1

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

valid approach to find angle BCA       (M1)

\n

eg sine rule

\n

correct substitution into sine rule        A1

\n

eg  \n\n\n\nsin\n\n\n(\n\n\nB\n\n\n\nC\n\n\n\n\n\nA\n\n\n)\n\n\n\n3.15\n\n\n=\n\n\n\nsin\n\n\n\n101\n\n\n\n6.0507\n\n\n\n

\n

\n\nB\n\n\n\nC\n\n\n\n\n\nA\n\n = 30.7°      A1

\n

[3 marks]

\n
c.
\n
\n

\n\nB\n\n\n\nA\n\n\n\n\n\nC\n\n = 48.267 (seen anywhere)      A1

\n

valid approach to find correct bearing      (M1)

\n

eg  48.267 + 35

\n

bearing = 83.3° (accept 083°)      A1

\n

[3 marks]

\n
d.
\n
\n

attempt to use \n\ntime\n\n=\n\n\n\ndistance\n\n\n\n\nspeed\n\n\n\n      M1

\n

\n\n\n6.0507\n\n\n3.9\n\n\n or 0.065768 km/min        (A1)

\n

t = 93 (minutes)       A1

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "SPM.2.SL.TZ0.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The length, X mm, of a certain species of seashell is normally distributed with mean 25 and variance, \n\n\nσ\n2\n\n\n.

\n

The probability that X is less than 24.15 is 0.1446.

\n
\n

A random sample of 10 seashells is collected on a beach. Let Y represent the number of seashells with lengths greater than 26 mm.

\n
\n

Find P(24.15 < X < 25).

\n
[2]
\n
a.
\n
\n

Find \nσ\n, the standard deviation of X.

\n
[3]
\n
b.i.
\n
\n

Hence, find the probability that a seashell selected at random has a length greater than 26 mm.

\n
[2]
\n
b.ii.
\n
\n

Find E(Y).

\n
[3]
\n
c.
\n
\n

Find the probability that exactly three of these seashells have a length greater than 26 mm.

\n
[2]
\n
d.
\n
\n

A seashell selected at random has a length less than 26 mm.

\n

Find the probability that its length is between 24.15 mm and 25 mm.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

attempt to use the symmetry of the normal curve        (M1)

\n

eg   diagram, 0.5 − 0.1446

\n

P(24.15 < X < 25) = 0.3554        A1

\n

[2 marks]

\n
a.
\n
\n

use of inverse normal to find z score      (M1)

\n

z = −1.0598

\n

correct substitution \n\n\n24.15\n\n25\n\nσ\n\n=\n\n1.0598\n       (A1)

\n

\nσ\n = 0.802       A1   

\n

[3 marks]

\n
b.i.
\n
\n

P(X > 26) = 0.106       (M1)A1  

\n

[2 marks]

\n
b.ii.
\n
\n

recognizing binomial probability      (M1)

\n

E(Y) = 10 × 0.10621       (A1)

\n

= 1.06         A1  

\n

[3 marks]

\n
c.
\n
\n

P(Y = 3)        (M1)

\n

= 0.0655        A1  

\n

[2 marks]

\n
d.
\n
\n

recognizing conditional probability        (M1)

\n

correct substitution        A1

\n

\n\n\n0.3554\n\n\n1\n\n0.10621\n\n\n

\n

= 0.398       A1

\n

[3 marks]

\n

 

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "SPM.2.SL.TZ0.8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n\nln\n\n\n5\nx\n\n\nk\nx\n\n\n where \nx\n>\n0\n\nk\n\n\n\n\nR\n\n+\n\n\n.

\n
\n

The graph of \nf\n has exactly one maximum point P.

\n
\n

The second derivative of \nf\n is given by \n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n2\n\n\nln\n\n\n5\nx\n\n3\n\n\nk\n\n\nx\n3\n\n\n\n\n. The graph of \nf\n has exactly one point of inflexion Q.

\n
\n

Show that \n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n1\n\n\nln\n\n\n5\nx\n\n\nk\n\n\nx\n2\n\n\n\n\n.

\n
[3]
\n
a.
\n
\n

Find the x-coordinate of P.

\n
[3]
\n
b.
\n
\n

Show that the x-coordinate of Q is \n\n\n1\n\n5\n\n\n\n\ne\n\n\n\n3\n2\n\n\n\n\n.

\n
[3]
\n
c.
\n
\n

The region R is enclosed by the graph of \nf\n, the x-axis, and the vertical lines through the maximum point P and the point of inflexion Q.

\n

\n

Given that the area of R is 3, find the value of \nk\n.

\n
[7]
\n
d.
\n
", "Markscheme": "
\n

attempt to use quotient rule       (M1)

\n

correct substitution into quotient rule

\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n5\nk\nx\n\n(\n\n\n1\n\n5\nx\n\n\n\n)\n\n\nk\n\n\nln\n\n\n5\nx\n\n\n\n\n\n\n(\n\nk\nx\n\n)\n\n\n2\n\n\n\n\n (or equivalent)        A1

\n

\n=\n\n\nk\n\nk\n\n\nln\n\n\n5\nx\n\n\n\n\nk\n2\n\n\n\n\nx\n2\n\n\n\n\n, \n\n(\n\nk\n\n\n\n\nR\n\n+\n\n\n\n)\n\n        A1

\n

\n=\n\n\n1\n\n\nln\n\n\n5\nx\n\n\nk\n\n\nx\n2\n\n\n\n\n        AG

\n

[3 marks]

\n
a.
\n
\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n0\n     M1

\n

\n\n\n1\n\n\nln\n\n\n5\nx\n\n\nk\n\n\nx\n2\n\n\n\n\n=\n0\n

\n

\n\nln\n\n\n5\nx\n=\n1\n      (A1)

\n

\nx\n=\n\n\ne\n\n5\n\n      A1

\n

[3 marks]

\n
b.
\n
\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n0\n    M1

\n

\n\n\n2\n\n\nln\n\n\n5\nx\n\n3\n\n\nk\n\n\nx\n3\n\n\n\n\n=\n0\n

\n

\n\nln\n\n\n5\nx\n=\n\n3\n2\n\n     A1

\n

\n5\nx\n=\n\n\n\ne\n\n\n\n3\n2\n\n\n\n\n     A1

\n

so the point of inflexion occurs at \nx\n=\n\n\n1\n\n5\n\n\n\n\ne\n\n\n\n3\n2\n\n\n\n\n     AG

\n

[3 marks]

\n
c.
\n
\n

attempt to integrate   (M1)

\n

\nu\n=\n\nln\n\n\n5\nx\n\n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n\n1\nx\n\n

\n

\n\n\n\n\n\nln\n\n\n5\nx\n\n\nk\nx\n\n\n\n\nd\n\nx\n=\n\n1\nk\n\n\n\nu\n\n\n\nd\n\nu\n     (A1)

\n

EITHER

\n

=\n\n\n\n\nu\n2\n\n\n\n\n2\nk\n\n\n     A1

\n

so \n\n1\nk\n\n\n\n1\n\n\n3\n2\n\n\n\n\nu\n\n\nd\n\nu\n=\n\n\n\n[\n\n\n\n\n\nu\n2\n\n\n\n\n2\nk\n\n\n\n]\n\n1\n\n\n3\n2\n\n\n\n     A1

\n

OR

\n

\n=\n\n\n\n\n\n\n(\n\n\nln\n\n\n5\nx\n\n)\n\n\n2\n\n\n\n\n2\nk\n\n\n     A1

\n

so \n\n\n\n\n\ne\n\n5\n\n\n\n\n\n1\n\n5\n\n\n\n\ne\n\n\n\n3\n2\n\n\n\n\n\n\n\n\n\n\nln\n\n\n5\nx\n\n\nk\nx\n\n\n\n\nd\n\nx\n=\n\n\n[\n\n\n\n\n\n\n\n(\n\n\nln\n\n\n5\nx\n\n)\n\n\n2\n\n\n\n\n2\nk\n\n\n\n]\n\n\n\n\ne\n\n5\n\n\n\n\n\n1\n\n5\n\n\n\n\ne\n\n\n\n3\n2\n\n\n\n\n\n\n     A1

\n

THEN

\n

\n=\n\n1\n\n2\nk\n\n\n\n(\n\n\n9\n4\n\n\n1\n\n)\n\n

\n

\n=\n\n5\n\n8\nk\n\n\n     A1

\n

setting their expression for area equal to 3       M1 

\n

\n\n5\n\n8\nk\n\n\n=\n3\n

\n

\nk\n=\n\n5\n\n24\n\n\n     A1

\n

[7 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "SPM.1.SL.TZ0.9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

The following diagram shows the graph of \ny\n=\nf\n\n(\nx\n)\n\n. The graph has a horizontal asymptote at \ny\n=\n\n1\n. The graph crosses the \nx\n-axis at \nx\n=\n\n1\n and \nx\n=\n1\n, and the \ny\n-axis at \ny\n=\n2\n.

\n

\n

On the following set of axes, sketch the graph of \ny\n=\n\n\n\n[\n\nf\n\n(\nx\n)\n\n\n]\n\n2\n\n\n+\n1\n, clearly showing any asymptotes with their equations and the coordinates of any local maxima or minima.

\n

\n

 

\n
", "Markscheme": "
\n

\n

no \ny\n values below 1        A1

\n

horizontal asymptote at \ny\n=\n2\n with curve approaching from below as \nx\n\n±\n\n        A1

\n

(±1,1) local minima        A1

\n

(0,5) local maximum        A1

\n

smooth curve and smooth stationary points        A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.1.AHL.TZ0.4", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-16-graphing-modulus-equations-and-inequalities" ] }, { "Question": "
\n

A continuous random variable X has the probability density function \nf\n given by

\n

\nf\n\n(\nx\n)\n\n=\n\n{\n\n\n\n\n\n\n\nπ\nx\n\n\n36\n\n\n\nsin\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n\n,\n\n\n\n\n\n0\n\nx\n\n6\n\n\n\n\n\n\n0\n\n,\n\n\n\n\n\n\notherwise\n\n\n\n\n\n\n\n\n.

\n

Find P(0 ≤ X ≤ 3).

\n
", "Markscheme": "
\n

attempting integration by parts, eg

\n

\nu\n=\n\n\nπ\nx\n\n\n36\n\n\n\n,\n\n\n\nd\n\nu\n=\n\nπ\n\n36\n\n\n\nd\n\nx\n\n,\n\n\n\nd\n\nv\n=\n\nsin\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n\nd\n\nx\n\n,\n\n\nv\n=\n\n\n6\nπ\n\n\ncos\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n               (M1)

\n

P(0 ≤ X ≤ 3) \n=\n\nπ\n\n36\n\n\n\n(\n\n\n\n[\n\n\n\n\n6\nx\n\nπ\n\n\ncos\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n\n]\n\n0\n3\n\n+\n\n6\nπ\n\n\n\n0\n3\n\n\n\ncos\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n\n\nd\n\nx\n\n)\n\n (or equivalent)      A1A1

\n

Note: Award A1 for a correct \nu\nv\n and A1 for a correct \n\n\nv\n\n\nd\n\nu\n\n.

\n

attempting to substitute limits       M1

\n

\n\nπ\n\n36\n\n\n\n\n[\n\n\n\n\n6\nx\n\nπ\n\n\ncos\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n\n]\n\n0\n3\n\n=\n0\n       (A1)

\n

so P(0 ≤ X ≤ 3) \n=\n\n1\nπ\n\n\n\n[\n\n\nsin\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n\n]\n\n0\n3\n\n (or equivalent)       A1

\n

\n=\n\n1\nπ\n\n      A1

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.1.AHL.TZ0.7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "ahl-4-14-properties-of-discrete-and-continuous-random-variables" ] }, { "Question": "
\n

The plane П has the Cartesian equation  2 x + y + 2 z = 3

\n

The line L has the vector equation r = ( 3 5 1 ) + μ ( 1 2 p ) , μ , p R . The acute angle between the line L and the plane П is 30°.

\n

Find the possible values of p .

\n
", "Markscheme": "
\n

recognition that the angle between the normal and the line is 60° (seen anywhere)       R1

\n

attempt to use the formula for the scalar product       M1

\n

cos 60° = | ( 2 1 2 ) ( 1 2 p ) | 9 × 1 + 4 + p 2      A1

\n

1 2 = | 2 p | 3 5 + p 2       A1

\n

3 5 + p 2 = 4 | p |

\n

attempt to square both sides         M1

\n

9 ( 5 + p 2 ) = 16 p 2 7 p 2 = 45

\n

p = ± 3 5 7  (or equivalent)       A1A1

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.1.AHL.TZ0.8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\n\n\ne\n\n\n2\nx\n\n\n\n\n6\n\n\n\ne\n\nx\n\n\n+\n5\n\n,\n\n\n\nx\n\n\nR\n\n\n,\n\n\n\nx\n\na\n. The graph of \ny\n=\nf\n\n(\nx\n)\n\n is shown in the following diagram.

\n

\n
\n

Find the largest value of \na\n such that \nf\n has an inverse function.

\n
[3]
\n
a.
\n
\n

For this value of \na\n, find an expression for \n\n\nf\n\n\n1\n\n\n\n\n(\nx\n)\n\n, stating its domain.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

attempt to differentiate and set equal to zero       M1

\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n2\n\n\n\ne\n\n\n2\nx\n\n\n\n\n6\n\n\n\ne\n\nx\n\n\n=\n2\n\n\n\ne\n\nx\n\n\n\n(\n\n\n\n\ne\n\nx\n\n\n\n3\n\n)\n\n=\n0\n       A1

\n

minimum at \nx\n=\n\nln\n\n\n3\n

\n

\na\n=\n\nln\n\n\n3\n       A1

\n

[3 marks]

\n
a.
\n
\n

Note: Interchanging \nx\n and \ny\n can be done at any stage.

\n

\ny\n=\n\n\n\n(\n\n\n\n\ne\n\nx\n\n\n\n3\n\n)\n\n2\n\n\n\n4\n     (M1)

\n

\n\n\n\ne\n\nx\n\n\n\n3\n=\n±\n\ny\n+\n4\n\n     A1

\n

as \nx\n\n\nln\n\n\n3\n\nx\n=\n\nln\n\n\n(\n\n3\n\n\ny\n+\n4\n\n\n)\n\n       R1

\n

so \n\n\nf\n\n\n1\n\n\n\n\n(\nx\n)\n\n=\n\nln\n\n\n(\n\n3\n\n\nx\n+\n4\n\n\n)\n\n    A1

\n

domain of \n\n\nf\n\n\n1\n\n\n\n is \nx\n\n\nR\n\n\n\n4\n\nx\n<\n5\n    A1

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.1.AHL.TZ0.9", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-14-odd-and-even-functions-self-inverse-inverse-and-domain-restriction" ] }, { "Question": "
\n

Consider a function f , such that f(x)=5.8sin(π6(x+1))+b, 0 ≤  x  ≤ 10,  b R .

\n
\n

The function \nf\n has a local maximum at the point (2, 21.8) , and a local minimum at (8, 10.2).

\n
\n

A second function \ng\n is given by \ng\n(\nx\n)\n=\np\n\n\nsin\n\n\n(\n\n\n\n2\nπ\n\n9\n\n\n(\n\nx\n\n3.75\n\n)\n\n\n)\n\n+\nq\n,  0 ≤ \nx\n ≤ 10;  \np\n\nq\n\n\nR\n\n.

\n

The function \ng\n passes through the points (3, 2.5) and (6, 15.1).

\n
\n

Find the period of \nf\n.

\n
[2]
\n
a.
\n
\n

Find the value of \nb\n.

\n
[2]
\n
b.i.
\n
\n

Hence, find the value of \nf\n(6).

\n
[2]
\n
b.ii.
\n
\n

Find the value of \np\n and the value of \nq\n.

\n
[5]
\n
c.
\n
\n

Find the value of \nx\n for which the functions have the greatest difference.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

correct approach      A1

\n

eg   \n\nπ\n6\n\n=\n\n\n2\nπ\n\n\np\ne\nr\ni\no\nd\n\n\n  (or equivalent)

\n

period = 12        A1

\n

[2 marks]

\n

 

\n
a.
\n
\n

valid approach      (M1)

\n

eg  \n\n\n\nmax\n\n+\n\nmin\n\n\n2\n\n\n\nb\n=\n\nmax\n\n\n\namplitude\n\n

\n

\n\n\n21.8\n+\n10.2\n\n2\n\n, or equivalent

\n

\nb\n = 16        A1

\n

[2 marks]

\n

 

\n
b.i.
\n
\n

attempt to substitute into their function     (M1)

\n

\n5.8\n\n\nsin\n\n\n(\n\n\nπ\n6\n\n\n(\n\n6\n+\n1\n\n)\n\n\n)\n\n+\n16\n

\n

\nf\n(6) = 13.1        A1

\n

[2 marks]

\n

 

\n
b.ii.
\n
\n

valid attempt to set up a system of equations    (M1)

\n

two correct equations        A1

\n

\np\n\n\nsin\n\n\n(\n\n\n\n2\nπ\n\n9\n\n\n(\n\n3\n\n3.75\n\n)\n\n\n)\n\n+\nq\n=\n2.5\n,  \np\n\n\nsin\n\n\n(\n\n\n\n2\nπ\n\n9\n\n\n(\n\n6\n\n3.75\n\n)\n\n\n)\n\n+\nq\n=\n15.1\n

\n

valid attempt to solve system   (M1)

\n

\np\n = 8.4; \nq\n = 6.7        A1A1

\n

[5 marks]

\n

 

\n
c.
\n
\n

attempt to use \n\n|\n\nf\n(\nx\n)\n\ng\n(\nx\n)\n\n|\n\n to find maximum difference  (M1)

\n

\nx\n = 1.64        A1

\n

 

\n

[2 marks]

\n

 

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "SPM.2.SL.TZ0.9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

Let the roots of the equation \n\n\nz\n3\n\n\n=\n\n3\n+\n\n3\n\n\ni\n\n be \nu\n\nv\n and \nw\n.

\n
\n

On an Argand diagram, \nu\n\nv\n and \nw\n are represented by the points U, V and W respectively.

\n
\n

Express  3 + 3 i in the form  r e i θ , where  r > 0 and π < θ π .

\n
[5]
\n
a.
\n
\n

Find  u v and  w  expressing your answers in the form  r e i θ , where  r > 0 and  π < θ π .

\n
[5]
\n
b.
\n
\n

Find the area of triangle UVW.

\n
[4]
\n
c.
\n
\n

By considering the sum of the roots u v and  w , show that

\n

cos 5 π 18 + cos 7 π 18 + cos 17 π 18 = 0 .

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

attempt to find modulus      (M1)

\n

r = 2 3 ( = 12 )       A1

\n

attempt to find argument in the correct quadrant      (M1)

\n

θ = π + arctan ( 3 3 )       A1

\n

= 5 π 6       A1

\n

3 + 3 i = 12 e 5 π i 6 ( = 2 3 e 5 π i 6 )

\n

[5 marks]

\n
a.
\n
\n

attempt to find a root using de Moivre’s theorem      M1

\n

12 1 6 e 5 π i 18        A1

\n

attempt to find further two roots by adding and subtracting  2 π 3 to the argument    M1

\n

12 1 6 e 7 π i 18        A1

\n

12 1 6 e 17 π i 18        A1

\n

Note: Ignore labels for u v and  w at this stage.

\n

 

\n

[5 marks]

\n
b.
\n
\n

METHOD 1
attempting to find the total area of (congruent) triangles UOV, VOW and UOW        M1

\n

Area = 3 ( 1 2 ) ( 12 1 6 ) ( 12 1 6 ) sin 2 π 3       A1A1

\n

Note: Award A1 for  ( 12 1 6 ) ( 12 1 6 )  and A1 for  sin 2 π 3

\n

= 3 3 4 ( 12 1 3 )  (or equivalent)     A1

\n

 

\n

METHOD 2

\n

UV2  = ( 12 1 6 ) 2 + ( 12 1 6 ) 2 2 ( 12 1 6 ) ( 12 1 6 ) cos 2 π 3  (or equivalent)     A1

\n

UV  = 3 ( 12 1 6 )  (or equivalent)     A1

\n

attempting to find the area of UVW using Area =  1 2  × UV × VW × sin  α  for example        M1

\n

Area  = 1 2 ( 3 × 12 1 6 ) ( 3 × 12 1 6 ) sin π 3

\n

= 3 3 4 ( 12 1 3 )  (or equivalent)     A1

\n

 

\n

[4 marks]

\n
c.
\n
\n

u + v + w = 0     R1

\n

12 1 6 ( cos ( 7 π 18 ) + i sin ( 7 π 18 ) + cos 5 π 18 + i sin 5 π 18 + cos 17 π 18 + i sin 17 π 18 ) = 0      A1

\n

consideration of real parts       M1

\n

12 1 6 ( cos ( 7 π 18 ) + cos 5 π 18 + cos 17 π 18 ) = 0

\n

cos ( 7 π 18 ) = cos 17 π 18  explicitly stated      A1

\n

cos 5 π 18 + cos 7 π 18 + cos 17 π 18 = 0      AG

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "SPM.1.AHL.TZ0.11", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

The following table below shows the marks scored by seven students on two different mathematics tests.

\n

\n

Let L1 be the regression line of x on y. The equation of the line L1 can be written in the form x = ay + b.

\n
\n

Let L2 be the regression line of y on x. The lines L1 and L2 pass through the same point with coordinates (p , q).

\n
\n

Find the value of a and the value of b.

\n
[2]
\n
a.
\n
\n

Find the value of p and the value of q.

\n
[3]
\n
b.
\n
\n

Jennifer was absent for the first test but scored 29 marks on the second test. Use an appropriate regression equation to estimate Jennifer’s mark on the first test.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

a = 1.29 and b = −10.4      A1A1

\n

[2 marks]

\n
a.
\n
\n

recognising both lines pass through the mean point       (M1)

\n

p = 28.7, q = 30.3       A2

\n

[3 marks]

\n
b.
\n
\n

substitution into their \nx\n on \ny\n equation        (M1)

\n

\nx\n = 1.29082(29) − 10.3793

\n

\nx\n = 27.1      A1

\n

Note: Accept 27.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "SPM.2.AHL.TZ0.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n.

\n
\n

Find the first two derivatives of \nf\n\n(\nx\n)\n\n and hence find the Maclaurin series for \nf\n\n(\nx\n)\n\n up to and including the \n\n\nx\n2\n\n\n term.

\n
[8]
\n
a.
\n
\n

Show that the coefficient of \n\n\nx\n3\n\n\n in the Maclaurin series for \nf\n\n(\nx\n)\n\n is zero.

\n
[4]
\n
b.
\n
\n

Using the Maclaurin series for \n\narctan\n\n\nx\n and \n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n, find the Maclaurin series for \n\narctan\n\n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n up to and including the \n\n\nx\n3\n\n\n term.

\n
[6]
\n
c.
\n
\n

Hence, or otherwise, find \n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\nf\n\n(\nx\n)\n\n\n1\n\n\n\narctan\n\n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n\n\n.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

attempting to use the chain rule to find the first derivative     M1

\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n(\n\n\ncos\n\n\nx\n\n)\n\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n       A1

\n

attempting to use the product rule to find the second derivative      M1

\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n\n(\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\nx\n\n\nsin\n\n\nx\n\n)\n\n (or equivalent)        A1

\n

attempting to find \nf\n\n(\n0\n)\n\n\n\nf\n\n\n\n(\n0\n)\n\n and \n\nf\n\n\n\n(\n0\n)\n\n       M1

\n

\nf\n\n(\n0\n)\n\n=\n1\n; \n\nf\n\n\n\n(\n0\n)\n\n=\n\n(\n\n\ncos\n\n\n0\n\n)\n\n\n\n\ne\n\n\n\nsin\n\n\n0\n\n\n\n=\n1\n\n\nf\n\n\n\n(\n0\n)\n\n=\n\n\n\ne\n\n\n\nsin\n\n\n0\n\n\n\n\n(\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\n0\n\n\nsin\n\n\n0\n\n)\n\n=\n1\n        A1

\n

substitution into the Maclaurin formula \nf\n\n(\nx\n)\n\n=\nf\n\n(\n0\n)\n\n+\nx\n\nf\n\n\n\n(\n0\n)\n\n+\n\n\n\n\nx\n2\n\n\n\n\n2\n\n!\n\n\n\n\nf\n\n\n\n(\n0\n)\n\n+\n\n       M1

\n

so the Maclaurin series for \nf\n\n(\nx\n)\n\n up to and including the \n\n\nx\n2\n\n\n term is \n1\n+\nx\n+\n\n\n\n\nx\n2\n\n\n\n2\n\n      A1

\n

[8 marks]

\n
a.
\n
\n

METHOD 1

\n

attempting to differentiate \n\nf\n\n\n\n(\nx\n)\n\n       M1

\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n(\n\n\ncos\n\n\nx\n\n)\n\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n\n(\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\nx\n\n\nsin\n\n\nx\n\n)\n\n\n\n(\n\n\ncos\n\n\nx\n\n)\n\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n\n(\n\n2\n\n\nsin\n\n\nx\n+\n1\n\n)\n\n (or equivalent)        A2

\n

substituting \nx\n=\n0\n into their \n\nf\n\n\n\n(\nx\n)\n\n       M1

\n

\n\nf\n\n\n\n(\n0\n)\n\n=\n1\n\n(\n\n1\n\n0\n\n)\n\n\n1\n\n(\n\n0\n+\n1\n\n)\n\n=\n0\n

\n

so the coefficient of \n\n\nx\n3\n\n\n in the Maclaurin series for \nf\n\n(\nx\n)\n\n is zero    AG

\n

 

\n

METHOD 2

\n

substituting \n\n\nsin\n\n\nx\n\n into the Maclaurin series for \n\n\n\ne\n\nx\n\n\n       (M1)

\n

\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n=\n1\n+\n\nsin\n\n\nx\n+\n\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nx\n\n\n2\n\n!\n\n\n\n+\n\n\n\nsi\n\n\n\n\nn\n\n3\n\n\n\nx\n\n\n3\n\n!\n\n\n\n+\n\n

\n

substituting Maclaurin series for \n\n\nsin\n\n\nx\n\n       M1

\n

\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n=\n1\n+\n\n(\n\nx\n\n\n\n\n\nx\n3\n\n\n\n\n3\n\n!\n\n\n\n+\n\n\n)\n\n+\n\n\n\n\n\n\n(\n\nx\n\n\n\n\n\nx\n3\n\n\n\n\n3\n\n!\n\n\n\n+\n\n\n)\n\n\n2\n\n\n\n\n2\n\n!\n\n\n\n+\n\n\n\n\n\n\n(\n\nx\n\n\n\n\n\nx\n3\n\n\n\n\n3\n\n!\n\n\n\n+\n\n\n)\n\n\n3\n\n\n\n\n3\n\n!\n\n\n\n+\n\n     A1

\n

coefficient of \n\n\nx\n3\n\n\n is \n\n\n1\n\n3\n\n!\n\n\n\n+\n\n1\n\n3\n\n!\n\n\n\n=\n0\n     A1

\n

so the coefficient of \n\n\nx\n3\n\n\n in the Maclaurin series for \nf\n\n(\nx\n)\n\n is zero    AG

\n

 

\n

[4 marks]

\n
b.
\n
\n

substituting \n3\nx\n into the Maclaurin series for \n\n\n\ne\n\nx\n\n\n       M1

\n

\n\n\n\ne\n\n\n3\nx\n\n\n\n=\n1\n+\n3\nx\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n2\n\n\n\n\n2\n\n!\n\n\n\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n3\n\n\n\n\n3\n\n!\n\n\n\n+\n\n      A1

\n

substituting \n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n into the Maclaurin series for \n\narctan\n\n\nx\n    M1

\n

\n\narctan\n\n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n=\n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n\n\n\n\n\n\n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n\n3\n\n\n\n3\n\n+\n\n\n\n\n\n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n\n5\n\n\n\n5\n\n\n\n

\n

\n=\n\n(\n\n3\nx\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n2\n\n\n\n\n2\n\n!\n\n\n\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n3\n\n\n\n\n3\n\n!\n\n\n\n+\n\n\n)\n\n\n\n\n\n\n\n\n(\n\n3\nx\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n2\n\n\n\n\n2\n\n!\n\n\n\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n3\n\n\n\n\n3\n\n!\n\n\n\n+\n\n\n)\n\n\n3\n\n\n\n3\n\n+\n\n    A1

\n

selecting correct terms from above      M1

\n

\n=\n\n(\n\n3\nx\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n2\n\n\n\n\n2\n\n!\n\n\n\n+\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n3\n\n\n\n\n3\n\n!\n\n\n\n\n)\n\n\n\n\n\n\n\n\n(\n\n3\nx\n\n)\n\n\n3\n\n\n\n3\n\n

\n

\n=\n3\nx\n+\n\n\n9\n\n\nx\n2\n\n\n\n2\n\n\n\n\n9\n\n\nx\n3\n\n\n\n2\n\n     A1

\n

[6 marks]

\n
c.
\n
\n

METHOD 1

\n

substitution of their series       M1

\n

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\nx\n+\n\n\n\n\nx\n2\n\n\n\n2\n\n+\n\n\n\n3\nx\n+\n\n\n9\n\n\nx\n2\n\n\n\n2\n\n+\n\n\n\n       A1

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\n1\n+\n\nx\n2\n\n+\n\n\n\n3\n+\n\n\n9\nx\n\n2\n\n+\n\n\n\n

\n

\n=\n\n1\n3\n\n     A1

\n

 

\n

METHOD 2

\n

use of l’Hôpital’s rule      M1

\n

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\n\n(\n\n\ncos\n\n\nx\n\n)\n\n\n\n\ne\n\n\n\nsin\n\n\nx\n\n\n\n\n\n\n\n3\n\n\n\ne\n\n\n3\nx\n\n\n\n\n\n1\n+\n\n\n\n\n(\n\n\n\n\ne\n\n\n3\nx\n\n\n\n\n1\n\n)\n\n\n2\n\n\n\n\n\n\n  (or equivalent)    A1

\n

\n=\n\n1\n3\n\n     A1

\n

 

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "SPM.1.AHL.TZ0.12", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-19-maclaurin-series" ] }, { "Question": "
\n

In a city, the number of passengers, X, who ride in a taxi has the following probability distribution.

\n

\n

After the opening of a new highway that charges a toll, a taxi company introduces a charge for passengers who use the highway. The charge is $ 2.40 per taxi plus $ 1.20 per passenger. Let T represent the amount, in dollars, that is charged by the taxi company per ride.

\n
\n

Find E(T).

\n
[4]
\n
a.
\n
\n

Given that Var(X) = 0.8419, find Var(T).

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

attempting to use the expected value formula      (M1)

\n

\n\nE\n\n\n(\nX\n)\n\n=\n\n(\n\n1\n×\n0.60\n\n)\n\n+\n\n(\n\n2\n×\n0.30\n\n)\n\n+\n\n(\n\n3\n×\n0.03\n\n)\n\n+\n\n(\n\n4\n×\n0.05\n\n)\n\n+\n\n(\n\n5\n×\n0.02\n\n)\n\n

\n

\n\nE\n\n\n(\nX\n)\n\n=\n1.59\n($)     (A1)

\n

use of \n\nE\n\n\n(\n\n1.20\nX\n+\n2.40\n\n)\n\n=\n1.20\n\nE\n\n\n(\nX\n)\n\n+\n2.40\n      (M1)

\n

\n\nE\n\n\n(\nT\n)\n\n=\n1.20\n\n(\n\n1.59\n\n)\n\n+\n2.40\n

\n

\n=\n4.31\n($)      A1

\n

 

\n

METHOD 2

\n

attempting to find the probability distribution for T      (M1)

\n

     (A1)

\n

attempting to use the expected value formula       (M1)

\n

\n\nE\n\n\n(\nT\n)\n\n=\n\n(\n\n3.60\n×\n0.60\n\n)\n\n+\n\n(\n\n4.80\n×\n0.30\n\n)\n\n+\n\n(\n\n6.00\n×\n0.03\n\n)\n\n+\n\n(\n\n7.20\n×\n0.05\n\n)\n\n+\n\n(\n\n8.40\n×\n0.02\n\n)\n\n

\n

\n=\n4.31\n($)      A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

METHOD 1

\n

using Var(1.20 X  + 2.40) = (1.20)2 Var(X) with Var(X) = 0.8419      (M1)

\n

Var(T) = 1.21      A1

\n

METHOD 2

\n

finding the standard deviation for their probability distribution found in part (a)    (M1)

\n

Var(T) = (1.101…)2 

\n

= 1.21    A1

\n

Note: Award M1A1 for Var(T) = (1.093…)2 = 1.20.

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.2.AHL.TZ0.6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "ahl-4-14-properties-of-discrete-and-continuous-random-variables" ] }, { "Question": "
\n

Two ships, A and B , are observed from an origin O. Relative to O, their position vectors at time t hours after midday are given by

\n

rA ( 4 3 ) + t ( 5 8 )

\n

rB =  ( 7 3 ) + t ( 0 12 )

\n

where distances are measured in kilometres.

\n

Find the minimum distance between the two ships.

\n
", "Markscheme": "
\n

attempting to find rB − rA for example     (M1)

\n

rB − rA =  ( 3 6 ) + t ( 5 4 )  

\n

attempting to find |rB − rA|     M1

\n

distance d ( t ) = ( 3 5 t ) 2 + ( 4 t 6 ) 2 ( = 41 t 2 78 t + 45 )       A1

\n

using a graph to find the  d  − coordinate of the local minimum      M1

\n

the minimum distance between the ships is 2.81 (km)  ( = 11 41 41 ( km ) )       A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.2.AHL.TZ0.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

A metal sphere has a radius 12.7 cm.

\n
\n

Find the volume of the sphere expressing your answer in the form \na\n×\n\n\n10\nk\n\n\n, \n1\n\na\n<\n10\n and \nk\n\n\nZ\n\n.

\n
[3]
\n
a.
\n
\n

The sphere is to be melted down and remoulded into the shape of a cone with a height of 14.8 cm.

\n

Find the radius of the base of the cone, correct to 2 significant figures.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

\n\n4\n3\n\nπ\n\n\n\n(\n\n12.7\n\n)\n\n3\n\n\n (or equivalent)      A1

\n

8580.24      (A1)

\n

V = 8.58 × 103      A1

\n

[3 marks]

\n
a.
\n
\n

recognising volume of the cone is same as volume of their sphere        (M1)

\n

\n\n1\n3\n\nπ\n\n\nr\n2\n\n\n\n\n(\n\n14.8\n\n)\n\n=\n 8580.24 (or equivalent)      A1

\n

r = 23.529

\n

r = 24 (cm) correct to 2 significant figures       A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.2.SL.TZ0.1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

The complex numbers \nw\n and \nz\n satisfy the equations

\n

\n\nw\nz\n\n=\n2\n\ni\n\n

\n

\n\n\n\nz\n\n\n\n\n\n3\nw\n=\n5\n+\n5\n\ni\n\n.

\n

Find \nw\n and \nz\n in the form \na\n+\nb\n\ni\n\n where \na\n\n\nb\n\n\n\nZ\n\n.

\n
", "Markscheme": "
\n

substituting \nw\n=\n2\n\ni\n\nz\n into \n\n\n\nz\n\n\n\n\n\n3\nw\n=\n5\n+\n5\n\ni\n\n     M1

\n

\n\n\n\nz\n\n\n\n\n\n6\n\ni\n\nz\n=\n5\n+\n5\n\ni\n\n      A1

\n

let \nz\n=\nx\n+\ny\n\ni\n\n

\n

comparing real and imaginary parts of \n\n(\n\nx\n\ny\n\ni\n\n\n)\n\n\n6\n\ni\n\n\n(\n\nx\n+\ny\n\ni\n\n\n)\n\n=\n5\n+\n5\n\ni\n\n     M1

\n

to obtain \nx\n+\n6\ny\n=\n5\n and \n\n6\nx\n\ny\n=\n5\n      A1

\n

attempting to solve for \nx\n and \ny\n)     M1

\n

\nx\n=\n\n1\n and \ny\n=\n1\n so \nz\n=\n\n1\n+\n\ni\n\n      A1

\n

hence \nw\n=\n\n2\n\n2\n\ni\n\n      A1

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.2.AHL.TZ0.8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

Consider the graphs of \ny\n=\n\n\n\n\nx\n2\n\n\n\n\nx\n\n3\n\n\n and \ny\n=\nm\n\n(\n\nx\n+\n3\n\n)\n\n\nm\n\n\nR\n\n.

\n

Find the set of values for \nm\n such that the two graphs have no intersection points.

\n
", "Markscheme": "
\n

METHOD 1

\n

sketching the graph of \ny\n=\n\n\n\n\nx\n2\n\n\n\n\nx\n\n3\n\n\n (\ny\n=\nx\n+\n3\n+\n\n9\n\nx\n\n3\n\n\n)      M1

\n

the (oblique) asymptote has a gradient equal to 1 

\n

and so the maximum value of \nm\n is 1      R1

\n

consideration of a straight line steeper than the horizontal line joining (−3, 0) and (0, 0)      M1

\n

so \nm\n > 0      R1

\n

hence 0 < \nm\n ≤ 1      A1

\n

 

\n

METHOD 2

\n

attempting to eliminate \ny\n to form a quadratic equation in \nx\n       M1 

\n

\n\n\nx\n2\n\n\n=\nm\n\n(\n\n\n\nx\n2\n\n\n\n9\n\n)\n\n

\n

\n\n\n(\n\nm\n\n1\n\n)\n\n\n\nx\n2\n\n\n\n9\nm\n=\n0\n      A1

\n

 

\n

EITHER

\n

attempting to solve \n\n4\n\n(\n\nm\n\n1\n\n)\n\n\n(\n\n\n9\nm\n\n)\n\n<\n0\n for \nm\n       M1 

\n

 

\n

OR

\n

attempting to solve \n\n\nx\n2\n\n\n < 0 ie \n\n\n9\nm\n\n\nm\n\n1\n\n\n<\n0\n\n\n(\n\nm\n\n1\n\n)\n\n for \nm\n       M1

\n

 

\n

THEN

\n

\n\n0\n<\nm\n<\n1\n      A1

\n

a valid reason to explain why \nm\n=\n1\n gives no solutions eg if \nm\n=\n1\n,

\n

\n\n(\n\nm\n\n1\n\n)\n\n\n\nx\n2\n\n\n\n9\nm\n=\n0\n\n\n9\n=\n0\n and so 0 < \nm\n ≤ 1      R1

\n

 

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.2.AHL.TZ0.9", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-13-rational-functions" ] }, { "Question": "
\n

The following diagram shows part of a circle with centre O and radius 4 cm.

\n

\n

Chord AB has a length of 5 cm and AÔB = θ.

\n
\n

Find the value of θ, giving your answer in radians.

\n
[3]
\n
a.
\n
\n

Find the area of the shaded region.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

attempt to use the cosine rule         (M1)

\n

cos θ\n\n\n\n\n4\n2\n\n\n+\n\n\n4\n2\n\n\n\n\n\n5\n2\n\n\n\n\n2\n×\n4\n×\n4\n\n\n (or equivalent)     A1

\n

θ = 1.35      A1

\n

 

\n

METHOD 2

\n

attempt to split triangle AOB into two congruent right triangles      (M1)

\n

sin\n\n(\n\n\nθ\n2\n\n\n)\n\n=\n\n\n2.5\n\n4\n\n      A1

\n

θ = 1.35      A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to find the area of the shaded region      (M1)

\n

\n\n1\n2\n\n×\n4\n×\n4\n×\n\n(\n\n2\nπ\n\n1.35\n\n\n)\n\n      A1

\n

= 39.5 (cm2)      A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.2.SL.TZ0.2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

A large tank initially contains pure water. Water containing salt begins to flow into the tank The solution is kept uniform by stirring and leaves the tank through an outlet at its base. Let \nx\n grams represent the amount of salt in the tank and let \nt\n minutes represent the time since the salt water began flowing into the tank.

\n

The rate of change of the amount of salt in the tank, \n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n, is described by the differential equation \n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n=\n10\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n\nx\n\nt\n+\n1\n\n\n.

\n
\n

Show that \nt\n + 1 is an integrating factor for this differential equation.

\n
[2]
\n
a.
\n
\n

Hence, by solving this differential equation, show that \nx\n\n(\nt\n)\n\n=\n\n\n200\n\n40\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n(\n\nt\n+\n5\n\n)\n\n\n\nt\n+\n1\n\n\n.

\n
[8]
\n
b.
\n
\n

Sketch the graph of \nx\n versus \nt\n for 0 ≤ \nt\n ≤ 60 and hence find the maximum amount of salt in the tank and the value of \nt\n at which this occurs.

\n
[5]
\n
c.
\n
\n

Find the value of \nt\n at which the amount of salt in the tank is decreasing most rapidly.

\n
[2]
\n
d.
\n
\n

The rate of change of the amount of salt leaving the tank is equal to \n\nx\n\nt\n+\n1\n\n\n.

\n

Find the amount of salt that left the tank during the first 60 minutes.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

METHOD 1

\n

\nI\n(\nt\n)\n=\n\n\n\ne\n\n\n\n\nP\n\n(\nt\n)\n\n\n\n\nd\n\nt\n\n\n\n      M1

\n

\n\n\n\ne\n\n\n\n\n\n1\n\nt\n+\n1\n\n\n\n\n\nd\n\nt\n\n\n\n

\n

= \n\n\n\ne\n\n\n\nln\n\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\n       A1

\n

\n=\nt\n+\n1\n       AG

\n

 

\n

METHOD 2

\n

attempting product rule differentiation on \n\n\nd\n\n\n\nd\n\nt\n\n\n\n(\n\nx\n\n(\n\nt\n+\n1\n\n)\n\n\n)\n\n      M1

\n

\n\n\nd\n\n\n\nd\n\nt\n\n\n\n(\n\nx\n\n(\n\nt\n+\n1\n\n)\n\n\n)\n\n=\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n\n(\n\nt\n+\n1\n\n)\n\n+\nx\n

\n

\n=\n\n(\n\nt\n+\n1\n\n)\n\n\n(\n\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n+\n\nx\n\nt\n+\n1\n\n\n\n)\n\n       A1

\n

so \nt\n+\n1\n is an integrating factor for this differential equation        AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

 

\n

attempting to multiply through by \n\n(\n\nt\n+\n1\n\n)\n\n and rearrange to give      (M1)

\n

\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n+\nx\n=\n10\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n         A1

\n

\n\n\nd\n\n\n\nd\n\nt\n\n\n\n(\n\nx\n\n(\n\nt\n+\n1\n\n)\n\n\n)\n\n=\n10\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n

\n

\nx\n\n(\n\nt\n+\n1\n\n)\n\n=\n\n\n10\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n\nd\n\nt\n        A1

\n

attempting to integrate the RHS by parts         M1

\n

\n=\n\n40\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n+\n40\n\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n\n\nd\n\nt\n

\n

\n=\n\n40\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n160\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n+\nC\n         A1

\n

Note: Condone the absence of C.

\n

 

\n

EITHER

\n

substituting \nt\n=\n0\n,\n\n\nx\n=\n0\n\nC\n=\n200\n            M1

\n

\nx\n=\n\n\n\n40\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n160\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n+\n200\n\n\nt\n+\n1\n\n\n        A1

\n

using \n\n40\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n as the highest common factor of \n\n40\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n and \n\n160\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n            M1

\n

 

\n

OR

\n

using \n\n40\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n as the highest common factor of \n\n40\n\n(\n\nt\n+\n1\n\n)\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n and \n\n160\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n giving

\n

\nx\n\n(\n\nt\n+\n1\n\n)\n\n=\n\n40\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n(\n\nt\n+\n5\n\n)\n\n+\nC\n (or equivalent)              M1A1

\n

substituting \nt\n=\n0\n,\n\n\nx\n=\n0\n\nC\n=\n200\n            M1

\n

 

\n

THEN

\n

\nx\n\n(\nt\n)\n\n=\n\n\n200\n\n40\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n(\n\nt\n+\n5\n\n)\n\n\n\nt\n+\n1\n\n\n        AG

\n

 

\n

[8 marks]

\n
b.
\n
\n

 

\n

\n

graph starts at the origin and has a local maximum (coordinates not required)      A1

\n

sketched for 0 ≤ \nt\n ≤ 60      A1

\n

correct concavity for 0 ≤ \nt\n ≤ 60      A1

\n

maximum amount of salt is 14.6 (grams) at \nt\n = 6.60 (minutes)       A1A1 

\n

[5 marks]

\n
c.
\n
\n

using an appropriate graph or equation (first or second derivative)      M1

\n

amount of salt is decreasing most rapidly at \nt\n = 12.9 (minutes)      A1

\n

[2 marks]

\n
d.
\n
\n

EITHER

\n

attempting to form an integral representing the amount of salt that left the tank     M1

\n

\n\n\n0\n\n60\n\n\n\n\n\nx\n\n(\nt\n)\n\n\n\nt\n+\n1\n\n\n\nd\n\nt\n\n

\n

\n\n\n0\n\n60\n\n\n\n\n\n200\n\n40\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n(\n\nt\n+\n5\n\n)\n\n\n\n\n\n\n\n(\n\nt\n+\n1\n\n)\n\n\n2\n\n\n\n\n\nd\n\nt\n\n    A1

\n

 

\n

OR

\n

attempting to form an integral representing the amount of salt that entered the tank minus the amount of salt in the tank at \nt\n = 60(minutes)

\n

amount of salt that left the tank is \n\n\n0\n\n60\n\n\n\n10\n\n\n\n\ne\n\n\n\n\nt\n4\n\n\n\n\n\n\nd\n\nt\n\nx\n\n(\n\n60\n\n)\n\n    A1

\n

 

\n

THEN

\n

= 36.7 (grams)    A2

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "SPM.2.AHL.TZ0.11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

On 1st January 2020, Laurie invests $P in an account that pays a nominal annual interest rate of 5.5 %, compounded quarterly.

\n

The amount of money in Laurie’s account at the end of each year follows a geometric sequence with common ratio, r.

\n
\n

Find the value of r, giving your answer to four significant figures.

\n
[3]
\n
a.
\n
\n

Laurie makes no further deposits to or withdrawals from the account.

\n

Find the year in which the amount of money in Laurie’s account will become double the amount she invested.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

\n\n\n\n(\n\n1\n+\n\n\n5.5\n\n\n4\n×\n100\n\n\n\n)\n\n4\n\n\n      (M1)(A1)

\n

1.056      A1

\n

[3 marks]

\n
a.
\n
\n

EITHER

\n

\n2\nP\n=\nP\n×\n\n\n\n(\n\n1\n+\n\n\n5.5\n\n\n100\n×\n4\n\n\n\n)\n\n\n4\nn\n\n\n\n  OR \n2\nP\n=\nP\n×\n\n\n\n(\n\n\ntheir\n\n\n\n(\na\n)\n\n\n)\n\nm\n\n\n       (M1)(A1)

\n

Note: Award (M1) for substitution into loan payment formula. Award (A1) for correct substitution.

\n

OR

\n

PV = ±1
FV = \n\n1
I% = 5.5
P/Y = 4
C/Y = 4
n = 50.756…       (M1)(A1)

\n

OR

\n

PV = ±1
FV = \n\n2
I% = 100(their (a) − 1)
P/Y = 1
C/Y = 1        (M1)(A1)

\n

THEN

\n

⇒ 12.7 years

\n

Laurie will have double the amount she invested during 2032      A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.2.SL.TZ0.3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

A six-sided biased die is weighted in such a way that the probability of obtaining a “six” is \n\n7\n\n10\n\n\n.

\n
\n

The die is tossed five times. Find the probability of obtaining at most three “sixes”.

\n
[3]
\n
a.
\n
\n

The die is tossed five times. Find the probability of obtaining the third “six” on the fifth toss.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

recognition of binomial      (M1)

\n

X ~ B(5, 0.7)

\n

attempt to find P (X ≤ 3)       M1

\n

= 0.472 (= 0.47178)        A1

\n

[3 marks]

\n
a.
\n
\n

recognition of 2 sixes in 4 tosses    (M1)

\n

P (3rd six on the 5th toss) \n=\n\n[\n\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n×\n\n\n\n\n(\n\n0.7\n\n)\n\n\n2\n\n\n×\n\n\n\n\n(\n\n0.3\n\n)\n\n\n2\n\n\n\n]\n\n×\n0.7\n\n(\n\n=\n0.2646\n×\n0.7\n\n)\n\n        A1

\n

= 0.185 (= 0.18522)       A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.2.SL.TZ0.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

Show that \n\ncot\n\n\n2\nθ\n=\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n2\n\n\ntan\n\n\nθ\n\n\n.

\n
[1]
\n
a.
\n
\n

Verify that \nx\n=\n\ntan\n\n\nθ\n and \nx\n=\n\n\n\ncot\n\n\nθ\n satisfy the equation \n\n\nx\n2\n\n\n+\n\n(\n\n2\n\n\ncot\n\n\n2\nθ\n\n)\n\nx\n\n1\n=\n0\n.

\n
[7]
\n
b.
\n
\n

Hence, or otherwise, show that the exact value of \n\ntan\n\n\nπ\n\n12\n\n\n=\n2\n\n\n3\n\n.

\n
[5]
\n
c.
\n
\n

Using the results from parts (b) and (c) find the exact value of \n\ntan\n\n\nπ\n\n24\n\n\n\n\ncot\n\n\nπ\n\n24\n\n\n.

\n

Give your answer in the form \na\n+\nb\n\n3\n\n where \na\n\nb\n\n\nZ\n\n.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

stating the relationship between \ncot\n and \ntan\n and stating the identity for \n\ntan\n\n\n2\nθ\n       M1

\n

\n\ncot\n\n\n2\nθ\n=\n\n1\n\n\ntan\n\n\n2\nθ\n\n\n and \n\ntan\n\n\n2\nθ\n=\n\n\n2\n\n\ntan\n\n\nθ\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n

\n

⇒ \n\ncot\n\n\n2\nθ\n=\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n2\n\n\ntan\n\n\nθ\n\n\n     AG

\n

[1 mark]

\n
a.
\n
\n

METHOD 1

\n

attempting to substitute \n\ntan\n\n\nθ\n for \nx\n and using the result from (a)      M1

\n

LHS = \n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n+\n2\n\n\ntan\n\n\nθ\n\n(\n\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n2\n\n\ntan\n\n\nθ\n\n\n\n)\n\n\n1\n      A1

\n

\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n+\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n1\n=\n0\n(= RHS)      A1

\n

so \nx\n=\n\ntan\n\n\nθ\n satisfies the equation      AG

\n

attempting to substitute \n\n\n\ncot\n\n\nθ\n for \nx\n and using the result from (a)       M1

\n

LHS = \n\nco\n\n\n\n\nt\n\n2\n\n\n\nθ\n\n2\n\n\ncot\n\n\nθ\n\n(\n\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n2\n\n\ntan\n\n\nθ\n\n\n\n)\n\n\n1\n      A1

\n

\n=\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n\n\n(\n\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n\n)\n\n\n1\n      A1

\n

\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n\n+\n1\n\n1\n=\n0\n(= RHS)     A1

\n

so \nx\n=\n\n\n\ncot\n\n\nθ\n satisfies the equation      AG

\n

 

\n

METHOD 2

\n

let \nα\n=\n\ntan\n\n\nθ\n and \nβ\n=\n\n\n\ncot\n\n\nθ\n

\n

attempting to find the sum of roots       M1

\n

\nα\n+\nβ\n=\n\ntan\n\n\nθ\n\n\n1\n\n\ntan\n\n\nθ\n\n\n

\n

         \n=\n\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n1\n\n\n\ntan\n\n\nθ\n\n\n     A1

\n

         \n=\n\n2\n\n\ncot\n\n\n2\nθ\n (from part (a))     A1

\n

attempting to find the product of roots         M1

\n

\nα\nβ\n=\n\ntan\n\n\nθ\n×\n\n(\n\n\n\n\ncot\n\n\nθ\n\n)\n\n     A1

\n

= −1     A1

\n

the coefficient of \nx\n and the constant term in the quadratic are \n\n2\n\n\ncot\n\n\n2\nθ\n\n and −1 respectively        R1

\n

hence the two roots are \nα\n=\n\ntan\n\n\nθ\n and \nβ\n=\n\n\n\ncot\n\n\nθ\n       AG

\n

[7 marks]

\n
b.
\n
\n

METHOD 1

\n

\nx\n=\n\ntan\n\n\nπ\n\n12\n\n\n and \nx\n=\n\n\ncot\n\n\nπ\n\n12\n\n\n are roots of \n\n\nx\n2\n\n\n+\n\n(\n\n2\n\n\ncot\n\n\nπ\n\n6\n\n\n\n)\n\nx\n\n1\n=\n0\n        R1

\n

Note: Award R1 if only \nx\n=\n\ntan\n\n\nπ\n\n12\n\n\n is stated as a root of \n\n\nx\n2\n\n\n+\n\n(\n\n2\n\n\ncot\n\n\nπ\n\n6\n\n\n\n)\n\nx\n\n1\n=\n0\n.

\n

\n\n\nx\n2\n\n\n+\n2\n\n3\n\nx\n\n1\n=\n0\n        A1

\n

attempting to solve their quadratic equation         M1

\n

\nx\n=\n\n\n3\n\n±\n2\n        A1

\n

\n\ntan\n\n\nπ\n\n12\n\n\n>\n0\n  (\n\n\ncot\n\n\nπ\n\n12\n\n\n<\n0\n)        R1

\n

so \n\ntan\n\n\nπ\n\n12\n\n\n=\n2\n\n\n3\n\n      AG

\n

 

\n

METHOD 2

\n

attempting to substitute \nθ\n=\n\nπ\n\n12\n\n\n into the identity for \n\ntan\n\n\n2\nθ\n           M1

\n

\n\ntan\n\n\nπ\n6\n\n=\n\n\n2\n\n\ntan\n\n\nπ\n\n12\n\n\n\n\n1\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nπ\n\n12\n\n\n\n\n

\n

\n\nta\n\n\n\n\nn\n\n2\n\n\n\nπ\n\n12\n\n\n+\n2\n\n3\n\n\n\ntan\n\n\nπ\n\n12\n\n\n\n1\n=\n0\n     A1

\n

attempting to solve their quadratic equation      M1

\n

\n\ntan\n\n\nπ\n\n12\n\n\n=\n\n\n3\n\n±\n2\n     A1

\n

\n\ntan\n\n\nπ\n\n12\n\n\n>\n0\n      R1

\n

so \n\ntan\n\n\nπ\n\n12\n\n\n=\n2\n\n\n3\n\n      AG

\n

[5 marks]

\n
c.
\n
\n

\n\ntan\n\n\nπ\n\n24\n\n\n\n\ncot\n\n\nπ\n\n24\n\n\n is the sum of the roots of \n\n\nx\n2\n\n\n+\n\n(\n\n2\n\n\ncot\n\n\nπ\n\n12\n\n\n\n)\n\nx\n\n1\n=\n0\n        R1

\n

\n\ntan\n\n\nπ\n\n24\n\n\n\n\ncot\n\n\nπ\n\n24\n\n\n=\n\n2\n\n\ncot\n\n\nπ\n\n12\n\n\n      A1

\n

\n=\n\n\n\n2\n\n\n2\n\n\n3\n\n\n\n      A1

\n

attempting to rationalise their denominator       (M1)

\n

\n=\n\n4\n\n2\n\n3\n\n       A1A1

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "SPM.2.AHL.TZ0.12", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

The following table below shows the marks scored by seven students on two different mathematics tests.

\n

\n

Let L1 be the regression line of x on y. The equation of the line L1 can be written in the form x = ay + b.

\n
\n

Find the value of a and the value of b.

\n
[2]
\n
a.
\n
\n

Let L2 be the regression line of y on x. The lines L1 and L2 pass through the same point with coordinates (p , q).

\n

Find the value of p and the value of q.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

a = 1.29 and b = −10.4      A1A1

\n

[2 marks]

\n
a.
\n
\n

recognising both lines pass through the mean point       (M1)

\n

p = 28.7, q = 30.3       A2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.2.SL.TZ0.5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Consider the expression \nf\n\n(\nx\n)\n\n=\n\ntan\n\n\n(\n\nx\n+\n\nπ\n4\n\n\n)\n\n\ncot\n\n\n(\n\n\nπ\n4\n\n\nx\n\n)\n\n.

\n
\n

The expression \nf\n\n(\nx\n)\n\n can be written as \ng\n\n(\nt\n)\n\n where \nt\n=\n\ntan\n\n\nx\n.

\n
\n

Let \nα\nβ be the roots of \ng\n\n(\nt\n)\n\n=\nk\n, where 0 < \nk\n < 1.

\n
\n

Sketch the graph of  y = f ( x ) for  5 π 8 x π 8 .

\n
[2]
\n
a.i.
\n
\n

With reference to your graph, explain why  f  is a function on the given domain.

\n
[1]
\n
a.ii.
\n
\n

Explain why f has no inverse on the given domain.

\n
[1]
\n
a.iii.
\n
\n

Explain why f is not a function for 3 π 4 x π 4 .

\n
[1]
\n
a.iv.
\n
\n

Show that  g ( t ) = ( 1 + t 1 t ) 2 .

\n
[3]
\n
b.
\n
\n

Sketch the graph of  y = g ( t ) for t ≤ 0. Give the coordinates of any intercepts and the equations of any asymptotes.

\n
[3]
\n
c.
\n
\n

Find  α and β in terms of k .

\n
[5]
\n
d.i.
\n
\n

Show that  α  + β < −2.

\n
[2]
\n
d.ii.
\n
", "Markscheme": "
\n

     A1A1

\n

A1 for correct concavity, many to one graph, symmetrical about the midpoint of the domain and with two axes intercepts.

\n

Note: Axes intercepts and scales not required.

\n

A1 for correct domain

\n

[2 marks]

\n
a.i.
\n
\n

for each value of x there is a unique value of f ( x )       A1

\n

Note: Accept “passes the vertical line test” or equivalent.

\n

[1 mark]

\n
a.ii.
\n
\n

no inverse because the function fails the horizontal line test or equivalent      R1

\n

Note: No FT if the graph is in degrees (one-to-one).

\n

[1 mark]

\n
a.iii.
\n
\n

the expression is not valid at either of x = π 4 ( or 3 π 4 )        R1

\n

[1 mark]

\n
a.iv.
\n
\n

METHOD 1

\n

f ( x ) = tan ( x + π 4 ) tan ( π 4 x )      M1

\n

= tan x + tan π 4 1 tan x tan π 4 tan π 4 tan x 1 + tan π 4 tan x       M1A1

\n

= ( 1 + t 1 t ) 2       AG

\n

 

\n

METHOD 2

\n

f ( x ) = tan ( x + π 4 ) tan ( π 2 π 4 + x )       (M1)

\n

= ta n 2 ( x + π 4 )      A1

\n

g ( t ) = ( tan x + tan π 4 1 tan x tan π 4 ) 2      A1

\n

= ( 1 + t 1 t ) 2       AG

\n

[3 marks]

\n
b.
\n
\n

 

\n

\n

for t ≤ 0, correct concavity with two axes intercepts and with asymptote y  = 1      A1

\n

t intercept at (−1, 0)      A1

\n

y intercept at (0, 1)       A1

\n

[3 marks]

\n
c.
\n
\n

METHOD 1

\n

α β satisfy ( 1 + t ) 2 ( 1 t ) 2 = k      M1

\n

1 + t 2 + 2 t = k ( 1 + t 2 2 t )      A1

\n

( k 1 ) t 2 2 ( k + 1 ) t + ( k 1 ) = 0      A1

\n

attempt at using quadratic formula      M1

\n

α β  = k + 1 ± 2 k k 1 or equivalent     A1

\n

 

\n

METHOD 2

\n

α β satisfy  1 + t 1 t = ( ± ) k       M1

\n

t + k t = k 1       M1

\n

t = k 1 k + 1  (or equivalent)      A1

\n

t k t = ( k + 1 )      M1

\n

t = k + 1 k 1  (or equivalent)       A1

\n

so for eg α = k 1 k + 1 β = k + 1 k 1

\n

[5 marks]

\n
d.i.
\n
\n

α  + β  = 2 ( k + 1 ) ( k 1 ) ( = 2 ( 1 + k ) ( 1 k ) )      A1

\n

since  1 + k > 1 k      R1

\n

α  + β < −2     AG

\n

Note: Accept a valid graphical reasoning.

\n

[2 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
a.iv.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "18M.2.AHL.TZ2.H_10", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-6-quadratic-function", "sl-2-3-graphing" ] }, { "Question": "
\n

The displacement, in centimetres, of a particle from an origin, O, at time t seconds, is given by s(t) = t 2 cos t + 2t sin t, 0 ≤ t ≤ 5.

\n
\n

Find the maximum distance of the particle from O.

\n
[3]
\n
a.
\n
\n

Find the acceleration of the particle at the instant it first changes direction.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

use of a graph to find the coordinates of the local minimum      (M1)

\n

s = −16.513...      (A1)

\n

maximum distance is 16.5 cm (to the left of O)      A1

\n

[3 marks]

\n
a.
\n
\n

attempt to find time when particle changes direction eg considering the first maximum on the graph of s or the first t – intercept on the graph of s'.        (M1)

\n

t = 1.51986...        (A1)

\n

attempt to find the gradient of s' for their value of t, s\" (1.51986...)       (M1)

\n

=–8.92(cm/s2)       A1

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.2.SL.TZ0.6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

Find the acute angle between the planes with equations x + y + z = 3 and 2 x z = 2 .

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

n 1 = ( 1 1 1 ) and n 2 = ( 2 0 1 )      (A1)(A1)

\n

EITHER

\n

θ = arccos ( n 1 n 2 | n 1 | | n 2 | ) ( cos θ = n 1 n 2 | n 1 | | n 2 | )    (M1)

\n

= arccos ( 2 + 0 1 3 5 ) ( cos θ = 2 + 0 1 3 5 )    (A1)

\n

= arccos ( 1 15 ) ( cos θ = 1 15 )

\n

OR

\n

θ = arcsin ( | n 1 × n 2 | | n 1 | | n 2 | ) ( sin θ = | n 1 × n 2 | | n 1 | | n 2 | )    (M1)

\n

= arcsin ( 14 3 5 ) ( sin θ = 14 3 5 )    (A1)

\n

= arcsin ( 14 15 ) ( sin θ = 14 15 )

\n

 

\n

THEN

\n

= 75.0  (or 1.31)    A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.2.AHL.TZ0.H_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-18-intersections-of-lines-&-planes" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\n\n2\n\n\nln\n\n\nx\n+\n1\n\n\nx\n\n3\n\n\n, 0 < \nx\n < 3.

\n
\n

Draw a set of axes showing \nx\n and \ny\n values between −3 and 3. On these axes

\n
\n

Hence, or otherwise, find the coordinates of the point of inflexion on the graph of  y = f ( x ) .

\n
[4]
\n
b.
\n
\n

sketch the graph of y = f ( x ) , showing clearly any axis intercepts and giving the equations of any asymptotes.

\n
[4]
\n
c.i.
\n
\n

sketch the graph of y = f 1 ( x ) , showing clearly any axis intercepts and giving the equations of any asymptotes.

\n
[4]
\n
c.ii.
\n
\n

Hence, or otherwise, solve the inequality f ( x ) > f 1 ( x ) .

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

finding turning point of  y = f ( x ) or finding root of y = f ( x )        (M1)

\n

x = 0.899        A1

\n

y = f ( 0.899048 ) = 0.375       (M1)A1

\n

(0.899, −0.375)

\n

Note: Do not accept x = 0.9 . Accept y-coordinates rounding to −0.37 or −0.375 but not −0.38.
 

\n

[4 marks]

\n
b.
\n
\n

\n

smooth curve over the correct domain which does not cross the y-axis

\n

and is concave down for x  > 1       A1

\n

x -intercept at 0.607       A1

\n

equations of asymptotes given as x  = 0 and x  = 3 (the latter must be drawn)       A1A1
 

\n

[4 marks]

\n
c.i.
\n
\n

\n

attempt to reflect graph of f in y  = x        (M1)

\n

smooth curve over the correct domain which does not cross the x -axis and is concave down for y  > 1       A1

\n

y -intercept at 0.607       A1

\n

equations of asymptotes given as y  = 0 and y  = 3 (the latter must be drawn)       A1

\n

Note: For FT from (i) to (ii) award max M1A0A1A0.

\n


[4 marks]

\n
c.ii.
\n
\n

solve  f ( x ) = f 1 ( x ) or  f ( x ) = x to get x  = 0.372        (M1)A1

\n

0 <  x < 0.372      A1

\n

Note: Do not award FT marks.

\n


[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "18N.2.AHL.TZ0.H_9", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

This question asks you to investigate regular \nn\n-sided polygons inscribed and circumscribed in a circle, and the perimeter of these as \nn\n tends to infinity, to make an approximation for \nπ\n.

\n
\n

Let \n\n\nP\ni\n\n\n\n(\nn\n)\n\n represent the perimeter of any \nn\n-sided regular polygon inscribed in a circle of radius 1 unit.

\n
\n

Consider an equilateral triangle ABC of side length, \nx\n units, circumscribed about a circle of radius 1 unit and centre O as shown in the following diagram.

\n

\n

Let \n\n\nP\nc\n\n\n\n(\nn\n)\n\n represent the perimeter of any \nn\n-sided regular polygon circumscribed about a circle of radius 1 unit.

\n
\n

Consider an equilateral triangle ABC of side length, x units, inscribed in a circle of radius 1 unit and centre O as shown in the following diagram.

\n

\n

The equilateral triangle ABC can be divided into three smaller isosceles triangles, each subtending an angle of  2 π 3  at O, as shown in the following diagram.

\n

\n

Using right-angled trigonometry or otherwise, show that the perimeter of the equilateral triangle ABC is equal to  3 3 units.

\n
[3]
\n
a.
\n
\n

Consider a square of side length, x units, inscribed in a circle of radius 1 unit. By dividing the inscribed square into four isosceles triangles, find the exact perimeter of the inscribed square.

\n

 

\n
[3]
\n
b.
\n
\n

Find the perimeter of a regular hexagon, of side length, x units, inscribed in a circle of radius 1 unit.

\n

 

\n
[2]
\n
c.
\n
\n

Show that  P i ( n ) = 2 n sin ( π n ) .

\n
[3]
\n
d.
\n
\n

Use an appropriate Maclaurin series expansion to find  lim n P i ( n ) and interpret this result geometrically.

\n
[5]
\n
e.
\n
\n

Show that  P c ( n ) = 2 n tan ( π n ) .

\n
[4]
\n
f.
\n
\n

By writing  P c ( n )  in the form  2 tan ( π n ) 1 n , find  lim n P c ( n ) .

\n
[5]
\n
g.
\n
\n

Use the results from part (d) and part (f) to determine an inequality for the value of π in terms of n .

\n
[2]
\n
h.
\n
\n

The inequality found in part (h) can be used to determine lower and upper bound approximations for the value of π .

\n

Determine the least value for n such that the lower bound and upper bound approximations are both within 0.005 of π .

\n
[3]
\n
i.
\n
", "Markscheme": "
\n

METHOD 1

\n

consider right-angled triangle OCX where CX  = x 2

\n

sin π 3 = x 2 1        M1A1

\n

x 2 = 3 2 x = 3       A1

\n

P i = 3 × x = 3 3       AG

\n

 

\n

METHOD 2

\n

eg  use of the cosine rule  x 2 = 1 2 + 1 2 2 ( 1 ) ( 1 ) cos 2 π 3           M1A1    

\n

x = 3       A1

\n

P i = 3 × x = 3 3       AG

\n

Note: Accept use of sine rule.

\n

 

\n

[3 marks]

\n
a.
\n
\n

sin π 4 = 1 x where x  = side of square      M1

\n

x = 2        A1

\n

P i = 4 2        A1

\n

[3 marks]

\n
b.
\n
\n

6 equilateral triangles ⇒ x = 1       A1

\n

P i = 6       A1

\n

[2 marks]

\n
c.
\n
\n

in right-angled triangle  sin ( π n ) = x 2 1      M1

\n

x = 2 sin ( π n )      A1

\n

P i = n × x

\n

P i = n × 2 sin ( π n )      M1

\n

P i = 2 n sin ( π n )      AG

\n

[3 marks]

\n
d.
\n
\n

consider  lim n 2 n sin ( π n )

\n

use of  sin x = x x 3 3 ! + x 5 5 !       M1

\n

2 n sin ( π n ) = 2 n ( π n π 3 6 n 3 + π 5 120 n 5 )       (A1)

\n

= 2 ( π π 3 6 n 2 + π 5 120 n 4 )       A1

\n

lim n 2 n sin ( π n ) = 2 π      A1

\n

as  n polygon becomes a circle of radius 1 and  P i = 2 π      R1

\n

[5 marks]

\n
e.
\n
\n

consider an n -sided polygon of side length x

\n

2 n right-angled triangles with angle  2 π 2 n = π n  at centre       M1A1

\n

opposite side  x 2 = tan ( π n ) x = 2 tan ( π n )        M1A1

\n

Perimeter  P c = 2 n tan ( π n )        AG

\n

[4 marks]

\n
f.
\n
\n

consider  lim n 2 n tan ( π n ) = lim n ( 2 tan ( π n ) 1 n )

\n

= lim n ( 2 tan ( π n ) 1 n ) = 0 0          R1

\n

attempt to use L’Hopital’s rule        M1

\n

= lim n ( 2 π n 2 se c 2 ( π n ) 1 n 2 )        A1A1

\n

= 2 π        A1

\n

[5 marks]

\n
g.
\n
\n

P i < 2 π < P c

\n

2 n sin ( π n ) < 2 π < 2 n tan ( π n )        M1

\n

n sin ( π n ) < π < n tan ( π n )        A1

\n

[2 marks]

\n
h.
\n
\n

attempt to find the lower bound and upper bound approximations within 0.005 of π     (M1)

\n

n = 46        A2

\n

[3 marks]

\n
i.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
\n[N/A]\n
i.
\n
", "question_id": "SPM.3.AHL.TZ0.1", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\nsec\n\n\nx\n+\n2\n, \n0\n\nx\n<\n\nπ\n2\n\n.

\n
\n

Write down the range of f .

\n
[1]
\n
a.
\n
\n

Find f-1(x), stating its domain.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

f ( x ) ≥ 3      A1

\n

[1 mark]

\n
a.
\n
\n

x = sec y + 2        (M1)

\n

Note: Exchange of variables can take place at any point.

\n

cos y = 1 x 2        (A1)

\n

f ( x ) = arccos ( 1 x 2 ) , x  ≥ 3      A1A1

\n

Note: Allow follow through from (a) for last A1 mark which is independent of earlier marks in (b).

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.AHL.TZ1.H_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

The following scatter diagram shows the scores obtained by seven students in their mathematics test, m, and their physics test, p.

\n

\n

The mean point, M, for these data is (40, 16).

\n
\n

Plot and label the point M\n\n(\n\n\n\nm\n¯\n\n\n,\n\n\n\n\np\n¯\n\n\n\n)\n\n on the scatter diagram.

\n
[2]
\n
a.
\n
\n

Draw the line of best fit, by eye, on the scatter diagram.

\n
[2]
\n
b.
\n
\n

Using your line of best fit, estimate the physics test score for a student with a score of 20 in their mathematics test.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(A1)(A1) (C2)

\n

Note: Award (A1) for mean point plotted and (A1) for labelled M.

\n

[2 marks]

\n
a.
\n
\n

straight line through their mean point crossing the p-axis at 5±2     (A1)(ft)(A1)(ft) (C2)

\n

Note: Award (A1)(ft) for a straight line through their mean point. Award (A1)(ft) for a correct p-intercept if line is extended.

\n

[2 marks]

\n
b.
\n
\n

point on line where m = 20 identified and an attempt to identify y-coordinate     (M1)

\n

10.5     (A1)(ft)    (C2)

\n

Note: Follow through from their line in part (b).

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ2.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A healthy human body temperature is 37.0 °C. Eight people were medically examined and the difference in their body temperature (°C), from 37.0 °C, was recorded. Their heartbeat (beats per minute) was also recorded.

\n

\n
\n

Draw a scatter diagram for temperature difference from 37 °C (\nx\n) against heartbeat (\ny\n). Use a scale of 2 cm for 0.1 °C on the horizontal axis, starting with −0.3 °C. Use a scale of 1 cm for 2 heartbeats per minute on the vertical axis, starting with 60 beats per minute.

\n
[4]
\n
a.
\n
\n

Write down, for this set of data the mean temperature difference from 37 °C, \n\n\nx\n¯\n\n\n.

\n
[1]
\n
b.i.
\n
\n

Write down, for this set of data the mean number of heartbeats per minute, \n\n\ny\n¯\n\n\n.

\n
[1]
\n
b.ii.
\n
\n

Plot and label the point M(\n\n\nx\n¯\n\n\n, \n\n\ny\n¯\n\n\n) on the scatter diagram.

\n
[2]
\n
c.
\n
\n

Use your graphic display calculator to find the Pearson’s product–moment correlation coefficient, \nr\n.

\n
[2]
\n
d.i.
\n
\n

Hence describe the correlation between temperature difference from 37 °C and heartbeat.

\n
[2]
\n
d.ii.
\n
\n

Use your graphic display calculator to find the equation of the regression line \ny\n on \nx\n.

\n
[2]
\n
e.
\n
\n

Draw the regression line \ny\n on \nx\n on the scatter diagram.

\n
[2]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

  (A4)

\n

Note: Award (A1) for correct scales, axis labels, minimum \nx\n=\n\n0.3\n, and minimum \ny\n=\n60\n. Award (A0) if axes are reversed and follow through for their points.

\n

Award    (A3) for all eight points correctly plotted,
              (A2) for six or seven points correctly plotted.
              (A1) for four or five points correctly plotted.

\n

Allow a tolerance of half a small square.

\n

If graph paper has not been used, award at most (A1)(A0)(A0)(A0).

\n

If accuracy cannot be determined award (A0)(A0)(A0)(A0).

\n

[4 marks]

\n
a.
\n
\n

0.025 \n\n(\n\n\n1\n\n40\n\n\n\n)\n\n    (A1)

\n

[1 mark]

\n
b.i.
\n
\n

74        (A1)

\n

[1 mark]

\n
b.ii.
\n
\n

the point M labelled, correctly plotted on their diagram        (A1)(A1)(ft)

\n

Note: Award (A1) for labelled M. Do not accept any other label. Award (A1)(ft) for their point M correctly plotted. Follow through from part (b).

\n

[2 marks]

\n
c.
\n
\n

0.807 (0.806797…)       (G2)

\n

[2 marks]

\n
d.i.
\n
\n

(moderately) strong, positive       (A1)(ft)(A1)(ft)

\n

Note: Award (A1) for (moderately) strong, (A1) for positive. Follow through from part (d)(i). If there is no answer to part (d)(i), award at most (A0)(A1).

\n

[2 marks]

\n
d.ii.
\n
\n

\ny\n=\n22.0\nx\n+\n73.5\n\n\n\n(\n\ny\n=\n21.9819\n\nx\n+\n73.4504\n\n\n)\n\n      (G2)

\n

Note: Award (G1) for \n22.0\nx\n, (G1) for 73.5.

\n

Award a maximum of (G0)(G1) if the answer is not an equation.

\n

[2 marks]

\n
e.
\n
\n

their regression line correctly drawn on scatter diagram (A1)(ft)(A1)(ft)

\n

Note: Award (A1)(ft) for a straight line, using a ruler, intercepting their mean point, and (A1)(ft) for intercepting the \ny\n-axis at their 73.5 and the gradient of the line is positive. If graph paper is not used, award at most (A1)(A0). Follow through from part (e).

\n

[2 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "19M.2.SL.TZ1.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Sketch the graph of  y = x 4 2 x 5 , stating the equations of any asymptotes and the coordinates of any points of intersection with the axes.

\n

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

\n

correct shape: two branches in correct quadrants with asymptotic behaviour      A1

\n

crosses at (4, 0) and  ( 0 , 4 5 )       A1A1

\n

asymptotes at  x = 5 2 and  y = 1 2       A1A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ2.H_5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-8-reciprocal-and-simple-rational-functions-equations-of-asymptotes" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n(\nx\n)\n=\n2\n\n\nx\n3\n\n\n+\n5\n,\n\n \n\n\n2\n\nx\n\n2\n.

\n
\n

Write down the range of \nf\n.

\n
[2]
\n
a.
\n
\n

Find an expression for \n\n\nf\n\n\n1\n\n\n\n(\nx\n)\n.

\n
[2]
\n
b.
\n
\n

Write down the domain and range of \n\n\nf\n\n\n1\n\n\n\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n11\n\nf\n(\nx\n)\n\n21\n     A1A1

\n

 

\n

Note:     A1 for correct end points, A1 for correct inequalities.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n\n\nf\n\n\n1\n\n\n\n(\nx\n)\n=\n\n\n\n\nx\n\n5\n\n2\n\n\n3\n\n     (M1)A1

\n

[2 marks]

\n
b.
\n
\n

\n\n11\n\nx\n\n21\n,\n\n \n\n\n2\n\n\n\nf\n\n\n1\n\n\n\n(\nx\n)\n\n2\n     A1A1

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.AHL.TZ2.H_2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Sketch the graph of y = 1 3 x x 2 , showing clearly any asymptotes and stating the coordinates of any points of intersection with the axes.

\n

\"N17/5/MATHL/HP1/ENG/TZ0/06.a\"

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

\"N17/5/MATHL/HP1/ENG/TZ0/06.a/M\"

\n

correct vertical asymptote     A1

\n

shape including correct horizontal asymptote     A1

\n

( 1 3 ,   0 )     A1

\n

( 0 ,   1 2 )     A1

\n

 

\n

Note:     Accept x = 1 3 and y = 1 2 marked on the axes.

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.AHL.TZ0.H_6", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing" ] }, { "Question": "
\n

Consider the function \nf\n(\nx\n)\n=\n\n\n\nx\n\n\n\nsin\n\nx\n\n\n,\n\n \n\n0\n<\nx\n<\nπ\n.

\n
\n

Consider the region bounded by the curve \ny\n=\nf\n(\nx\n)\n, the \nx\n-axis and the lines \nx\n=\n\nπ\n6\n\n,\n\n \n\nx\n=\n\nπ\n3\n\n.

\n
\n

Show that the x -coordinate of the minimum point on the curve y = f ( x ) satisfies the equation tan x = 2 x .

\n
[5]
\n
a.i.
\n
\n

Determine the values of x for which f ( x ) is a decreasing function.

\n
[2]
\n
a.ii.
\n
\n

Sketch the graph of y = f ( x ) showing clearly the minimum point and any asymptotic behaviour.

\n
[3]
\n
b.
\n
\n

Find the coordinates of the point on the graph of f where the normal to the graph is parallel to the line y = x .

\n
[4]
\n
c.
\n
\n

This region is now rotated through 2 π radians about the x -axis. Find the volume of revolution.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

attempt to use quotient rule or product rule     M1

\n

f ( x ) = sin x ( 1 2 x 1 2 ) x cos x sin 2 x   ( = 1 2 x sin x x cos x sin 2 x )     A1A1

\n

 

\n

Note:     Award A1 for 1 2 x sin x or equivalent and A1 for x cos x sin 2 x or equivalent.

\n

 

\n

setting f ( x ) = 0     M1

\n

sin x 2 x x cos x = 0

\n

sin x 2 x = x cos x or equivalent     A1

\n

tan x = 2 x     AG

\n

[5 marks]

\n
a.i.
\n
\n

x = 1.17

\n

0 < x 1.17     A1A1

\n

 

\n

Note:     Award A1 for 0 < x and A1 for x 1.17 . Accept x < 1.17 .

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

\"N17/5/MATHL/HP2/ENG/TZ0/10.b/M\"

\n

concave up curve over correct domain with one minimum point above the x -axis.     A1

\n

approaches x = 0 asymptotically     A1

\n

approaches x = π asymptotically     A1

\n

 

\n

Note:     For the final A1 an asymptote must be seen, and π must be seen on the x -axis or in an equation.

\n

 

\n

[3 marks]

\n
b.
\n
\n

f ( x )   ( = sin x ( 1 2 x 1 2 ) x cos x sin 2 x ) = 1     (A1)

\n

attempt to solve for x     (M1)

\n

x = 1.96     A1

\n

y = f ( 1.96 )

\n

= 1.51     A1

\n

[4 marks]

\n
c.
\n
\n

V = π π 6 π 3 x d x sin 2 x     (M1)(A1)

\n

 

\n

Note:     M1 is for an integral of the correct squared function (with or without limits and/or π ).

\n

 

\n

= 2.68   ( = 0.852 π )     A1

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17N.2.AHL.TZ0.H_10", "topics": [ "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion", "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Colorado beetles are a pest, which can cause major damage to potato crops. For a certain Colorado beetle the amount of oxygen, in millilitres (ml), consumed each day increases with temperature as shown in the following table.

\n

\n

This information has been used to plot a scatter diagram.

\n

\n
\n

The mean point has coordinates (20, 230).

\n
\n

Find the equation of the regression line of \ny\n on \nx\n.

\n
[2]
\n
a.
\n
\n

Draw the regression line of \ny\n on \nx\n on the scatter diagram.

\n
[2]
\n
b.
\n
\n

In order to estimate the amount of oxygen consumed, this regression line is considered to be reliable for a temperature \nx\n such that \na\n\nx\n\nb\n.

\n

Write down the value of \na\n and of \nb\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ny\n=\n15.5\nx\n\n80\n    (A1)(A1)  (C2)

\n

Note: Award (A1) for \n15.5\nx\n; (A1) for −80. Award at most (A1)(A0) if answer is not an equation. Award (A0)(A1)(ft) for \ny\n=\n\n80\nx\n+\n15.5\n.

\n

[2 marks]

\n

 

\n
a.
\n
\n

  (A1)(A1)  (C2)

\n

Note: Award (A1) for a straight line using a ruler passing through (20, 230); (A1) for correct \ny\n-intercept. If a ruler has not been used, award at most (A0)(A1).

\n

[2 marks] 

\n
b.
\n
\n

\na\n=\n10\n  AND  \nb\n=\n30\n   (A1)(A1)  (C2)

\n

Note: Accept [10, 30] or 10 ≤ \nx\n ≤ 30.

\n

[2 marks] 

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Consider the function \nf\n(\nx\n)\n=\n\n1\n\n\n\nx\n2\n\n\n+\n3\nx\n+\n2\n\n\n,\n\n \n\nx\n\n\nR\n\n,\n\n \n\nx\n\n\n2\n,\n\n \n\nx\n\n\n1\n.

\n
\n

Express x 2 + 3 x + 2 in the form ( x + h ) 2 + k .

\n
[1]
\n
a.i.
\n
\n

Factorize x 2 + 3 x + 2 .

\n
[1]
\n
a.ii.
\n
\n

Sketch the graph of f ( x ) , indicating on it the equations of the asymptotes, the coordinates of the y -intercept and the local maximum.

\n
[5]
\n
b.
\n
\n

Hence find the value of p if 0 1 f ( x ) d x = ln ( p ) .

\n
[4]
\n
d.
\n
\n

Sketch the graph of y = f ( | x | ) .

\n
[2]
\n
e.
\n
\n

Determine the area of the region enclosed between the graph of y = f ( | x | ) , the x -axis and the lines with equations x = 1 and x = 1 .

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

x 2 + 3 x + 2 = ( x + 3 2 ) 2 1 4      A1

\n

[1 mark]

\n
a.i.
\n
\n

x 2 + 3 x + 2 = ( x + 2 ) ( x + 1 )      A1

\n

[1 mark]

\n
a.ii.
\n
\n

\"M17/5/MATHL/HP1/ENG/TZ1/B11.b/M\"

\n

A1 for the shape

\n

A1 for the equation y = 0

\n

A1 for asymptotes x = 2 and x = 1

\n

A1 for coordinates ( 3 2 ,   4 )

\n

A1 y -intercept ( 0 ,   1 2 )

\n

[5 marks]

\n
b.
\n
\n

0 1 1 x + 1 1 x + 2 d x

\n

= [ ln ( x + 1 ) ln ( x + 2 ) ] 0 1      A1

\n

= ln 2 ln 3 ln 1 + ln 2      M1

\n

= ln ( 4 3 )      M1A1

\n

p = 4 3

\n

[4 marks]

\n
d.
\n
\n

\"M17/5/MATHL/HP1/ENG/TZ1/B11.e/M\"

\n

symmetry about the y -axis     M1

\n

correct shape     A1

\n

 

\n

Note:     Allow FT from part (b).

\n

 

\n

[2 marks]

\n
e.
\n
\n

2 0 1 f ( x ) d x      (M1)(A1)

\n

= 2 ln ( 4 3 )      A1

\n

 

\n

Note:     Do not award FT from part (e).

\n

 

\n

[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "17M.1.AHL.TZ1.H_11", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-6-quadratic-function", "sl-5-11-definite-integrals-areas-under-curve-onto-x-axis-and-areas-between-curves" ] }, { "Question": "
\n

Consider the functions \nf\n\n(\nx\n)\n\n=\n\n\nx\n4\n\n\n\n2\n and \ng\n\n(\nx\n)\n\n=\n\n\nx\n3\n\n\n\n4\n\n\nx\n2\n\n\n+\n2\nx\n+\n6\n

\n

The functions intersect at points P and Q. Part of the graph of \ny\n=\nf\n\n(\nx\n)\n\n and part of the graph of \ny\n=\ng\n\n(\nx\n)\n\n are shown on the diagram.

\n

\n
\n

Find the range of f.

\n
[2]
\n
a.
\n
\n

Write down the x-coordinate of P and the x-coordinate of Q.

\n
[2]
\n
b.
\n
\n

Write down the values of x for which  f ( x ) > g ( x ) .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

[ 2 , [  or  [ 2 , ) OR  f ( x ) 2  or  y 2 OR  2 f ( x ) <      (A1)(A1) (C2)

\n

Note: Award (A1) for −2 and (A1) for completely correct mathematical notation, including weak inequalities. Accept  f 2 .

\n

[2 marks]

\n
a.
\n
\n

–1 and 1.52 (1.51839…)     (A1)(A1) (C2)

\n

Note: Award (A1) for −1 and (A1) for 1.52 (1.51839).

\n

[2 marks]

\n
b.
\n
\n

x < 1 , x > 1.52   OR  ( , 1 ) ( 1.52 , ) .    (A1)(ft)(A1)(ft) (C2)

\n

Note: Award (A1)(ft) for both critical values in inequality or range statements such as  x < 1 , ( , 1 ) , x > 1.52  or  ( 1.52 , ) .

\n

Award the second (A1)(ft) for correct strict inequality statements used with their critical values. If an incorrect use of strict and weak inequalities has already been penalized in (a), condone weak inequalities for this second mark and award (A1)(ft).

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ1.T_15", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Consider the function \nf\n defined by \nf\n(\nx\n)\n=\n\n\nx\n2\n\n\n\n\n\na\n2\n\n\n,\n\n \n\nx\n\n\nR\n\n where \na\n is a positive constant.

\n
\n

The function \ng\n is defined by \ng\n(\nx\n)\n=\nx\n\nf\n(\nx\n)\n\n for \n\n|\nx\n|\n\n>\na\n.

\n
\n

Showing any x and y intercepts, any maximum or minimum points and any asymptotes, sketch the following curves on separate axes.

\n

y = f ( x ) ;

\n
[2]
\n
a.i.
\n
\n

Showing any x and y intercepts, any maximum or minimum points and any asymptotes, sketch the following curves on separate axes.

\n

y = 1 f ( x ) ;

\n
[4]
\n
a.ii.
\n
\n

Showing any x and y intercepts, any maximum or minimum points and any asymptotes, sketch the following curves on separate axes.

\n

y = | 1 f ( x ) | .

\n
[2]
\n
a.iii.
\n
\n

Find f ( x ) cos x d x .

\n
[5]
\n
b.
\n
\n

By finding g ( x ) explain why g is an increasing function.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

\"M17/5/MATHL/HP1/ENG/TZ2/09.a.i/M\"

\n

A1 for correct shape

\n

A1 for correct x and y intercepts and minimum point

\n

[2 marks]

\n
a.i.
\n
\n

\"M17/5/MATHL/HP1/ENG/TZ2/09.a.ii/M\"

\n

A1 for correct shape

\n

A1 for correct vertical asymptotes

\n

A1 for correct implied horizontal asymptote

\n

A1 for correct maximum point

\n

[??? marks]

\n
a.ii.
\n
\n

\"M17/5/MATHL/HP1/ENG/TZ2/09.a.iii/M\"

\n

A1 for reflecting negative branch from (ii) in the x -axis

\n

A1 for correctly labelled minimum point

\n

[2 marks]

\n
a.iii.
\n
\n

EITHER

\n

attempt at integration by parts     (M1)

\n

( x 2 a 2 ) cos x d x = ( x 2 a 2 ) sin x 2 x sin x d x      A1A1

\n

= ( x 2 a 2 ) sin x 2 [ x cos x + cos x d x ]      A1

\n

= ( x 2 a 2 ) sin x + 2 x cos 2 sin x + c      A1

\n

OR

\n

( x 2 a 2 ) cos x d x = x 2 cos x d x a 2 cos x d x

\n

attempt at integration by parts     (M1)

\n

x 2 cos x d x = x 2 sin x 2 x sin x d x      A1A1

\n

= x 2 sin x 2 [ x cos x + cos x d x ]      A1

\n

= x 2 sin x + 2 x cos x 2 sin x

\n

a 2 cos x d x = a 2 sin x

\n

( x 2 a 2 ) cos x d x = ( x 2 a 2 ) sin x + 2 x cos x 2 sin x + c      A1

\n

[5 marks]

\n
b.
\n
\n

g ( x ) = x ( x 2 a 2 ) 1 2

\n

g ( x ) = ( x 2 a 2 ) 1 2 + 1 2 x ( x 2 a 2 ) 1 2 ( 2 x )     M1A1A1

\n

 

\n

Note:     Method mark is for differentiating the product. Award A1 for each correct term.

\n

 

\n

g ( x ) = ( x 2 a 2 ) 1 2 + x 2 ( x 2 a 2 ) 1 2

\n

both parts of the expression are positive hence g ( x ) is positive     R1

\n

and therefore g is an increasing function (for | x | > a )     AG

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.AHL.TZ2.H_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Line \nL\n intersects the \nx\n-axis at point A and the \ny\n-axis at point B, as shown on the diagram.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/04\"

\n

The length of line segment OB is three times the length of line segment OA, where O is the origin.

\n
\n

Point \n\n(2, 6)\n\n lies on \nL\n.

\n
\n

Find the equation of \nL\n in the form \ny\n=\nm\nx\n+\nc\n.

\n
[2]
\n
b.
\n
\n

Find the \nx\n-coordinate of point A.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

\n6\n=\n\n3\n(\n2\n)\n+\nc\n\n\n\n\nOR\n\n\n\n\n(\ny\n\n6\n)\n=\n\n3\n(\nx\n\n2\n)\n     (M1)

\n

 

\n

Note:     Award (M1) for substitution of their gradient from part (a) into a correct equation with the coordinates \n(\n2\n,\n\n \n\n6\n)\n correctly substituted.

\n

\ny\n=\n\n3\nx\n+\n12\n     (A1)(ft)     (C2)

\n

 

\n

Notes:     Award (A1)(ft) for their correct equation. Follow through from part (a).

\n

If no method seen, award (A1)(A0) for \ny\n=\n\n3\nx\n.

\n

Award (A1)(A0) for \n\n3\nx\n+\n12\n.

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n0\n=\n\n3\nx\n+\n12\n     (M1)

\n

 

\n

Note:     Award (M1) for substitution of \ny\n=\n0\n in their equation from part (b).

\n

 

\n

\n(\nx\n=\n)\n\n \n\n4\n     (A1)(ft)     (C2)

\n

 

\n

Notes:     Follow through from their equation from part (b). Do not follow through if no method seen. Do not award the final (A1) if the value of \nx\n is negative or zero.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-1-equations-of-straight-lines-parallel-and-perpendicular" ] }, { "Question": "
\n

Sketch the graphs  y = si n 3 x + ln x and  y = 1 + cos x  on the following axes for 0 < x ≤ 9.

\n

\n
[2]
\n
a.
\n
\n

Hence solve  si n 3 x + ln x cos x 1 < 0 in the range 0 < x ≤ 9.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

       A1A1

\n

Note: Award A1 for each correct curve, showing all local max & mins.

\n

Note: Award A0A0 for the curves drawn in degrees.

\n

[2 marks]

\n
a.
\n
\n

x  = 1.35, 4.35, 6.64       (M1)

\n

Note: Award M1 for attempt to find points of intersections between two curves.

\n

0 < x < 1.35      A1

\n

Note: Accept x  < 1.35.

\n

4.35 < x < 6.64       A1A1

\n

Note: Award A1 for correct endpoints, A1 for correct inequalities.

\n

Note: Award M1FTA1FTA0FTA0FT for 0 <  x  < 7.31.

\n

Note: Accept x  < 7.31.

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.AHL.TZ2.H_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing", "ahl-2-15-solutions-of-inequalities" ] }, { "Question": "
\n

Emily’s kite ABCD is hanging in a tree. The plane ABCDE is vertical.

\n

Emily stands at point E at some distance from the tree, such that EAD is a straight line and angle BED = 7°. Emily knows BD = 1.2 metres and angle BDA = 53°, as shown in the diagram

\n

\"N17/5/MATSD/SP1/ENG/TZ0/10\"

\n
\n

T is a point at the base of the tree. ET is a horizontal line. The angle of elevation of A from E is 41°.

\n
\n

Find the length of EB.

\n
[3]
\n
a.
\n
\n

Write down the angle of elevation of B from E.

\n
[1]
\n
b.
\n
\n

Find the vertical height of B above the ground.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

Units are required in parts (a) and (c).

\n

\n\n\n\nEB\n\n\n\nsin\n\n53\n\n\n\n\n\n\n\n\n\n\n=\n\n\n1.2\n\n\nsin\n\n7\n\n\n\n\n\n\n\n\n\n\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substitution into sine formula, (A1) for correct substitution.

\n

 

\n

\n(\n\nEB\n\n=\n)\n\n \n\n7.86\n\n m\n\n\n\n\n\nOR\n\n\n\n\n786\n\n cm \n\n(\n7.86385\n\n\n m\n\n\n\n\n\nOR\n\n\n\n\n786.385\n\n\n cm\n\n)\n     (A1)     (C3)

\n

[3 marks]

\n
a.
\n
\n

34°     (A1)     (C1)

\n

[1 mark]

\n
b.
\n
\n

Units are required in parts (a) and (c).

\n

\nsin\n\n\n34\n\n\n=\n\n\n\nheight\n\n\n\n7.86385\n\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into a trigonometric ratio.

\n

 

\n

\n(\n\nheight\n\n=\n)\n\n \n\n4.40\n\n m\n\n\n\n\n\nOR\n\n\n\n\n440\n\n cm \n\n(\n4.39741\n\n\n m\n\n\n\n\n\nOR\n\n\n\n\n439.741\n\n\n cm\n\n)\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Accept “BT” used for height. Follow through from parts (a) and (b). Use of 7.86 gives an answer of 4.39525….

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.1.SL.TZ0.T_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n2\n\n3\n\n\nx\n5\n\n\n\n\n2\n\n\nx\n3\n\n\n\n\n,\n\n\nx\n\n\nR\n\n,\n\n\nx\n\n0\n.

\n
\n

The graph of  y = f ( x )  has a local maximum at A. Find the coordinates of A.

\n
[5]
\n
a.
\n
\n

Show that there is exactly one point of inflexion, B, on the graph of  y = f ( x ) .

\n
[5]
\n
b.i.
\n
\n

The coordinates of B can be expressed in the form B ( 2 a , b × 2 3 a ) where a, b Q . Find the value of a and the value of b.

\n
[3]
\n
b.ii.
\n
\n

Sketch the graph of  y = f ( x ) showing clearly the position of the points A and B.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

attempt to differentiate      (M1)

\n

f ( x ) = 3 x 4 3 x      A1

\n

Note: Award M1 for using quotient or product rule award A1 if correct derivative seen even in unsimplified form, for example  f ( x ) = 15 x 4 × 2 x 3 6 x 2 ( 2 3 x 5 ) ( 2 x 3 ) 2 .

\n

3 x 4 3 x = 0      M1

\n

x 5 = 1 x = 1      A1

\n

A ( 1 , 5 2 )      A1

\n

[5 marks]

\n
a.
\n
\n

f ( x ) = 0      M1

\n

f ( x ) = 12 x 5 3 ( = 0 )      A1

\n

Note: Award A1 for correct derivative seen even if not simplified.

\n

x = 4 5 ( = 2 2 5 )      A1

\n

hence (at most) one point of inflexion      R1

\n

Note: This mark is independent of the two A1 marks above. If they have shown or stated their equation has only one solution this mark can be awarded.

\n

f ( x )  changes sign at  x = 4 5 ( = 2 2 5 )       R1

\n

so exactly one point of inflexion

\n

[5 marks]

\n
b.i.
\n
\n

x = 4 5 = 2 2 5 ( a = 2 5 )       A1

\n

f ( 2 2 5 ) = 2 3 × 2 2 2 × 2 6 5 = 5 × 2 6 5 ( b = 5 )      (M1)A1

\n

Note: Award M1 for the substitution of their value for  x into  f ( x ) .

\n

[3 marks]

\n
b.ii.
\n
\n

A1A1A1A1

\n

A1 for shape for x < 0
A1 for shape for x > 0
A1 for maximum at A
A1 for POI at B.

\n

Note: Only award last two A1s if A and B are placed in the correct quadrants, allowing for follow through.

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.AHL.TZ1.H_9", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-3-graphing", "sl-5-7-the-second-derivative" ] }, { "Question": "
\n

Sketch the graphs of  y = x 2 + 1 and  y = | x 2 | on the following axes.

\n

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

\n

straight line graph with correct axis intercepts      A1

\n

modulus graph: V shape in upper half plane      A1

\n

modulus graph having correct vertex and y-intercept      A1

\n

[3 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ2.H_2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing" ] }, { "Question": "
\n

The base of an electric iron can be modelled as a pentagon ABCDE, where:

\n

\n\n\n\n\n\nBCDE is a rectangle with sides of length \n\n(\nx\n+\n3\n)\n\n cm and \n\n(\nx\n+\n5\n)\n\n cm;\n\n\n\n\n\n\n\n\nABE is an isosceles triangle, with AB\n\n=\n\nAE and a height of \n\nx\n\n cm;\n\n\n\n\n\n\n\n\nthe area of ABCDE is 222 c\n\n\n\n\nm\n\n\n2\n\n\n\n\n.\n\n\n\n\n\n

\n

\"M17/5/MATSD/SP2/ENG/TZ1/02\"

\n
\n

Insulation tape is wrapped around the perimeter of the base of the iron, ABCDE.

\n
\n

F is the point on AB such that \n\nBF\n\n=\n\n8 cm\n\n. A heating element in the iron runs in a straight line, from C to F.

\n
\n

Write down an equation for the area of ABCDE using the above information.

\n
[2]
\n
a.i.
\n
\n

Show that the equation in part (a)(i) simplifies to \n3\n\n\nx\n2\n\n\n+\n19\nx\n\n414\n=\n0\n.

\n
[2]
\n
a.ii.
\n
\n

Find the length of CD.

\n
[2]
\n
b.
\n
\n

Show that angle \n\n\nB\n\n\nA\n^\n\n\nE\n\n\n=\n\n67.4\n\n\n, correct to one decimal place.

\n
[3]
\n
c.
\n
\n

Find the length of the perimeter of ABCDE.

\n
[3]
\n
d.
\n
\n

Calculate the length of CF.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

\n222\n=\n\n1\n2\n\nx\n(\nx\n+\n3\n)\n+\n(\nx\n+\n3\n)\n(\nx\n+\n5\n)\n     (M1)(M1)(A1)

\n

 

\n

Note:     Award (M1) for correct area of triangle, (M1) for correct area of rectangle, (A1) for equating the sum to 222.

\n

 

\n

OR

\n

\n222\n=\n(\nx\n+\n3\n)\n(\n2\nx\n+\n5\n)\n\n2\n\n(\n\n\n1\n4\n\n\n)\n\nx\n(\nx\n+\n3\n)\n     (M1)(M1)(A1)

\n

 

\n

Note:     Award (M1) for area of bounding rectangle, (M1) for area of triangle, (A1) for equating the difference to 222.

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

\n222\n=\n\n1\n2\n\n\n\nx\n2\n\n\n+\n\n3\n2\n\nx\n+\n\n\nx\n2\n\n\n+\n3\nx\n+\n5\nx\n+\n15\n     (M1)

\n

 

\n

Note:     Award (M1) for complete expansion of the brackets, leading to the final answer, with no incorrect working seen. The final answer must be seen to award (M1).

\n

 

\n

\n3\n\n\nx\n2\n\n\n+\n19\nx\n\n414\n=\n0\n     (AG)

\n

[2 marks]

\n
a.ii.
\n
\n

\nx\n=\n9\n\n \n\n\n(\n\n\nand \n\nx\n=\n\n\n\n46\n\n3\n\n\n)\n\n     (A1)

\n

\n\nCD\n\n=\n12\n\n (cm)\n\n     (A1)(G2)

\n

[2 marks]

\n
b.
\n
\n

\n\n1\n2\n\n(\n\ntheir \n\nx\n+\n3\n)\n=\n6\n     (A1)(ft)

\n

 

\n

Note:     Follow through from part (b).

\n

 

\n

\ntan\n\n\n(\n\n\n\n\n\nB\n\n\nA\n^\n\n\nE\n\n\n\n2\n\n\n)\n\n=\n\n6\n9\n\n     (M1)

\n

 

\n

Note:     Award (M1) for their correct substitutions in tangent ratio.

\n

 

\n

\n\n\nB\n\n\nA\n^\n\n\nE\n\n\n=\n67.3801\n\n\n\n\n     (A1)

\n

\n=\n\n67.4\n\n\n     (AG)

\n

 

\n

Note:     Do not award the final (A1) unless both the correct unrounded and rounded answers are seen.

\n

 

\n

OR

\n

\n\n1\n2\n\n(\n\ntheir \n\nx\n+\n3\n)\n=\n6\n     (A1)(ft)

\n

\ntan\n\n(\n\n\nA\n\n\nB\n^\n\n\nE\n\n\n)\n=\n\n9\n6\n\n     (M1)

\n

 

\n

Note:     Award (M1) for their correct substitutions in tangent ratio.

\n

 

\n

\n\n\nB\n\n\nA\n^\n\n\nE\n\n\n=\n\n180\n\n\n\n2\n(\n\n\nA\n\n\nB\n^\n\n\nE\n\n\n)\n

\n

\n\n\nB\n\n\nA\n^\n\n\nE\n\n\n=\n67.3801\n\n\n\n\n     (A1)

\n

\n=\n\n67.4\n\n\n     (AG)

\n

 

\n

Note:     Do not award the final (A1) unless both the correct unrounded and rounded answers are seen.

\n

 

\n

[3 marks]

\n
c.
\n
\n

\n2\n\n\n\n9\n2\n\n\n+\n\n\n6\n2\n\n\n\n+\n12\n+\n2\n(\n14\n)\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for correct substitution into Pythagoras. Award (M1) for the addition of 5 sides of the pentagon, consistent with their \nx\n.

\n

 

\n

\n61.6\n\n (cm) \n\n\n(\n\n61.6333\n\n\n (cm)\n\n\n)\n\n     (A1)(ft)(G3)

\n

 

\n

Note:     Follow through from part (b).

\n

 

\n

[3 marks]

\n
d.
\n
\n

\n\n\nF\n\n\nB\n^\n\n\nC\n\n\n=\n90\n+\n\n(\n\n\n\n180\n\n67.4\n\n2\n\n\n)\n\n\n \n\n(\n=\n\n146.3\n\n\n)\n     (M1)

\n

OR

\n

\n180\n\n\n\n67.4\n\n2\n\n     (M1)

\n

\n\n\nC\n\n\n\n\n\nF\n\n2\n\n\n=\n\n\n8\n2\n\n\n+\n\n\n14\n2\n\n\n\n2\n(\n8\n)\n(\n14\n)\ncos\n\n(\n\n146.3\n\n\n)\n     (M1)(A1)(ft)

\n

 

\n

Note:     Award (M1) for substituted cosine rule formula and (A1) for correct substitutions. Follow through from part (b).

\n

 

\n

\n\nCF\n\n=\n21.1\n\n (cm) \n\n(\n21.1271\n\n)\n     (A1)(ft)(G3)

\n

OR

\n

\n\n\nG\n\n\nB\n^\n\n\nF\n\n\n=\n\n\n67.4\n\n2\n\n=\n\n33.7\n\n\n     (A1)

\n

 

\n

Note:     Award (A1) for angle \n\n\nG\n\n\nB\n^\n\n\nF\n\n\n=\n\n33.7\n\n\n, where G is the point such that CG is a projection/extension of CB and triangles BGF and CGF are right-angled triangles. The candidate may use another variable.

\n

\"M17/5/MATSD/SP2/ENG/TZ1/02.e/M\"

\n

 

\n

\n\nGF\n\n=\n8\nsin\n\n\n33.7\n\n\n=\n4.4387\n\n\n\n\n\nAND\n\n\n\n\n\nBG\n\n=\n8\ncos\n\n\n33.7\n\n\n=\n6.6556\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into trig formulas to find both GF and BG.

\n

 

\n

\n\nC\n\n\n\n\nF\n\n2\n\n\n=\n\n(\n14\n+\n6.6556\n\n\n)\n2\n\n\n+\n\n(\n4.4387\n\n\n)\n2\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into Pythagoras formula to find CF.

\n

 

\n

\n\nCF\n\n=\n21.1\n\n (cm) \n\n(\n21.1271\n\n)\n     (A1)(ft)(G3)

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "17M.2.SL.TZ1.T_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Consider the function \nf\n defined by \nf\n(\nx\n)\n=\n3\nx\narccos\n\n(\nx\n)\n where \n\n1\n\nx\n\n1\n.

\n
\n

Sketch the graph of \nf\n indicating clearly any intercepts with the axes and the coordinates of any local maximum or minimum points.

\n
[3]
\n
a.
\n
\n

State the range of \nf\n.

\n
[2]
\n
b.
\n
\n

Solve the inequality \n\n|\n\n3\nx\narccos\n\n(\nx\n)\n\n|\n\n>\n1\n.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"N16/5/MATHL/HP2/ENG/TZ0/05.a/M\"

\n

correct shape passing through the origin and correct domain     A1

\n

 

\n

Note: Endpoint coordinates are not required. The domain can be indicated by \n\n1\n and 1 marked on the axis.

\n

\n(\n0.652\n,\n\n \n\n1.68\n)\n    A1

\n

two correct intercepts (coordinates not required)     A1

\n

 

\n

Note: A graph passing through the origin is sufficient for \n(\n0\n,\n\n \n\n0\n)\n.

\n

 

\n

[3 marks]

\n
a.
\n
\n

\n[\n\n9.42\n,\n\n \n\n1.68\n]\n\n \n\n(\n\nor \n\n\n3\nπ\n,\n\n \n\n1.68\n]\n)\n    A1A1

\n

 

\n

Note: Award A1A0 for open or semi-open intervals with correct endpoints. Award A1A0 for closed intervals with one correct endpoint.

\n

 

\n

[2 marks]

\n
b.
\n
\n

attempting to solve either \n\n|\n\n3\nx\narccos\n\n(\nx\n)\n\n|\n\n>\n1\n (or equivalent) or \n\n|\n\n3\nx\narccos\n\n(\nx\n)\n\n|\n\n=\n1\n (or equivalent) (eg. graphically)     (M1)

\n

\"N16/5/MATHL/HP2/ENG/TZ0/05.c/M\"

\n

\nx\n=\n\n0.189\n,\n\n \n\n0.254\n,\n\n \n\n0.937\n    (A1)

\n

\n\n1\n\nx\n<\n\n0.189\n\n or \n\n0.254\n<\nx\n<\n0.937\n    A1A1

\n

 

\n

Note: Award A0 for \nx\n<\n\n0.189\n.

\n

 

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.2.AHL.TZ0.H_5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

The graph of \ny\n=\n\nf\n\n\n\n(\nx\n)\n\n, 0 ≤ \nx\n ≤ 5 is shown in the following diagram. The curve intercepts the \nx\n-axis at (1, 0) and (4, 0) and has a local minimum at (3, −1).

\n

\n
\n

The shaded area enclosed by the curve \ny\n=\n\nf\n\n\n\n(\nx\n)\n\n, the \nx\n-axis and the \ny\n-axis is 0.5. Given that \nf\n\n(\n0\n)\n\n=\n3\n,

\n
\n

The area enclosed by the curve \ny\n=\n\nf\n\n\n\n(\nx\n)\n\n and the \nx\n-axis between \nx\n=\n1\n and \nx\n=\n4\n is 2.5 .

\n
\n

Write down the x -coordinate of the point of inflexion on the graph of  y = f ( x ) .

\n
[1]
\n
a.
\n
\n

find the value of  f ( 1 ) .

\n
[3]
\n
b.
\n
\n

find the value of  f ( 4 ) .

\n
[2]
\n
c.
\n
\n

Sketch the curve y = f ( x ) , 0 ≤ x ≤ 5 indicating clearly the coordinates of the maximum and minimum points and any intercepts with the coordinate axes.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

3     A1

\n

[1 mark]

\n
a.
\n
\n

attempt to use definite integral of  f ( x )         (M1)

\n

0 1 f ( x ) d x = 0.5

\n

f ( 1 ) f ( 0 ) = 0.5         (A1)

\n

f ( 1 ) = 0.5 + 3

\n

= 3.5      A1

\n

[3 marks]

\n
b.
\n
\n

1 4 f ( x ) d x = 2.5        (A1)

\n

Note: (A1) is for −2.5.

\n

f ( 4 ) f ( 1 ) = 2.5

\n

f ( 4 ) = 3.5 2.5

\n

= 1      A1

\n

[2 marks]

\n
c.
\n
\n

    A1A1A1

\n

A1 for correct shape over approximately the correct domain
A1 for maximum and minimum (coordinates or horizontal lines from 3.5 and 1 are required),
A1 for y -intercept at 3

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.1.AHL.TZ1.H_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-7-the-second-derivative", "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A ladder on a fire truck has its base at point B which is 4 metres above the ground. The ladder is extended and its other end rests on a vertical wall at point C, 16 metres above the ground. The horizontal distance between B and C is 9 metres.

\n

\n
\n

Find the angle of elevation from B to C.

\n
[3]
\n
a.
\n
\n

A second truck arrives whose ladder, when fully extended, is 30 metres long. The base of this ladder is also 4 metres above the ground. For safety reasons, the maximum angle of elevation that the ladder can make is 70º.

\n

Find the maximum height on the wall that can be reached by the ladder on the second truck.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

tan B = 12 9     (A1)(M1)

\n

Note: Award (A1) for 12 seen, (M1) for correct substitution into tan (or equivalent). Accept equivalent methods, such as Pythagoras, to find BC and correct substitution into other trig ratios. If ta n 1 ( 16 9 ) seen award (A0)(M1)(A0).

\n

53.1°  (53.1301…°)     (A1)  (C3)

\n

Note: If radians are used the answer is 0.927295…; award at most (A1)(M1)(A0).

\n

[3 marks]

\n
a.
\n
\n

\n30\n\n\nsin\n\n\n\n70\n\n\n+\n4\n       (M1)(M1)

\n

Note: Award (M1) for \n\nsin\n\n\n\n70\n\n\n=\n\nx\n\n30\n\n\n (or equivalent) and (M1) for adding 4.

\n

32.2  (32.1907…) (m)    (A1)  (C3)

\n

Note: If radians are used the answer is 27.2167…; award at most (M1)(M1)(A0).

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.SL.TZ2.T_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Consider the differential equation \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n4\n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n\nx\ny\n\n\n\n\nx\n2\n\n\n\n\n, with \ny\n=\n2\n when \nx\n=\n1\n.

\n
\n

Use Euler’s method, with step length h = 0.1 , to find an approximate value of y when x = 1.4 .

\n
[5]
\n
a.
\n
\n

Sketch the isoclines for  d y d x = 4 .

\n
[3]
\n
b.
\n
\n

Express  m 2 2 m + 4  in the form  ( m a ) 2 + b , where  a b Z .

\n
[1]
\n
c.i.
\n
\n

Solve the differential equation, for x > 0 , giving your answer in the form y = f ( x ) .

\n
[10]
\n
c.ii.
\n
\n

Sketch the graph of  y = f ( x ) for  1 x 1.4  .

\n
[1]
\n
c.iii.
\n
\n

With reference to the curvature of your sketch in part (c)(iii), and without further calculation, explain whether you conjecture f ( 1.4 ) will be less than, equal to, or greater than your answer in part (a).

\n
[2]
\n
c.iv.
\n
", "Markscheme": "
\n

       (M1)(A1)(A1)(A1)A1

\n

y ( 1.4 ) 5.34

\n

Note: Award A1 for each correct y value.
For the intermediate y values, accept answers that are accurate to 2 significant figures.
The final y value must be accurate to 3 significant figures or better.

\n

[5 marks]

\n
a.
\n
\n

attempt to solve  4 x 2 + y 2 x y x 2 = 4         (M1)

\n

y 2 x y = 0

\n

y ( y x ) = 0

\n

y = 0   or  y = x

\n

        A1A1

\n

[3 marks]

\n
b.
\n
\n

m 2 2 m + 4 = ( m 1 ) 2 + 3 ( a = 1 , b = 3 )         A1

\n

[1 mark]

\n
c.i.
\n
\n

recognition of homogeneous equation,
let  y = v x              M1

\n

the equation can be written as

\n

v + x d v d x = 4 + v 2 v          (A1)

\n

x d v d x = v 2 2 v + 4

\n

1 v 2 2 v + 4 d v = 1 x d x              M1

\n

Note: Award M1 for attempt to separate the variables.

\n

1(v1)2+3dv=1xdx from part (c)(i)             M1

\n

1 3 arctan ( v 1 3 ) = ln x ( + c )           A1A1

\n

x = 1 , y = 2 v = 2

\n

1 3 arctan ( 1 3 ) = ln 1 + c              M1

\n

Note: Award M1 for using initial conditions to find c .

\n

c = π 6 3 ( = 0.302 )         A1

\n

arctan ( v 1 3 ) = 3 ln x + π 6

\n

substituting  v = y x              M1

\n

Note: This M1 may be awarded earlier.

\n

y = x ( 3 tan ( 3 ln x + π 6 ) + 1 )         A1

\n

[10 marks]

\n
c.ii.
\n
\n

\n

curve drawn over correct domain       A1

\n

 

\n

[1 mark]

\n
c.iii.
\n
\n

the sketch shows that f is concave up       A1

\n

Note: Accept f is increasing.

\n

this means the tangent drawn using Euler’s method will give an underestimate of the real value, so f ( 1.4 ) > estimate in part (a)       R1

\n

Note: The R1 is dependent on the A1.

\n

[2 marks]

\n
c.iv.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
\n[N/A]\n
c.iv.
\n
", "question_id": "19N.3.AHL.TZ0.HCA_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n\nx\n4\n\n\n\n6\n\n\nx\n2\n\n\n\n2\nx\n+\n4\n\nx\n\n\nR\n\n.

\n

The graph of \nf\n is translated two units to the left to form the function \ng\n\n(\nx\n)\n\n.

\n

Express \ng\n\n(\nx\n)\n\n in the form \na\n\n\nx\n4\n\n\n+\nb\n\n\nx\n3\n\n\n+\nc\n\n\nx\n2\n\n\n+\nd\nx\n+\ne\n where \na\n\nb\n\nc\n\nd\n\ne\n\n\nZ\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ng\n\n(\nx\n)\n\n=\nf\n\n(\n\nx\n+\n2\n\n)\n\n\n(\n\n=\n\n\n\n\n(\n\nx\n+\n2\n\n)\n\n\n4\n\n\n\n6\n\n\n\n\n(\n\nx\n+\n2\n\n)\n\n\n2\n\n\n\n2\n\n(\n\nx\n+\n2\n\n)\n\n+\n4\n\n)\n\n      M1

\n

attempt to expand \n\n\n\n\n\n(\n\nx\n+\n2\n\n)\n\n\n4\n\n\n\n      M1

\n

\n\n\n\n(\n\nx\n+\n2\n\n)\n\n4\n\n\n=\n\n\nx\n4\n\n\n+\n4\n\n(\n\n2\n\n\nx\n3\n\n\n\n)\n\n+\n6\n\n(\n\n\n\n2\n2\n\n\n\n\nx\n2\n\n\n\n)\n\n+\n4\n\n(\n\n\n\n2\n3\n\n\nx\n\n)\n\n+\n\n\n2\n4\n\n\n       (A1)

\n

\n=\n\n\nx\n4\n\n\n+\n8\n\n\nx\n3\n\n\n+\n24\n\n\nx\n2\n\n\n+\n32\nx\n+\n16\n      A1

\n

\ng\n\n(\nx\n)\n\n=\n\n\nx\n4\n\n\n+\n8\n\n\nx\n3\n\n\n+\n24\n\n\nx\n2\n\n\n+\n32\nx\n+\n16\n\n6\n\n(\n\n\n\nx\n2\n\n\n+\n4\nx\n+\n4\n\n)\n\n\n2\nx\n\n4\n+\n4\n

\n

\n=\n\n\nx\n4\n\n\n+\n8\n\n\nx\n3\n\n\n+\n18\n\n\nx\n2\n\n\n+\n6\nx\n\n8\n      A1

\n

Note: For correct expansion of \nf\n\n(\n\nx\n\n2\n\n)\n\n=\n\n\nx\n4\n\n\n\n8\n\n\nx\n3\n\n\n+\n18\n\n\nx\n2\n\n\n\n10\nx\n award max  M0M1(A1)A0A1.

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ2.H_3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-11-transformation-of-functions" ] }, { "Question": "
\n

The voltage \nv\n in a circuit is given by the equation

\n

\nv\n\n(\nt\n)\n\n=\n3\n\n\nsin\n\n\n(\n\n100\nπ\nt\n\n)\n\n\nt\n\n0\n where \nt\n is measured in seconds.

\n
\n

The current \ni\n in this circuit is given by the equation

\n

\ni\n\n(\nt\n)\n\n=\n2\n\n\nsin\n\n\n(\n\n100\nπ\n\n(\n\nt\n+\n0.003\n\n)\n\n\n)\n\n.

\n
\n

The power \np\n in this circuit is given by \np\n\n(\nt\n)\n\n=\nv\n\n(\nt\n)\n\n×\ni\n\n(\nt\n)\n\n.

\n
\n

The average power \n\n\np\n\na\nv\n\n\n\n in this circuit from \nt\n=\n0\n to \nt\n=\nT\n is given by the equation

\n

\n\n\np\n\na\nv\n\n\n\n\n(\nT\n)\n\n=\n\n1\nT\n\n\n\n0\nT\n\n\np\n\n(\nt\n)\n\n\nd\n\nt\n\n, where \nT\n>\n0\n.

\n
\n

Write down the maximum and minimum value of \nv\n.

\n
[2]
\n
a.
\n
\n

Write down two transformations that will transform the graph of \ny\n=\nv\n\n(\nt\n)\n\n onto the graph of \ny\n=\ni\n\n(\nt\n)\n\n.

\n
[2]
\n
b.
\n
\n

Sketch the graph of \ny\n=\np\n\n(\nt\n)\n\n for 0 ≤ \nt\n ≤ 0.02 , showing clearly the coordinates of the first maximum and the first minimum.

\n
[3]
\n
c.
\n
\n

Find the total time in the interval 0 ≤ \nt\n ≤ 0.02 for which \np\n\n(\nt\n)\n\n ≥ 3.

\n

 

\n
[3]
\n
d.
\n
\n

Find \n\n\np\n\na\nv\n\n\n\n(0.007).

\n

 

\n
[2]
\n
e.
\n
\n

With reference to your graph of \ny\n=\np\n\n(\nt\n)\n\n explain why \n\n\np\n\na\nv\n\n\n\n\n(\nT\n)\n\n > 0 for all \nT\n > 0.

\n

 

\n
[2]
\n
f.
\n
\n

Given that \np\n\n(\nt\n)\n\n can be written as \np\n\n(\nt\n)\n\n=\na\n\n\nsin\n\n\n(\n\nb\n\n(\n\nt\n\nc\n\n)\n\n\n)\n\n+\nd\n where \na\n\nb\n\nc\n\nd\n > 0, use your graph to find the values of \na\n\nb\n\nc\n and \nd\n.

\n

 

\n
[6]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

3, −3       A1A1 

\n

[2 marks]

\n
a.
\n
\n

stretch parallel to the \ny\n-axis (with \nx\n-axis invariant), scale factor \n\n2\n3\n\n       A1

\n

translation of \n\n(\n\n\n\n\n\n\n0.003\n\n\n\n\n\n0\n\n\n\n\n)\n\n  (shift to the left by 0.003)      A1

\n

Note: Can be done in either order.

\n

[2 marks]

\n
b.
\n
\n

\n

correct shape over correct domain with correct endpoints       A1
first maximum at (0.0035, 4.76)       A1
first minimum at (0.0085, −1.24)       A1

\n

[3 marks]

\n
c.
\n
\n

\np\n ≥ 3 between \nt\n = 0.0016762 and 0.0053238 and \nt\n = 0.011676 and 0.015324       (M1)(A1)

\n

Note: Award M1A1 for either interval.

\n

= 0.00730       A1

\n

[3 marks]

\n
d.
\n
\n

\n\n\np\n\na\nv\n\n\n\n=\n\n1\n\n0.007\n\n\n\n\n0\n\n0.007\n\n\n\n6\n\n\nsin\n\n\n(\n\n100\nπ\nt\n\n)\n\n\n\nsin\n\n\n(\n\n100\nπ\n\n(\n\nt\n+\n0.003\n\n)\n\n\n)\n\n\nd\n\nt\n     (M1)

\n

= 2.87       A1

\n

[2 marks]

\n
e.
\n
\n

in each cycle the area under the \nt\n axis is smaller than area above the \nt\n axis      R1

\n

the curve begins with the positive part of the cycle       R1

\n

[2 marks]

\n
f.
\n
\n

\na\n=\n\n\n4.76\n\n\n(\n\n\n1.24\n\n)\n\n\n2\n\n       (M1)

\n

\na\n=\n3.00\n       A1

\n

\nd\n=\n\n\n4.76\n+\n\n(\n\n\n1.24\n\n)\n\n\n2\n\n

\n

\nd\n=\n1.76\n       A1

\n

\nb\n=\n\n\n2\nπ\n\n\n0.01\n\n\n

\n

\nb\n=\n628\n\n(\n\n=\n200\nπ\n\n)\n\n       A1

\n

\nc\n=\n0.0035\n\n\n\n0.01\n\n4\n\n       (M1)

\n

\nc\n=\n0.00100\n       A1

\n

[6 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "19M.2.AHL.TZ1.H_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

The derivative of a function f is given by f'x=3x.

\n

Given that f1=3, find the value of f4.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

correct working      (A1)

\n

eg   −5 + (8 − 1)(3)

\n

u8 = 16     A1 N2

\n

 

\n

[2 marks]

\n

METHOD 1

\n

fx=3xdx       (A1)

\n

attempts to integrate       (M1)

\n

fx=2x32+C  =2xx+C       A1

\n

uses f1=3 to obtain 3=2132+C and so C=1       M1

\n

substitutes x=4 into their expression for fx       (M1)

\n

so f4=17       A1

\n

 

\n

METHOD 2

\n

14f'xdx=143xdx       (A1)

\n

attempts to integrate both sides       (M1)

\n

fx14=2x3214       A1

\n

f4-f1=16-2       M1

\n

uses f1=3 to find their value of f4       (M1)

\n

f4-3=16-2

\n

so f4=17       A1

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.1.SL.TZ0.1", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

In parts (b) and (c), \n\n\n\n(\n\na\nb\nc\n\n\n)\n\nn\n\n\n denotes the number \n\na\nb\nc\n\n\n written in base \nn\n, where \nn\n\n\n\n\nZ\n\n+\n\n\n. For example, \n\n\n\n(\n\n359\n\n)\n\nn\n\n\n=\n3\n\n\nn\n2\n\n\n+\n5\nn\n+\n9\n.

\n
\n

State Fermat’s little theorem.

\n
[2]
\n
a.i.
\n
\n

Find the remainder when  15 1207 is divided by  13 .

\n
[5]
\n
a.ii.
\n
\n

Convert  ( 7 A 2 ) 16 to base 5 , where  ( A ) 16 = ( 10 ) 10 .

\n
[4]
\n
b.
\n
\n

Consider the equation ( 1251 ) n + ( 30 ) n = ( 504 ) n + ( 504 ) n .

\n

Find the value of n .

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

EITHER

\n

a p a ( mod p )          A1

\n

where p is prime         A1

\n

 

\n

OR

\n

a p 1 1 ( mod p )          A1

\n

where p is prime and p does not divide a (or equivalent statement)         A1

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

15 1207 2 1207 ( mod 13 )

\n

2 12 1 ( mod 13 )         (M1)(A1)

\n

2 1207 = ( 2 12 ) 100 2 7         (M1)

\n

2 1207 ( 2 7 ) 11 ( mod 13 )         (M1)A1

\n

the remainder is 11

\n

Note: Award as above for using 15 instead of 2 .

\n

[5 marks]

\n
a.ii.
\n
\n

( 7 A 2 ) 16 = 7 × 16 2 + 10 × 16 + 2            M1

\n

= 1954          A1

\n

EITHER

\n

5 | 1954 _

\n

        390 r 4

\n

          78 r 0

\n

          15 r 3            M1

\n

            3 r 0

\n

            0 r 3

\n

OR

\n

1954 = 3 × 5 4 + 0 × 5 3 + 3 × 5 2 + 0 × 5 1 + 4            M1

\n

THEN

\n

( 7 A 2 ) 16 = ( 30304 ) 5          A1

\n

 

\n

[4 marks]

\n
b.
\n
\n

the equation can be written as

\n

n 3 + 2 n 2 + 5 n + 1 + 3 n = 2 ( 5 n 2 + 4 )            M1A1

\n

n 3 8 n 2 + 8 n 7 = 0            (M1)

\n

Note: The (M1) is for an attempt to solve the original equation.

\n

n = 7          A1

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.3.AHL.TZ0.HDM_2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-7-laws-of-exponents-and-logs" ] }, { "Question": "
\n

Solve the equation 2lnx=ln9+4. Give your answer in the form x=peq where p,q+.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

 

\n

METHOD 1

\n

2lnx-ln9=4

\n

uses mlnx=lnxm       (M1)

\n

lnx2-ln9=4

\n

uses lna-lnb=lnab       (M1)

\n

lnx29=4

\n

x29=e4       A1

\n

x2=9e4x=9e4  x>0       A1

\n

x=3e2  p=3, q=2       A1

\n

 

\n

METHOD 2

\n

expresses 4 as 4lne and uses lnxm=mlnx       (M1)

\n

2lnx=2ln3+4lne  lnx=ln3+2lne       A1

\n

uses 2lne=lne2 and lna+lnb=lnab       (M1)

\n

lnx=ln3e2       A1

\n

x=3e2  p=3, q=2       A1

\n

 

\n

METHOD 3

\n

expresses 4 as 4lne and uses mlnx=lnxm       (M1)

\n

lnx2=ln32+lne4       A1

\n

uses lna+lnb=lnab       (M1)

\n

lnx2=ln32e4

\n

x2=32e4x=32e4  x>0       A1

\n

so x=3e2  x>0  p=3, q=2       A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.1.SL.TZ0.2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-7-laws-of-exponents-and-logs" ] }, { "Question": "
\n

The following table shows the probability distribution of a discrete random variable X where x=1,2,3,4.

\n

\n

Find the value of k, justifying your answer.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

uses PX=x=1       (M1)

\n

k2+7k+2+-2k+3k2=1

\n

4k2+5k+1=0       A1

\n

 

\n

EITHER

\n

attempts to factorize their quadratic       M1

\n

k+14k+1=0

\n

 

\n

OR

\n

attempts use of the quadratic formula on their equation       M1

\n

k=-5±52-4418 =-5±38

\n

 

\n

THEN

\n

k=-1,-14       A1

\n

rejects k=-1 as this value leads to invalid probabilities, for example, PX=2=-5<0       R1

\n

so k=-14       A1

\n

 

\n

Note: Award R0A1 if k=-14 is stated without a valid reason given for rejecting k=-1.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.1.SL.TZ0.3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-6-quadratic-function" ] }, { "Question": "
\n

The first three terms of an arithmetic sequence are u1,5u1-8 and 3u1+8.

\n
\n

Show that u1=4.

\n
[2]
\n
a.
\n
\n

Prove that the sum of the first n terms of this arithmetic sequence is a square number.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

EITHER

\n

uses u2-u1=u3-u2       (M1)

\n

5u1-8-u1=3u1+8-5u1-8

\n

6u1=24       A1

\n

 

\n

OR

\n

uses u2=u1+u32       (M1)

\n

5u1-8=u1+3u1+82

\n

3u1=12       A1

\n

 

\n

THEN

\n

so u1=4       AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

d=8       (A1)

\n

uses Sn=n22u1+n-1d       M1

\n

Sn=n28+8n-1       A1

\n

=4n2

\n

=2n2       A1

\n

 

\n

Note: The final A1 can be awarded for clearly explaining that 4n2 is a square number.

\n

 

\n

so sum of the first n terms is a square number       AG

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "EXN.1.SL.TZ0.4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Peter, the Principal of a college, believes that there is an association between the score in a Mathematics test, \nX\n, and the time taken to run 500 m, \nY\n seconds, of his students. The following paired data are collected.

\n

\n

It can be assumed that \n\n(\n\nX\n\n\n\nY\n\n)\n\n follow a bivariate normal distribution with product moment correlation coefficient \nρ\n.

\n
\n

State suitable hypotheses H 0 and H 1 to test Peter’s claim, using a two-tailed test.

\n
[1]
\n
a.i.
\n
\n

Carry out a suitable test at the 5 % significance level. With reference to the  p -value, state your conclusion in the context of Peter’s claim.

\n
[4]
\n
a.ii.
\n
\n

Peter uses the regression line of y on x as y = 0.248 x + 83.0 and calculates that a student with a Mathematics test score of 73 will have a running time of 101 seconds. Comment on the validity of his calculation.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

H 0 : ρ = 0     H 1 : ρ 0        A1

\n

Note: It must be ρ .

\n

[1 mark]

\n
a.i.
\n
\n

p = 0.649        A2

\n

Note: Accept anything that rounds to 0.65

\n

0.649 > 0.05        R1

\n

hence, we accept  H 0 and conclude that Peter’s claim is wrong         A1

\n

Note: The A mark depends on the R mark and the answer must be given in context. Follow through the p -value in part (b).

\n

[4 marks]

\n
a.ii.
\n
\n

a statement along along the lines of ‘(we have accepted that) the two variables are independent’ or ‘the two variables are weakly correlated’       R1

\n

a statement along the lines of ‘the use of the regression line is invalid’ or ‘it would give an inaccurate result’       R1

\n

Note: Award the second R1 only if the first R1 is awarded.

\n

Note: FT the conclusion in(a)(ii). If a candidate concludes that the claim is correct, mark as follows: (as we have accepted H1) the 2 variables are dependent and 73 lies in the range of x values R1, hence the use of the regression line is valid R1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.3.AHL.TZ0.HSP_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The functions f and g are defined for x by fx=x-2 and gx=ax+b, where a,b.

\n

Given that fg2=-3 and gf1=5, find the value of a and the value of b.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

fgx=ax+b-2       (M1)

\n

fg2=-32a+b-2=-3 2a+b=-1       A1

\n

gfx=ax-2+b       (M1)

\n

gf1=5-a+b=5       A1

\n

a valid attempt to solve their two linear equations for a and b       M1

\n

so a=-2 and b=3       A1

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.1.SL.TZ0.5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

The following diagram shows the graph of y=4-x2, 0x2 and rectangle ORST. The rectangle has a vertex at the origin O, a vertex on the y-axis at the point R0,y, a vertex on the x-axis at the point Tx,0 and a vertex at point Sx,y on the graph.

\n

\n

Let P represent the perimeter of rectangle ORST.

\n
\n

Let A represent the area of rectangle ORST.

\n
\n

Show that P=-2x2+2x+8.

\n
[2]
\n
a.
\n
\n

Find the dimensions of rectangle ORST that has maximum perimeter and determine the value of the maximum perimeter.

\n
[6]
\n
b.
\n
\n

Find an expression for A in terms of x.

\n
[2]
\n
c.
\n
\n

Find the dimensions of rectangle ORST that has maximum area.

\n
[5]
\n
d.
\n
\n

Determine the maximum area of rectangle ORST.

\n
[1]
\n
e.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

P=2x+2y        (A1)

\n

=2x+24-x2        A1

\n

so  P=-2x2+2x+8        AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

EITHER

\n

uses the axis of symmetry of a quadratic        (M1)

\n

x=-22-2

\n

 

\n

OR

\n

forms dPdx=0        (M1)

\n

-4x+2=0

\n

 

\n

THEN

\n

x=12        A1

\n

substitutes their value of x into y=4-x2        (M1)

\n

y=4-122

\n

y=154        A1

\n

so the dimensions of rectangle ORST of maximum perimeter are 12 by 154

\n

 

\n

EITHER

\n

substitutes their value of x into P=-2x2+2x+8        (M1)

\n

P=-2122+212+8

\n

 

\n

OR

\n

substitutes their values of x and y into P=2x+2y        (M1)

\n

P=212+2154

\n

P=172        A1

\n

so the maximum perimeter is 172

\n

 

\n

METHOD 2

\n

attempts to complete the square         M1

\n

P=-2x-122+172        A1

\n

x=12        A1

\n

substitutes their value of x into y=4-x2        (M1)

\n

y=4-122

\n

y=154        A1

\n

so the dimensions of rectangle ORST of maximum perimeter are 12 by 154

\n

P=172        A1

\n

so the maximum perimeter is 172        

\n

 

\n

[6 marks]

\n
b.
\n
\n

substitutes y=4-x2 into A=xy        (M1)

\n

A=x4-x2  =4x-x3        A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

dAdx=4-3x2        A1

\n

attempts to solve their dAdx=0 for x        (M1)

\n

4-3x2=0

\n

x=23=233 x>0        A1

\n

substitutes their (positive) value of x into y=4-x2        (M1)

\n

y=4-232

\n

y=83        A1

\n

 

\n

[5 marks]

\n
d.
\n
\n

A=1633=1639        A1

\n

 

\n

[1 mark]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "EXN.1.SL.TZ0.7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

A geometric sequence has  u 4 = 70 and u 7 = 8.75 . Find the second term of the sequence.

\n
", "Markscheme": "
\n

u 1 r 3 = 70 u 1 r 6 = 8.75      (M1)

\n

r 3 = 8.75 70 = 0.125        (A1)

\n

r = 0.5        (A1)

\n

valid attempt to find  u 2        (M1)

\n

for example:  u 1 = 70 0.125 = 560

\n

u 2 = 560 × 0.5

\n

     = 280        A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.2.AHL.TZ0.H_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

A random variable \nX\n has probability density function

\n

\nf\n\n(\nx\n)\n\n=\n\n{\n\n\n\n\n\n3\na\n\n\n\n\n,\n\n\n\n\n0\n\nx\n<\n2\n\n\n\n\n\n\n\n\n\n\na\n\n(\n\nx\n\n5\n\n)\n\n\n(\n\n1\n\nx\n\n)\n\n\n\n\n\n,\n\n\n\n\n2\n\nx\n\nb\n\n\n\n\na\n\n\n\nb\n\n\n\n\nR\n\n+\n\n\n\n\n\n3\n<\nb\n\n5.\n\n\n\n\n\n0\n\n\n\n,\n\n\n\n\n\notherwise\n\n\n\n\n\n\n\n\n\n\n\n\n

\n

 

\n
\n

Consider the case where \nb\n=\n5\n.

\n
\n

Find the value of

\n
\n

Find, in terms of a , the probability that X lies between 1 and 3.

\n
[4]
\n
a.
\n
\n

Sketch the graph of f . State the coordinates of the end points and any local maximum or minimum points, giving your answers in terms of a .

\n
[4]
\n
b.
\n
\n

a .

\n
[4]
\n
c.i.
\n
\n

E ( X ) .

\n
[3]
\n
c.ii.
\n
\n

the median of X .

\n
[4]
\n
c.iii.
\n
", "Markscheme": "
\n

( P ( 1 < X < 3 ) = ) 1 2 3 a d x + a 2 3 x 2 + 6 x 5 d x        (M1)(A1)(A1)

\n

= 3 a + 11 3 a

\n

= 20 3 a ( = 6.67 a )         A1

\n

[4 marks]

\n
a.
\n
\n

        A4

\n

award A1 for (0, 3 a ), A1 for continuity at (2, 3 a ), A1 for maximum at (3, 4 a ), A1 for (5, 0)

\n

Note: Award A3 if correct four points are not joined by a straight line and a quadratic curve.

\n

[4 marks]

\n
b.
\n
\n

P ( 0 X 5 ) = 6 a + a 2 5 x 2 + 6 x 5 d x        (M1)

\n

= 15 a        (A1)

\n

15 a = 1        (M1)

\n

a = 1 15 ( = 0.0667 )        A1

\n

[4 marks]

\n
c.i.
\n
\n

E ( X ) = 1 5 0 2 x d x + 1 15 2 5 x 3 + 6 x 2 5 x d x        (M1)(A1)

\n

= 2.35       A1

\n

[3 marks]

\n
c.ii.
\n
\n

attempt to use  0 m f ( x ) d x = 0.5        (M1)

\n

0.4 + a 2 m x 2 + 6 x 5 d x = 0.5        (A1)

\n

a 2 m x 2 + 6 x 5 d x = 0.1

\n

attempt to solve integral using GDC and/or analytically       (M1)

\n

1 15 [ 1 3 x 3 + 3 x 2 5 x ] 2 m = 0.1

\n

m = 2.44        A1

\n

[4 marks]

\n
c.iii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
", "question_id": "19N.2.AHL.TZ0.H_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n\na\nx\n+\n1\n\n\nb\nx\n+\nc\n\n\n, \nx\n\n\n\nc\nb\n\n, where \na\n\nb\n\nc\n\n\nZ\n\n.

\n

The following graph shows the curve \ny\n=\n\n\n\n(\n\nf\n\n(\nx\n)\n\n\n)\n\n2\n\n\n. It has asymptotes at \nx\n=\np\n and \ny\n=\nq\n and meets the \nx\n-axis at A.

\n

\n
\n

On the following axes, sketch the two possible graphs of  y = f ( x )  giving the equations of any asymptotes in terms of  p and  q .

\n

\n
[4]
\n
a.
\n
\n

Given that  p = 4 3 q = 4 9 and A has coordinates  ( 1 2 , 0 ) , determine the possible sets of values for  a b and  c .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

\n

either graph passing through (or touching) A        A1

\n

correct shape and vertical asymptote with correct equation for either graph       A1

\n

correct horizontal asymptote with correct equation for either graph       A1

\n

two completely correct sketches       A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

a ( 1 2 ) + 1 = 0 a = 2       A1

\n

from horizontal asymptote,  ( a b ) 2 = 4 9         (M1)

\n

a b = ± 2 3 b = ± 3        A1

\n

from vertical asymptote,  b ( 4 3 ) + c = 0

\n

b = 3,  c = −4 or  b = −3,  c = 4     A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.2.AHL.TZ0.H_8", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-8-reciprocal-and-simple-rational-functions-equations-of-asymptotes" ] }, { "Question": "
\n

Consider the polynomial \nq\n(\nx\n)\n=\n3\n\n\nx\n3\n\n\n\n11\n\n\nx\n2\n\n\n+\nk\nx\n+\n8\n.

\n
\n

Given that q ( x ) has a factor ( x 4 ) , find the value of k .

\n
[3]
\n
a.
\n
\n

Hence or otherwise, factorize \nq\n(\nx\n)\n as a product of linear factors.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

q ( 4 ) = 0     (M1)

\n

192 176 + 4 k + 8 = 0   ( 24 + 4 k = 0 )     A1

\n

k = 6     A1

\n

[3 marks]

\n
a.
\n
\n

\n3\n\n\nx\n3\n\n\n\n11\n\n\nx\n2\n\n\n\n6\nx\n+\n8\n=\n(\nx\n\n4\n)\n(\n3\n\n\nx\n2\n\n\n+\np\nx\n\n2\n)\n

\n

equate coefficients of \n\n\nx\n2\n\n\n:     (M1)

\n

\n\n12\n+\np\n=\n\n11\n

\n

\np\n=\n1\n

\n

\n(\nx\n\n4\n)\n(\n3\n\n\nx\n2\n\n\n+\nx\n\n2\n)\n     (A1)

\n

\n(\nx\n\n4\n)\n(\n3\nx\n\n2\n)\n(\nx\n+\n1\n)\n     A1

\n

 

\n

Note:     Allow part (b) marks if any of this work is seen in part (a).

\n

 

\n

Note:     Allow equivalent methods (eg, synthetic division) for the M marks in each part.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.AHL.TZ0.H_3", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

The following diagram shows the graph of y=-1-x+3 for x-3.

\n

\n
\n

A function f is defined by fx=-1-x+3 for x-3.

\n
\n

Describe a sequence of transformations that transforms the graph of y=x for x0 to the graph of y=-1-x+3 for x-3.

\n
[3]
\n
a.
\n
\n

State the range of f.

\n
[1]
\n
b.
\n
\n

Find an expression for f-1x, stating its domain.

\n
[5]
\n
c.
\n
\n

Find the coordinates of the point(s) where the graphs of y=fx and y=f-1x intersect.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

for example,

\n

a reflection in the x-axis (in the line y=0)        A1

\n

a horizontal translation (shift) 3 units to the left        A1

\n

a vertical translation (shift) down by 1 unit        A1

\n

 

\n

Note: Award A1 for each correct transformation applied in a correct position in the sequence. Do not accept use of the “move” for a translation.

\n

Note: Award A1A1A1 for a correct alternative sequence of transformations. For example,

\n

a vertical translation (shift) down by 1 unit, followed by a horizontal translation (shift) 3 units to the left and then a reflection in the line y=-1.

\n

 

\n

[3 marks]

\n
a.
\n
\n

range is fx-1        A1

\n

 

\n

Note: Correct alternative notations include ]-,-1](-,-1] or y-1.

\n

 

\n

[1 mark]

\n
b.
\n
\n

-1-y+3=x        M1

\n

 

\n

Note: Award M1 for interchanging x and y (can be done at a later stage).

\n

 

\n

y+3=-x-1=-x+1        A1

\n

y+3=x+12        A1

\n

so f-1x=x+12-3 f-1x=x2+2x-2        A1

\n

domain is x-1        A1

\n

 

\n

Note: Correct alternative notations include ]-,-1] or (-,-1].

\n

 

\n

[5 marks]

\n
c.
\n
\n

the point of intersection lies on the line y=x

\n

 

\n

EITHER

\n

x+12-3=x       M1   

\n

attempts to solve their quadratic equation       M1

\n

for example, x+2x-1=0 or x=-1±12-41-22  x=-1±32

\n

 

\n

OR

\n

-1-x+3=x       M1

\n

-1-x+32=x22x+3+x+4=x2

\n

substitutes 2x+3=-2x+1 to obtain -2x+1+x+4=x2

\n

attempts to solve their quadratic equation       M1

\n

for example, x+2x-1=0 or x=-1±12-41-22  x=-1±32

\n

 

\n

THEN

\n

x=-2,1        A1

\n

as x-1, the only solution is x=-2        R1

\n

so the coordinates of the point of intersection are -2,-2        A1

\n

 

\n

Note: Award R0A1 if -2,-2 is stated without a valid reason given for rejecting 1,1.

\n

 

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "EXN.1.SL.TZ0.8", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-11-transformation-of-functions", "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

The function f is defined by fx=3x+24x2-1, for xxpxq.

\n
\n

The graph of y=f(x) has exactly one point of inflexion.

\n
\n

The function g is defined by gx=4x2-13x+2, for x, x-23.

\n
\n

Find the value of p and the value of q.

\n
[2]
\n
a.
\n
\n

Find an expression for f'x.

\n
[3]
\n
b.
\n
\n

Find the x-coordinate of the point of inflexion.

\n
[2]
\n
c.
\n
\n

Sketch the graph of y=f(x) for -3x3, showing the values of any axes intercepts, the coordinates of any local maxima and local minima, and giving the equations of any asymptotes.

\n
[5]
\n
d.
\n
\n

Find the equations of all the asymptotes on the graph of y=g(x).

\n
[4]
\n
e.
\n
\n

By considering the graph of y=g(x)-f(x), or otherwise, solve f(x)<g(x) for x.

\n
[4]
\n
f.
\n
", "Markscheme": "
\n

attempt to solve 4x2-1=0 e.g. by factorising 4x2-1        (M1)

\n

p=12, q=-12 or vice versa        A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

attempt to use quotient rule or product rule        (M1)

\n

 

\n

EITHER

\n

f'x=34x2-1-8x3x+24x2-12=-12x2-16x-34x2-12        A1A1

\n

 

\n

Note: Award A1 for each term in the numerator with correct signs, provided correct denominator is seen.

\n

 

\n

OR

\n

f'x=-8x3x+24x2-1-2+34x2-1-1        A1A1

\n

 

\n

Note: Award A1 for each term.

\n

 

\n

[3 marks]

\n
b.
\n
\n

attempt to find the local min point on y=f'x OR solve f''x=0      (M1)

\n

x=-1.60     A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

      A1A1A1A1A1

\n

 

\n

Note: Award A1 for both vertical asymptotes with their equations, award A1 for horizontal asymptote with equation, award A1 for each correct branch including asymptotic behaviour, coordinates of minimum and maximum points (may be seen next to the graph) and values of axes intercepts.
If vertical asymptotes are absent (or not vertical) and the branches overlap as a consequence, award maximum A0A1A0A1A1.

\n

 

\n

[5 marks]

\n
d.
\n
\n

x=-23=-0.667         A1

\n

(oblique asymptote has) gradient 43=1.33         (A1)

\n

appropriate method to find complete equation of oblique asymptote         M1

\n

    3x+24x2+0x-1                      43x-89

\n

 4x2+83x-83x-1

\n

  -83x-16979

\n

y=43x-89=1.33x-0.889         A1

\n

Note: Do not award the final A1 if the answer is not given as an equation.

\n

 

\n

[4 marks]

\n
e.
\n
\n

attempting to find at least one critical value x=-0.568729, x=1.31872         (M1)

\n

-23<x<-0.569  OR  -0.5<x<0.5  OR  x>1.32        A1A1A1

\n

 

\n

Note: Only penalize once for use of  rather than <.

\n

 

\n

[4 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "21M.2.AHL.TZ1.11", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "ahl-2-13-rational-functions", "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

It is given that \nf\n(\nx\n)\n=\n3\n\n\nx\n4\n\n\n+\na\n\n\nx\n3\n\n\n+\nb\n\n\nx\n2\n\n\n\n7\nx\n\n4\n where \na\n and \nb\n are positive integers.

\n
\n

Given that \n\n\nx\n2\n\n\n\n1\n is a factor of \nf\n(\nx\n)\n find the value of \na\n and the value of \nb\n.

\n
[4]
\n
a.
\n
\n

Factorize \nf\n(\nx\n)\n into a product of linear factors.

\n
[3]
\n
b.
\n
\n

Using your graph state the range of values of \nc\n for which \nf\n(\nx\n)\n=\nc\n has exactly two distinct real roots.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ng\n(\nx\n)\n=\n3\n\n\nx\n4\n\n\n+\na\n\n\nx\n3\n\n\n+\nb\n\n\nx\n2\n\n\n\n7\nx\n\n4\n

\n

\ng\n(\n1\n)\n=\n0\n\na\n+\nb\n=\n8\n     M1A1

\n

\ng\n(\n\n1\n)\n=\n0\n\n\na\n+\nb\n=\n\n6\n     A1

\n

\n\na\n=\n7\n,\n\n \n\nb\n=\n1\n     A1

\n

[4 marks]

\n
a.
\n
\n

\n3\n\n\nx\n4\n\n\n+\n7\n\n\nx\n3\n\n\n+\n\n\nx\n2\n\n\n\n7\nx\n\n4\n=\n(\n\n\nx\n2\n\n\n\n1\n)\n(\np\n\n\nx\n2\n\n\n+\nq\nx\n+\nr\n)\n

\n

attempt to equate coefficients     (M1)

\n

\np\n=\n3\n,\n\n \n\nq\n=\n7\n,\n\n \n\nr\n=\n4\n     (A1)

\n

\n3\n\n\nx\n4\n\n\n+\n7\n\n\nx\n3\n\n\n+\n\n\nx\n2\n\n\n\n7\nx\n\n4\n=\n(\n\n\nx\n2\n\n\n\n1\n)\n(\n3\n\n\nx\n2\n\n\n+\n7\nx\n+\n4\n)\n

\n

\n=\n(\nx\n\n1\n)\n\n(\nx\n+\n1\n\n)\n2\n\n\n(\n3\nx\n+\n4\n)\n     A1

\n

 

\n

Note:     Accept any equivalent valid method.

\n

 

\n

[3 marks]

\n
b.
\n
\n

\nc\n>\n0\n     A1

\n

\n\n6.20\n<\nc\n<\n\n0.0366\n     A1A1

\n

 

\n

Note:     Award A1 for correct end points and A1 for correct inequalities.

\n

 

\n

Note:     If the candidate has misdrawn the graph and omitted the first minimum point, the maximum mark that may be awarded is A1FTA0A0 for \nc\n>\n\n6.20\n seen.

\n

 

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.2.AHL.TZ2.H_11", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

The following diagram shows a ball attached to the end of a spring, which is suspended from a ceiling.

\n

\n

The height, h metres, of the ball above the ground at time t seconds after being released can be modelled by the function ht=0.4cosπt+1.8 where t0.

\n
\n

Find the height of the ball above the ground when it is released.

\n
[2]
\n
a.
\n
\n

Find the minimum height of the ball above the ground.

\n
[2]
\n
b.
\n
\n

Show that the ball takes 2 seconds to return to its initial height above the ground for the first time.

\n
[2]
\n
c.
\n
\n

For the first 2 seconds of its motion, determine the amount of time that the ball is less than 1.8+0.22 metres above the ground.

\n
[5]
\n
d.
\n
\n

Find the rate of change of the ball’s height above the ground when t=13. Give your answer in the form pπqms-1 where p and q+.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

attempts to find h0       (M1)

\n

h0=0.4cos0+1.8=2.2

\n

2.2 (m) (above the ground)       A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

EITHER

\n

uses the minimum value of cosπt which is -1       M1

\n

0.4-1+1.8 (m)

\n

 

\n

OR

\n

the amplitude of motion is 0.4 (m) and the mean position is 1.8 (m)         M1

\n

 

\n

OR

\n

finds h't=-0.4πsinπt, attempts to solve h't=0 for t and determines that the minimum height above the ground occurs at t=1,3,        M1

\n

0.4-1+1.8 (m)

\n

 

\n

THEN

\n

1.4 (m) (above the ground)       A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

EITHER

\n

the ball is released from its maximum height and returns there a period later       R1

\n

the period is 2ππ=2 s       A1

\n

 

\n

OR

\n

attempts to solve ht=2.2 for t       M1

\n

cosπt=1

\n

t=0,2,       A1

\n

 

\n

THEN

\n

so it takes 2 seconds for the ball to return to its initial position for the first time       AG

\n

 

\n

[2 marks]

\n
c.
\n
\n

0.4cosπt+1.8=1.8+0.22       (M1)

\n

0.4cosπt=0.22

\n

cosπt=22       A1

\n

πt=π4,7π4       (A1)

\n

 

\n

Note: Accept extra correct positive solutions for πt.

\n

t=14,74 0t2       A1

\n

 

\n

Note: Do not award A1 if solutions outside 0t2 are also stated.

\n

the ball is less than 1.8+0.22 metres above the ground for 74-14(s)

\n

1.5(s)       A1

\n

  

\n

[5 marks]

\n
d.
\n
\n

EITHER

\n

attempts to find h't        (M1)

\n

 

\n

OR

\n

recognizes that h't is required        (M1)

\n

 

\n

THEN

\n

h't=-0.4πsinπt        A1

\n

attempts to evaluate their h'13        (M1)

\n

h'13=-0.4πsinπ3

\n

=0.2π3 ms-1        A1

\n

 

\n

Note: Accept equivalent correct answer forms where p. For example, -15π3.

\n

 

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "EXN.1.SL.TZ0.9", "topics": [ "topic-3-geometry-and-trigonometry", "topic-5-calculus" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations", "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

Let f(x) = x4 + px3 + qx + 5 where p, q are constants.

\n

The remainder when f(x) is divided by (x + 1) is 7, and the remainder when f(x) is divided by (x − 2) is 1. Find the value of p and the value of q.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to substitute x = −1 or x = 2 or to divide polynomials      (M1)

\n

1 − pq + 5 = 7, 16 + 8p + 2q + 5 = 1 or equivalent      A1A1

\n

attempt to solve their two equations M1

\n

p = −3, q = 2      A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ1.H_1", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

The function f has a derivative given by f'x=1xk-x, x, xo, xk where k is a positive constant.

\n
\n

Consider P, the population of a colony of ants, which has an initial value of 1200.

\n

The rate of change of the population can be modelled by the differential equation dPdt=Pk-P5k, where t is the time measured in days, t0, and k is the upper bound for the population.

\n
\n

At t=10 the population of the colony has doubled in size from its initial value.

\n
\n

The expression for f(x) can be written in the form ax+bk-x, where a, b. Find a and b in terms of k.

\n
[3]
\n
a.
\n
\n

Hence, find an expression for f(x).

\n
[3]
\n
b.
\n
\n

By solving the differential equation, show that P=1200kk-1200e-t5+1200.

\n
[8]
\n
c.
\n
\n

Find the value of k, giving your answer correct to four significant figures.

\n
[3]
\n
d.
\n
\n

Find the value of t when the rate of change of the population is at its maximum.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

1xk-xax+bk-x

\n

ak-x+bx=1         (A1)

\n

attempt to compare coefficients OR substitute x=k and x=0 and solve         (M1)

\n

a=1k and b=1k        A1

\n

f'(x)=1kx+1kk-x

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to integrate their ax+bk-x         (M1)

\n

fx1k1x+1k-xdx

\n

=1klnx-lnk-x+c=1klnxk-x+c         A1A1

\n

 

\n

Note: Award A1 for each correct term. Award A1A0 for a correct answer without modulus signs. Condone the absence of +c.

\n

 

\n

[3 marks]

\n
b.
\n
\n

attempt to separate variables and integrate both sides         M1

\n

5k1Pk-PdP=1dt

\n

5lnP-lnk-P=t+c         A1

\n

 

\n

Note: There are variations on this which should be accepted, such as 1klnP-lnk-P=15kt+c. Subsequent marks for these variations should be awarded as appropriate.

\n

 

\n

EITHER

\n

attempt to substitute t=0, P=1200 into an equation involving c        M1

\n

c=5ln1200-lnk-1200=5ln1200k-1200         A1

\n

5lnP-lnk-P=t+5ln1200-lnk-1200         A1

\n

lnPk-12001200k-P=t5

\n

Pk-12001200k-P=et5         A1

\n

 

\n

OR

\n

lnPk-P=t+c5

\n

Pk-P=Aet5         A1

\n

attempt to substitute t=0, P=1200        M1

\n

1200k-1200=A         A1

\n

Pk-P=1200et5k-1200         A1

\n

 

\n

THEN

\n

attempt to rearrange and isolate P        M1

\n

Pk-1200P=1200ket5-1200Pet5  OR  Pke-t5-1200Pe-t5 =1200k-1200P  OR  kP-1=k-12001200et5

\n

Pk-1200+1200et5=1200ket5  OR  Pke-t5-1200e-t5+1200=1200k         A1

\n

 

\n

P=1200kk-1200e-t5+1200         AG

\n

 

\n

[8 marks]

\n
c.
\n
\n

attempt to substitute t=10, P=2400         (M1)

\n

2400=1200kk-1200e-2+1200          (A1)

\n

k=2845.34

\n

k=2845          A1

\n

 

\n

Note: Award (M1)(A1)A0 for any other value of k which rounds to 2850

\n

 

\n

[3 marks]

\n
d.
\n
\n

attempt to find the maximum of the first derivative graph OR zero of the second derivative graph OR that P=k2=1422.67         (M1)

\n

t=1.57814

\n

=1.58 (days)         A2

\n

 

\n

Note: Accept any value which rounds to 1.6.

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.2.AHL.TZ1.12", "topics": [ "topic-1-number-and-algebra", "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "ahl-1-11-partial-fractions", "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx", "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

The following diagram shows part of the graph of \n2\n\n\nx\n2\n\n\n=\n\nsi\n\n\n\n\nn\n\n3\n\n\n\ny\n for \n0\n\ny\n\nπ\n.

\n

\n
\n

The shaded region \nR\n is the area bounded by the curve, the \ny\n-axis and the lines \ny\n=\n0\n and \ny\n=\nπ\n.

\n
\n

Using implicit differentiation, find an expression for d y d x .

\n
[4]
\n
a.i.
\n
\n

Find the equation of the tangent to the curve at the point  ( 1 4 5 π 6 ) .

\n
[4]
\n
a.ii.
\n
\n

Find the area of R .

\n
[3]
\n
b.
\n
\n

The region R is now rotated about the y -axis, through 2 π radians, to form a solid.

\n

By writing  si n 3 y as  ( 1 co s 2 y ) sin y , show that the volume of the solid formed is 2 π 3 .

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

valid attempt to differentiate implicitly       (M1)

\n

4 x = 3 si n 2 y cos y d y d x        A1A1

\n

d y d x = 4 x 3 si n 2 y cos y        A1

\n

[4 marks]

\n
a.i.
\n
\n

at  ( 1 4 5 π 6 ) d y d x = 4 x 3 si n 2 y cos y = 1 3 ( 1 2 ) 2 ( 3 2 )        (M1)

\n

d y d x = 8 3 3 ( = 1.54 )        A1

\n

hence equation of tangent is

\n

y 5 π 6 = 1.54 ( x 1 4 )   OR   y = 1.54 x + 3.00        (M1)A1

\n

Note: Accept  y = 1.54 x + 3

\n

[4 marks]

\n
a.ii.
\n
\n

x = 1 2 si n 3 y        (M1)

\n

0 π 1 2 si n 3 y d y        (A1)

\n

= 1.24        A1

\n

[3 marks]

\n
b.
\n
\n

use of volume  = π x 2 d y        (M1)

\n

= 0 π 1 2 π si n 3 y d y        A1

\n

= 1 2 π 0 π ( sin y sin y co s 2 y ) d y

\n

Note: Condone absence of limits up to this point.

\n

reasonable attempt to integrate       (M1)

\n

= 1 2 π [ cos y + 1 3 co s 3 y ] 0 π        A1A1

\n

Note: Award A1 for correct limits (not to be awarded if previous M1 has not been awarded) and A1 for correct integrand.

\n

= 1 2 π ( 1 1 3 ) 1 2 π ( 1 + 1 3 )  A1

\n

= 2 π 3        AG

\n

Note: Do not accept decimal answer equivalent to  2 π 3 .

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.2.AHL.TZ0.H_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal", "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Consider the polynomial \nP\n\n(\nz\n)\n\n\n\n\nz\n4\n\n\n\n6\n\n\nz\n3\n\n\n\n2\n\n\nz\n2\n\n\n+\n58\nz\n\n51\n,\n\n\nz\n\n\nC\n\n.

\n
\n

Sketch the graph of y = x 4 6 x 3 2 x 2 + 58 x 51 , stating clearly the coordinates of any maximum and minimum points and intersections with axes.

\n
[6]
\n
b.
\n
\n

Hence, or otherwise, state the condition on k R such that all roots of the equation P ( z ) = k are real.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

\n

shape       A1

\n

x -axis intercepts at (−3, 0), (1, 0) and y -axis intercept at (0, −51)       A1A1

\n

minimum points at (−1.62, −118) and (3.72, 19.7)       A1A1

\n

maximum point at (2.40, 26.9)       A1

\n

Note: Coordinates may be seen on the graph or elsewhere.

\n

Note: Accept −3, 1 and −51 marked on the axes.

\n

[6 marks]

\n
b.
\n
\n

from graph, 19.7 ≤ k  ≤ 26.9       A1A1

\n

Note: Award A1 for correct endpoints and A1 for correct inequalities.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.AHL.TZ2.H_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

The following diagram shows the graph of \ny\n=\nf\n\n(\nx\n)\n\n\n\n3\n\nx\n\n5\n.

\n

\n
\n

Find the value of ( f f ) ( 1 ) .

\n
[2]
\n
a.
\n
\n

Given that  f 1 ( a ) = 3 , determine the value of a .

\n
[2]
\n
b.
\n
\n

Given that g ( x ) = 2 f ( x 1 ) , find the domain and range of g .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

f ( 1 ) = 0        (A1)

\n

f ( 0 ) = 1         A1

\n

[2 marks]

\n
a.
\n
\n

a = f ( 3 )       (M1)

\n

a = 4        A1

\n

[2 marks]

\n
b.
\n
\n

domain is  2 x 6        A1

\n

range is  6 y 10        A1

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.2.AHL.TZ0.H_3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Consider the function \nq\n\n(\nx\n)\n\n=\n\n\nx\n5\n\n\n\n10\n\n\nx\n2\n\n\n+\n15\nx\n\n6\n,\n\n \n\nx\n\n\nR\n\n.

\n
\n

Show that the graph of y = q ( x ) is concave up for x > 1 .

\n
[3]
\n
e.i.
\n
\n

Sketch the graph of y = q ( x ) showing clearly any intercepts with the axes.

\n
[3]
\n
e.ii.
\n
", "Markscheme": "
\n

d 2 y d x 2 = 20 x 3 20      M1A1

\n

for x > 1 ,   20 x 3 20 > 0 concave up     R1AG

\n

 

\n

[3 marks]

\n
e.i.
\n
\n

\"M17/5/MATHL/HP1/ENG/TZ1/B12.e.ii/M\"

\n

x -intercept at ( 1 ,   0 )      A1

\n

y -intercept at ( 0 ,   6 )      A1

\n

stationary point of inflexion at ( 1 ,   0 ) with correct curvature either side     A1

\n

[3 marks]

\n
e.ii.
\n
", "Examiners report": "
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
", "question_id": "17M.1.AHL.TZ1.H_12", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-7-the-second-derivative" ] }, { "Question": "
\n

Use l’Hôpital’s rule to determine the value of limx02xcosx25tanx.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

 attempts to apply l’Hôpital’s rule on limx02xcosx25tanx        M1

\n

=limx02cosx2-4x2sinx25sec2x        M1A1A1

\n

 

\n

Note: Award M1 for attempting to use product and chain rule differentiation on the numerator, A1 for a correct numerator and A1 for a correct denominator. The awarding of A1 for the denominator is independent of the M1.

\n

=25        A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.1.AHL.TZ0.6", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Consider quadrilateral PQRS where PQ is parallel to SR.

\n

\n

In PQRS, PQ=x, SR=y, RS^P=α and QR^S=β.

\n

Find an expression for PS in terms of x,y,sinβ and sinα+β.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

METHOD 1

\n

from vertex P, draws a line parallel to QR that meets SR at a point X        (M1)

\n

uses the sine rule in ΔPSX        M1

\n

PSsinβ=y-xsin180°-α-β        A1

\n

sin180°-α-β=sinα+β        (A1)

\n

PS=y-xsinβsinα+β        A1

\n

 

\n

METHOD 2

\n

let the height of quadrilateral PQRS be h

\n

h=PSsinα        A1

\n

attempts to find a second expression for h        M1

\n

h=y-x-PScosαtanβ

\n

PSsinα=y-x-PScosαtanβ

\n

writes tanβ as sinβcosβ, multiplies through by cosβ and expands the RHS        M1

\n

PSsinαcosβ=y-xsinβ-PScosαsinβ

\n

PS=y-xsinβsinαcosβ+cosαsinβ        A1

\n

PS=y-xsinβsinα+β        A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.1.AHL.TZ0.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The polynomial \n\n\nx\n4\n\n\n+\np\n\n\nx\n3\n\n\n+\nq\n\n\nx\n2\n\n\n+\nr\nx\n+\n6\n is exactly divisible by each of \n\n(\n\nx\n\n1\n\n)\n\n\n\n(\n\nx\n\n2\n\n)\n\n and \n\n(\n\nx\n\n3\n\n)\n\n.

\n

Find the values of \np\n\nq\n and \nr\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

substitute each of \nx\n = 1,2 and 3 into the quartic and equate to zero      (M1)

\n

\np\n+\nq\n+\nr\n=\n\n7\n

\n

\n4\np\n+\n2\nq\n+\nr\n=\n\n11\n or equivalent        (A2)

\n

\n9\np\n+\n3\nq\n+\nr\n=\n\n29\n

\n

Note: Award A2 for all three equations correct, A1 for two correct.

\n

attempting to solve the system of equations      (M1)

\n

\np\n = −7, \nq\n = 17, \nr\n = −17     A1

\n

Note: Only award M1 when some numerical values are found when solving algebraically or using GDC.

\n

 

\n

METHOD 2

\n

attempt to find fourth factor      (M1)

\n

\n\n(\n\nx\n\n1\n\n)\n\n     A1

\n

attempt to expand \n\n\n\n(\n\nx\n\n1\n\n)\n\n2\n\n\n\n(\n\nx\n\n2\n\n)\n\n\n(\n\nx\n\n3\n\n)\n\n     M1

\n

\n\n\nx\n4\n\n\n\n7\n\n\nx\n3\n\n\n+\n17\n\n\nx\n2\n\n\n\n17\nx\n+\n6\n (\np\n = −7, \nq\n = 17, \nr\n = −17)     A2

\n

Note: Award A2 for all three values correct, A1 for two correct.

\n

Note: Accept long / synthetic division.

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.AHL.TZ2.H_2", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

This question asks you to explore the behaviour and key features of cubic polynomials of the form x3-3cx+d.

\n

 

\n

Consider the function fx=x3-3cx+2 for x and where c is a parameter, c.

\n

The graphs of y=f(x) for c=-1 and c=0 are shown in the following diagrams.

\n


                                                                    c=-1                                                                               c=0

\n

\n
\n

On separate axes, sketch the graph of y=f(x) showing the value of the y-intercept and the coordinates of any points with zero gradient, for

\n
\n

Hence, or otherwise, find the set of values of c such that the graph of y=f(x) has

\n
\n

Given that the graph of y=f(x) has one local maximum point and one local minimum point, show that

\n
\n

Hence, for c>0, find the set of values of c such that the graph of y=f(x) has

\n
\n

c=1.

\n
[3]
\n
a.i.
\n
\n

c=2.

\n
[3]
\n
a.ii.
\n
\n

Write down an expression for f'(x).

\n
[1]
\n
b.
\n
\n

a point of inflexion with zero gradient.

\n
[1]
\n
c.i.
\n
\n

one local maximum point and one local minimum point.

\n
[2]
\n
c.ii.
\n
\n

no points where the gradient is equal to zero.

\n
[1]
\n
c.iii.
\n
\n

the y-coordinate of the local maximum point is 2c32+2.

\n
[3]
\n
d.i.
\n
\n

the y-coordinate of the local minimum point is -2c32+2.

\n
[1]
\n
d.ii.
\n
\n

exactly one x-axis intercept.

\n
[2]
\n
e.i.
\n
\n

exactly two x-axis intercepts.

\n
[2]
\n
e.ii.
\n
\n

exactly three x-axis intercepts.

\n
[2]
\n
e.iii.
\n
\n

Consider the function g(x)=x3-3cx+d for x and where c , d.

\n

Find all conditions on c and d such that the graph of y=g(x) has exactly one x-axis intercept, explaining your reasoning.

\n
[6]
\n
f.
\n
", "Markscheme": "
\n

\n

c=1: positive cubic with correct y-intercept labelled          A1

\n

local maximum point correctly labelled          A1

\n

local minimum point correctly labelled          A1

\n

 

\n

[3 marks]

\n
a.i.
\n
\n

\n

c=2: positive cubic with correct y-intercept labelled          A1

\n

local maximum point correctly labelled          A1

\n

local minimum point correctly labelled          A1

\n

 

\n

Note: Accept the following exact answers:
          Local maximum point coordinates -2,2+42.
          Local minimum point coordinates 2,2-42.

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

f'(x) =3x2-3c       A1

\n

 

\n

Note: Accept 3x2-3c (an expression).

\n

 

\n

[1 mark]

\n
b.
\n
\n

c=0       A1

\n

 

\n

[1 mark]

\n
c.i.
\n
\n

considers the number of solutions to their f'(x)=0         (M1)

\n

3x2-3c=0

\n

c>0          A1

\n

 

\n

[2 marks]

\n
c.ii.
\n
\n

c<0          A1

\n

 

\n

Note: The (M1) in part (c)(ii) can be awarded for work shown in either (ii) or (iii). 

\n

 

\n

[1 mark]

\n
c.iii.
\n
\n

attempts to solve their f'(x)=0 for x        (M1)

\n

x±c        (A1)

\n

 

\n

Note: Award (A1) if either x=-c or x=c is subsequently considered.
          Award the above (M1)(A1) if this work is seen in part (c).

\n

 

\n

correctly evaluates f-c        A1  

\n

f-c=-c32+3c32+2 =-cc+3cc+2

\n

the y-coordinate of the local maximum point is 2c32+2        AG

\n

 

\n

[3 marks]

\n
d.i.
\n
\n

 

\n

correctly evaluates fc        A1  

\n

fc=c32-3c32+2 =cc-3cc+2

\n

the y-coordinate of the local minimum point is -2c32+2        AG

\n

 

\n

[1 mark]

\n
d.ii.
\n
\n

the graph of y=fx will have one x-axis intercept if

\n

EITHER

\n

-2c32+2>0 (or equivalent reasoning)         R1

\n

 

\n

OR

\n

the minimum point is above the x-axis         R1

\n

 

\n

Note: Award R1 for a rigorous approach that does not (only) refer to sketched graphs.

\n

 

\n

THEN

\n

0<c<1        A1  

\n

 

\n

Note: Condone c<1. The A1 is independent of the R1.

\n

 

\n

[2 marks]

\n
e.i.
\n
\n

the graph of y=fx will have two x-axis intercepts if

\n

EITHER

\n

-2c32+2=0 (or equivalent reasoning)         (M1)

\n

 

\n

OR

\n

evidence from the graph in part(a)(i)         (M1)

\n

 

\n

THEN

\n

c=1        A1  

\n

  

\n

[2 marks]

\n
e.ii.
\n
\n

the graph of y=fx will have three x-axis intercepts if

\n

EITHER

\n

-2c32+2<0 (or equivalent reasoning)         (M1)

\n

 

\n

OR

\n

reasoning from the results in both parts (e)(i) and (e)(ii)       (M1)

\n

 

\n

THEN

\n

c>1        A1  

\n

  

\n

[2 marks]

\n
e.iii.
\n
\n

case 1:

\n

c0 (independent of the value of d)        A1 

\n

EITHER

\n

g'(x)=0 does not have two solutions (has no solutions or 1 solution)                   R1

\n


OR

\n

g'x0  for  x~                   R1

\n


OR

\n

the graph of y=fx has no local maximum or local minimum points, hence any vertical translation of this graph (y=gx) will also have no local maximum or local minimum points                   R1

\n


THEN

\n

therefore there is only one x-axis intercept        AG

\n

 

\n

Note: Award at most A0R1 if only c<0 is considered.

\n

 

\n


case 2

\n

c>0

\n

-c,2c32+d is a local maximum point and c,-2c32+d is a local minimum point              (A1)

\n

 

\n

Note: Award (A1) for a correct y-coordinate seen for either the maximum or the minimum.

\n

 

\n

considers the positions of the local maximum point and/or the local minimum point              (M1)

\n

 

\n

EITHER
considers both points above the x-axis or both points below the x-axis


OR

\n

considers either the local minimum point only above the x-axis OR the local maximum point only below the x-axis


THEN

\n

d>2c32 (both points above the x-axis)        A1 

\n

d<-2c32 (both points above the x-axis)        A1 

\n

 

\n

Note: Award at most (A1)(M1)A0A0 for case 2 if c>0 is not clearly stated.

\n

 

\n

[6 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
e.iii.
\n
\n[N/A]\n
f.
\n
", "question_id": "21M.3.AHL.TZ1.1", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-3-graphing", "sl-5-3-differentiating-polynomials-n-e-z", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion", "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

The lines l1 and l2 have the following vector equations where λ,μ and m.

\n

l1:r1=3-20+λ21m l2:r2=-1-4-2m+μ2-5-m

\n
\n

The plane Π has Cartesian equation x+4y-z=p where p.

\n

 

\n

Given that l1 and Π have no points in common, find

\n
\n

Show that l1 and l2 are never perpendicular to each other.

\n
[3]
\n
a.
\n
\n

the value of m.

\n
[2]
\n
b.i.
\n
\n

the condition on the value of p.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

attempts to calculate 21m·2-5-m        (M1)

\n

=-1-m2        A1

\n

since m20, -1-m2<0 for m         R1

\n

so l1 and l2 are never perpendicular to each other        AG

\n

 

\n

[3 marks]

\n
a.
\n
\n

(since l1 is parallel to Π, l1 is perpendicular to the normal of Π and so)

\n

21m·14-1=0         R1

\n

2+4-m=0

\n

m=6        A1

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

since there are no points in common, 3,-2,0 does not lie in Π       

\n

 

\n

EITHER

\n

substitutes 3,-2,0 into x+4y-zp        (M1)

\n

 

\n

OR

\n

3-20·14-1p        (M1)

\n

 

\n

THEN

\n

p-5        A1

\n

 

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "EXN.1.AHL.TZ0.8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product", "ahl-3-17-vector-equations-of-a-plane" ] }, { "Question": "
\n

Let \nP\n\n(\nx\n)\n\n=\n2\n\n\nx\n4\n\n\n\n15\n\n\nx\n3\n\n\n+\na\n\n\nx\n2\n\n\n+\nb\nx\n+\nc\n, where \na\n\nb\n\nc\n\n\nR\n\n

\n
\n

Given that \n\n(\n\nx\n\n5\n\n)\n\n is a factor of \nP\n\n(\nx\n)\n\n, find a relationship between \na\n, \nb\n and \nc\n.

\n
[2]
\n
a.
\n
\n

Given that \n\n\n\n(\n\nx\n\n5\n\n)\n\n2\n\n\n is a factor of \nP\n\n(\nx\n)\n\n, write down the value of \n\nP\n\n\n\n(\n5\n)\n\n.

\n
[1]
\n
b.
\n
\n

Given that \n\n\n\n(\n\nx\n\n5\n\n)\n\n2\n\n\n is a factor of \nP\n\n(\nx\n)\n\n, and that \na\n=\n2\n, find the values of \nb\n and \nc\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to substitute \nx\n=\n5\n and set equal to zero, or use of long / synthetic division      (M1)

\n

\n2\n×\n\n\n5\n4\n\n\n\n15\n×\n\n\n5\n3\n\n\n+\na\n×\n\n\n5\n2\n\n\n+\n5\nb\n+\nc\n=\n0\n      A1

\n

\n\n(\n\n\n25\na\n+\n5\nb\n+\nc\n=\n625\n\n)\n\n

\n

 

\n

[2 marks]

\n
a.
\n
\n

0     A1

\n

 

\n

[1 mark]

\n
b.
\n
\n

EITHER

\n

attempt to solve \n\nP\n\n\n\n(\n5\n)\n\n=\n0\n     (M1)

\n

\n\n8\n×\n\n\n5\n3\n\n\n\n45\n×\n\n\n5\n2\n\n\n+\n4\n×\n5\n+\nb\n=\n0\n

\n

 

\n

OR

\n

\n\n(\n\n\n\nx\n2\n\n\n\n10\nx\n+\n25\n\n)\n\n\n(\n\n2\n\n\nx\n2\n\n\n+\nα\nx\n+\nβ\n\n)\n\n=\n2\n\n\nx\n4\n\n\n\n15\n\n\nx\n3\n\n\n+\n2\n\n\nx\n2\n\n\n+\nb\nx\n+\nc\n      (M1)

\n

comparing coefficients gives \nα\n = 5, \nβ\n = 2

\n

 

\n

THEN

\n

\nb\n = 105      A1

\n

\n\nc\n=\n625\n\n25\n×\n2\n\n525\n

\n

\nc\n = 50      A1

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.2.AHL.TZ0.H_6", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

The following shape consists of three arcs of a circle, each with centre at the opposite vertex of an equilateral triangle as shown in the diagram.

\n

\n

For this shape, calculate

\n
\n

the perimeter.

\n
[2]
\n
a.
\n
\n

the area.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

each arc has length  r θ = 6 × π 3 = 2 π ( = 6.283 )        (M1)

\n

perimeter is therefore  6 π ( = 18.8 ) (cm)        A1

\n

[2 marks]

\n
a.
\n
\n

area of sector, s , is  1 2 r 2 θ = 18 × π 3 = 6 π ( = 18.84 )        (A1)

\n

area of triangle, t , is  1 2 × 6 × 3 3 = 9 3 ( = 15.58 )        (M1)(A1)

\n

Note: area of segment, k , is 3.261… implies area of triangle

\n

finding  3 s 2 t or  3 k + t or similar

\n

area  = 3 s 2 t = 18 π 18 3 ( = 25.4 )  (cm2)       (M1)A1

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.2.AHL.TZ0.H_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

It is given that 2cosAsinBsinA+B-sinA-B. (Do not prove this identity.)

\n

Using mathematical induction and the above identity, prove that Σr=1ncos2r-1θ=sin2nθ2sinθ for n+.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

let Pn be the proposition that Σr=1ncos2r-1θ=sin2nθ2sinθ for n+

\n

considering P1:

\n

LHS=cos1θ=cosθ and RHS=sin2θ2sinθ=2sinθcosθ2sinθ=cosθ=LHS

\n

so P1 is true        R1

\n

assume Pk is true, i.e. Σr=1kcos2r-1θ=sin2kθ2sinθ k+        M1

\n

 

\n

Note: Award M0 for statements such as “let n=k”.

\n

Note: Subsequent marks after this M1 are independent of this mark and can be awarded.

\n

 

\n

considering Pk+1

\n

Σr=1k+1cos2r-1θ=Σr=1kcos2r-1θ+cos2k+1-1θ        M1

\n

=sin2kθ2sinθ +cos2k+1-1θ        A1

\n

=sin2kθ+2cos2k+1θsinθ2sinθ 

\n

=sin2kθ+sin2k+1θ+θ-sin2k+1θ-θ2sinθ         M1

\n

 

\n

Note: Award M1 for use of 2cosAsinB=sinA+B-sinA-B with A=2k+1θ and B=θ.

\n

 

\n

=sin2kθ+sin2k+2θ-sin2kθ2sinθ         A1

\n

=sin2k+1θ2sinθ         A1

\n

Pk+1 is true whenever Pk is true, P1 is true, so Pn is true for n+        R1

\n

 

\n

Note: Award the final R1 mark provided at least five of the previous marks have been awarded.

\n

 

\n

[8 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.1.AHL.TZ0.9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

A function f is defined by fx=3x2+2, x.

\n
\n

The region R is bounded by the curve y=fx, the x-axis and the lines x=0 and x=6. Let A be the area of R.

\n
\n

The line x=k divides R into two regions of equal area.

\n
\n

Let m be the gradient of a tangent to the curve y=fx.

\n
\n

Sketch the curve y=fx, clearly indicating any asymptotes with their equations and stating the coordinates of any points of intersection with the axes.

\n
[4]
\n
a.
\n
\n

Show that A=2π2.

\n
[4]
\n
b.
\n
\n

Find the value of k.

\n
[4]
\n
c.
\n
\n

Show that m=-6xx2+22.

\n
[2]
\n
d.
\n
\n

Show that the maximum value of m is 273223.

\n
[7]
\n
e.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

\n

a curve symmetrical about the y-axis with correct concavity that has a local maximum point on the positive y-axis        A1

\n

a curve clearly showing that y0 as x±        A1

\n

0,32        A1

\n

horizontal asymptote y=0 (x-axis)        A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

attempts to find 3x2+2dx        (M1)

\n

=32arctanx2        A1

\n

 

\n

Note: Award M1A0 for obtaining k arctanx2 where k32.

\n

Note: Condone the absence of or use of incorrect limits to this stage.

\n

 

\n

=32arctan3-arctan0        (M1)

\n

=32×π3=π2        A1

\n

A=2π2        AG

\n

 

\n

[4 marks]

\n
b.
\n
\n

METHOD 1

\n

EITHER

\n

0k3x2+2dx=2π4

\n

32arctank2=2π4        (M1)

\n

 

\n

OR

\n

k63x2+2dx=2π4

\n

32arctan3-arctank2=2π4        (M1)

\n

arctan3-arctank2=π6

\n

 

\n

THEN

\n

arctank2=π6        A1

\n

k2=tanπ6=13        A1

\n

k=63=23        A1

\n

 

\n

METHOD 2

\n

0k3x2+2dx=k63x2+2dx

\n

32arctank2=32arctan3-arctank2        (M1)

\n

arctank2=π6        A1

\n

k2=tanπ6=13        A1

\n

k=63=23        A1

\n

 

\n

[4 marks]

\n
c.
\n
\n

attempts to find ddx3x2+2        (M1)

\n

=3-12xx2+2-2        A1

\n

so m=-6xx2+22        AG

\n

 

\n

[2 marks]

\n
d.
\n
\n

attempts product rule or quotient rule differentiation        M1

\n

EITHER

\n

dmdx=-6x-22xx2+2-3+x2+2-2-6        A1

\n

OR

\n

dmdx=x2+22-6--6x22xx2+2x2+24        A1

\n

 

\n

Note: Award A0 if the denominator is incorrect. Subsequent marks can be awarded.

\n

 

\n

THEN

\n

attempts to express their dmdx as a rational fraction with a factorized numerator        M1

\n

dmdx=6x2+23x2-2x2+24=63x2-2x2+23

\n

attempts to solve their dmdx=0 for x        M1

\n

x=±23        A1

\n

from the curve, the maximum value of m occurs at x=-23        R1

\n

(the minimum value of m occurs at x=23)

\n

 

\n

Note: Award R1 for any equivalent valid reasoning.

\n

 

\n

maximum value of m is -6-23-232+22        A1

\n

leading to a maximum value of 273223        AG

\n

 

\n

[7 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "EXN.1.AHL.TZ0.11", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology", "ahl-5-15-further-derivatives-and-indefinite-integration-of-these-partial-fractions", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Consider the expansion of  ( 2 + x ) n , where  n 3 and  n Z .

\n

The coefficient of  x 3  is four times the coefficient of  x 2 . Find the value of n .

\n
", "Markscheme": "
\n

attempt to find coefficients in binomial expansion       (M1)

\n

coefficient of  x 2 : ( n 2 ) × 2 n 2 ; coefficient of  x 3 : ( n 3 ) × 2 n 3          A1A1

\n

Note: Condone terms given rather than coefficients. Terms may be seen in an equation such as that below.

\n

( n 3 ) × 2 n 3 = 4 ( n 2 ) × 2 n 2        (A1)

\n

attempt to solve equation using GDC or algebraically       (M1)

\n

( n 3 ) = 8 ( n 2 )

\n

n ! 3 ! ( n 3 ) ! = 8 n ! 2 ! ( n 2 ) !

\n

1 3 = 8 n 2

\n

n = 26        A1

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.2.AHL.TZ0.H_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Consider the equation z 4 + a z 3 + b z 2 + c z + d = 0 , where  a b c , d R and  z C .

\n

Two of the roots of the equation are log26 and i 3 and the sum of all the roots is 3 + log23.

\n

Show that 6 a + d + 12 = 0.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

i 3  is a root      (A1)

\n

3 + lo g 2 3 lo g 2 6 ( = 3 + lo g 2 1 2 = 3 1 = 2 ) is a root       (A1)

\n

sum of roots:  a = 3 + lo g 2 3 a = 3 lo g 2 3      M1

\n

Note: Award M1 for use of a is equal to the sum of the roots, do not award if minus is missing.

\n

Note: If expanding the factored form of the equation, award M1 for equating a to the coefficient of z 3 .

\n

 

\n

product of roots:  ( 1 ) 4 d           = 2 ( lo g 2 6 ) ( i 3 ) ( i 3 )       M1

\n

                                                    = 6 lo g 2 6       A1

\n

Note: Award M1A0 for  d = 6 lo g 2 6

\n

 

\n

6 a + d + 12 = 18 6 lo g 2 3 + 6 lo g 2 6 + 12

\n

 

\n

EITHER

\n

= 6 + 6 lo g 2 2 = 0       M1A1AG

\n

Note: M1 is for a correct use of one of the log laws.

\n

OR

\n

= 6 6 lo g 2 3 + 6 lo g 2 3 + 6 lo g 2 2 = 0        M1A1AG

\n

Note: M1 is for a correct use of one of the log laws.

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.1.AHL.TZ0.H_8", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

The random variable X follows a normal distribution with mean μ and standard deviation σ.

\n
\n

The avocados grown on a farm have weights, in grams, that are normally distributed with mean μ and standard deviation σ. Avocados are categorized as small, medium, large or premium, according to their weight. The following table shows the probability an avocado grown on the farm is classified as small, medium, large or premium.

\n

\n

The maximum weight of a small avocado is 106.2 grams.

\n

The minimum weight of a premium avocado is 182.6 grams.

\n
\n

A supermarket purchases all the avocados from the farm that weigh more than 106.2 grams.

\n
\n

Find the probability that an avocado chosen at random from this purchase is categorized as

\n
\n

Find Pμ-1.5σ<X<μ+1.5σ.

\n
[3]
\n
a.
\n
\n

Find the value of μ and of σ.

\n
[5]
\n
b.
\n
\n

medium.

\n
[2]
\n
c.i.
\n
\n

large.

\n
[1]
\n
c.ii.
\n
\n

premium.

\n
[1]
\n
c.iii.
\n
\n

The selling prices of the different categories of avocado at this supermarket are shown in the following table:

\n

\n

 

\n

 

\n

 

\n

 

\n

The supermarket pays the farm $200 for the avocados and assumes it will then sell them in exactly the same proportion as purchased from the farm.

\n

According to this model, find the minimum number of avocados that must be sold so that the net profit for the supermarket is at least $438.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

Pμ-1.5σ-μσ<X-μσ<μ+1.5σ-μσ                (M1)

\n

P-1.5<Z<1.5  OR  1-2×PZ<-1.5                (A1)

\n

P-1.5<Z<1.5=0.866385

\n

Pμ-1.5σ<X<μ+1.5σ=0.866                A1

\n


Note: Do not award any marks for use of their answers from part (b).

\n

 

\n

[3 marks]

\n
a.
\n
\n

z1=-1.75068  and  z2=1.30468 (seen anywhere)                (A1)

\n

correct equations                (A1)(A1)

\n

106.2-μσ=-1.75068,  μ+1.30468σ=182.6

\n

attempt to solve their equations involving z values                (M1)

\n

μ=149.976..., σ=25.0051

\n

μ=150, σ=25.0                A1

\n

 

\n

[5 marks]

\n
b.
\n
\n

new sample space is 96% (may be seen in (ii) or (iii))                (M1)

\n

Pmedium|not small  OR  0.5760.96

\n

PMedium=0.6                A1

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

PLarge=0.3                A1

\n

 

\n

[1 mark]

\n
c.ii.
\n
\n

PPremium=0.1                A1

\n

 

\n

[1 mark]

\n
c.iii.
\n
\n

attempt to express revenue from avocados                (M1)

\n

1.1×0.6+1.29×0.3+1.96×0.1  OR  1.243n

\n

correct inequality or equation for net profit in terms of n                (A1)

\n

1.1×0.6n+1.29×0.3n+1.96×0.1n-200438  OR  1.243n-200=438

\n

attempt to solve the inequality                (M1)

\n

sketch  OR  n=513.274...

\n

n=514                A1

\n


Note:
Only award follow through in part (d) for 3 probabilities which add up to 1. FT of probabilities from c) that do not add up to 1 should only be awarded M marks, where appropriate, in d).

\n

 

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
\n[N/A]\n
d.
\n
", "question_id": "21N.2.SL.TZ0.9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The quadratic equation \n\n\nx\n2\n\n\n\n2\nk\nx\n+\n(\nk\n\n1\n)\n=\n0\n has roots \nα\n and \nβ\n such that \n\n\nα\n2\n\n\n+\n\n\nβ\n2\n\n\n=\n4\n. Without solving the equation, find the possible values of the real number \nk\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nα\n+\nβ\n=\n2\nk\n    A1

\n

\nα\nβ\n=\nk\n\n1\n    A1

\n

\n\n(\nα\n+\nβ\n\n)\n2\n\n\n=\n4\n\n\nk\n2\n\n\n\n\n\nα\n2\n\n\n+\n\n\nβ\n2\n\n\n+\n2\n\n\n\n\nα\nβ\n\n\n\n\n\nk\n\n1\n\n\n=\n4\n\n\nk\n2\n\n\n    (M1)

\n

\n\n\nα\n2\n\n\n+\n\n\nβ\n2\n\n\n=\n4\n\n\nk\n2\n\n\n\n2\nk\n+\n2\n

\n

\n\n\nα\n2\n\n\n+\n\n\nβ\n2\n\n\n=\n4\n\n4\n\n\nk\n2\n\n\n\n2\nk\n\n2\n=\n0\n    A1

\n

attempt to solve quadratic     (M1)

\n

\nk\n=\n1\n,\n\n \n\n\n\n1\n2\n\n    A1

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.1.AHL.TZ0.H_5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

Let P ( z ) = a z 3 37 z 2 + 66 z 10 , where  z C and  a Z .

\n

One of the roots of  P ( z ) = 0 is  3 + i . Find the value of a .

\n
", "Markscheme": "
\n

METHOD 1

\n

one other root is  3 i          A1

\n

let third root be  α        (M1)

\n

considering sum or product of roots       (M1)

\n

sum of roots  = 6 + α = 37 a          A1

\n

product of roots  = 10 α = 10 a          A1

\n

hence  a = 6          A1

\n

 

\n

METHOD 2

\n

one other root is  3 i          A1

\n

quadratic factor will be  z 2 6 z + 10        (M1)A1

\n

P ( z ) = a z 3 37 z 2 + 66 z 10 = ( z 2 6 z + 10 ) ( a z 1 )        M1

\n

comparing coefficients       (M1)

\n

hence  a = 6          A1

\n

 

\n

METHOD 3

\n

substitute  3 + i into  P ( z )        (M1)

\n

a ( 18 + 26 i ) 37 ( 8 + 6 i ) + 66 ( 3 + i ) 10 = 0        (M1)A1

\n

equating real or imaginary parts or dividing       M1

\n

18 a 296 + 198 10 = 0   or   26 a 222 + 66 = 0   or   10 66 ( 3 + i ) + 37 ( 8 + 6 i ) 18 + 26 i          A1

\n

hence  a = 6          A1

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.2.AHL.TZ0.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers" ] }, { "Question": "
\n

A Chocolate Shop advertises free gifts to customers that collect three vouchers. The vouchers are placed at random into 10% of all chocolate bars sold at this shop. Kati buys some of these bars and she opens them one at a time to see if they contain a voucher. Let \n\nP\n\n(\nX\n=\nn\n)\n be the probability that Kati obtains her third voucher on the \nn\n\nth\n\n bar opened.

\n

(It is assumed that the probability that a chocolate bar contains a voucher stays at 10% throughout the question.)

\n
\n

It is given that \n\nP\n\n(\nX\n=\nn\n)\n=\n\n\n\n\nn\n2\n\n\n+\na\nn\n+\nb\n\n\n2000\n\n\n×\n\n\n0.9\n\nn\n\n3\n\n\n\n for \nn\n\n3\n,\n\n \n\nn\n\n\nN\n\n.

\n
\n

Kati’s mother goes to the shop and buys \nx\n chocolate bars. She takes the bars home for Kati to open.

\n
\n

Show that P ( X = 3 ) = 0.001 and P ( X = 4 ) = 0.0027 .

\n
[3]
\n
a.
\n
\n

Find the values of the constants a and b .

\n
[5]
\n
b.
\n
\n

Deduce that P ( X = n ) P ( X = n 1 ) = 0.9 ( n 1 ) n 3 for n > 3 .

\n
[4]
\n
c.
\n
\n

(i)     Hence show that X has two modes m 1 and m 2 .

\n

(ii)     State the values of m 1 and m 2 .

\n
[5]
\n
d.
\n
\n

Determine the minimum value of x such that the probability Kati receives at least one free gift is greater than 0.5.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

P ( X = 3 ) = ( 0.1 ) 3    A1

\n

= 0.001    AG

\n

P ( X = 4 ) = P ( V V V ¯ V ) + P ( V V ¯ V V ) + P ( V ¯ V V V )    (M1)

\n

= 3 × ( 0.1 ) 3 × 0.9 (or equivalent)     A1

\n

= 0.0027    AG

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

attempting to form equations in a and b     M1

\n

9 + 3 a + b 2000 = 1 1000   ( 3 a + b = 7 )    A1

\n

16 + 4 a + b 2000 × 9 10 = 27 10 000   ( 4 a + b = 10 )    A1

\n

attempting to solve simultaneously     (M1)

\n

a = 3 ,   b = 2    A1

\n

METHOD 2

\n

P ( X = n ) = ( n 1 2 ) × 0.1 3 × 0.9 n 3    M1

\n

= ( n 1 ) ( n 2 ) 2000 × 0.9 n 3    (M1)A1

\n

= n 2 3 n + 2 2000 × 0.9 n 3    A1

\n

a = 3 , b = 2    A1

\n

 

\n

Note: Condone the absence of 0.9 n 3 in the determination of the values of a and b .

\n

 

\n

[5 marks]

\n
b.
\n
\n

METHOD 1

\n

EITHER

\n

P ( X = n ) = n 2 3 n + 2 2000 × 0.9 n 3    (M1)

\n

OR

\n

P ( X = n ) = ( n 1 2 ) × 0.1 3 × 0.9 n 3    (M1)

\n

THEN

\n

= ( n 1 ) ( n 2 ) 2000 × 0.9 n 3    A1

\n

P ( X = n 1 ) = ( n 2 ) ( n 3 ) 2000 × 0.9 n 4    A1

\n

P ( X = n ) P ( X = n 1 ) = ( n 1 ) ( n 2 ) ( n 2 ) ( n 3 ) × 0.9    A1

\n

= 0.9 ( n 1 ) n 3    AG

\n

METHOD 2

\n

P ( X = n ) P ( X = n 1 ) = n 2 3 n + 2 2000 × 0.9 n 3 ( n 1 ) 2 3 ( n 1 ) + 2 2000 × 0.9 n 4    (M1)

\n

= 0.9 ( n 2 3 n + 2 ) ( n 2 5 n + 6 )    A1A1

\n

 

\n

Note: Award A1 for a correct numerator and A1 for a correct denominator.

\n

 

\n

= 0.9 ( n 1 ) ( n 2 ) ( n 2 ) ( n 3 )    A1

\n

= 0.9 ( n 1 ) n 3    AG

\n

[4 marks]

\n
c.
\n
\n

(i)     attempting to solve 0.9 ( n 1 ) n 3 = 1 for n     M1

\n

n = 21    A1

\n

0.9 ( n 1 ) n 3 < 1 n > 21    R1

\n

0.9 ( n 1 ) n 3 > 1 n < 21    R1

\n

X has two modes     AG

\n

 

\n

Note: Award R1R1 for a clearly labelled graphical representation of the two inequalities (using P ( X = n ) P ( X = n 1 ) ).

\n

 

\n

(ii)     the modes are 20 and 21     A1

\n

[5 marks]

\n
d.
\n
\n

METHOD 1

\n

Y B ( x ,   0.1 )    (A1)

\n

attempting to solve P ( Y 3 ) > 0.5 (or equivalent eg  1 P ( Y 2 ) > 0.5 ) for x     (M1)

\n

 

\n

Note: Award (M1) for attempting to solve an equality (obtaining x = 26.4 ).

\n

 

\n

x = 27    A1

\n

METHOD 2

\n

n = 0 x P ( X = n ) > 0.5    (A1)

\n

attempting to solve for x     (M1)

\n

x = 27    A1

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "16N.2.AHL.TZ0.H_11", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Runners in an athletics club have season’s best times for the 100 m, which can be modelled by a normal distribution with mean 11.6 seconds and standard deviation 0.8 seconds. To qualify for a particular competition a runner must have a season’s best time of under 11 seconds. A runner from this club who has qualified for the competition is selected at random. Find the probability that he has a season’s best time of under 10.7 seconds.

\n
", "Markscheme": "
\n

T N ( 11.6 0.8 2 )

\n

P ( T < 10.7 | T < 11 )             (M1)

\n

= P ( T < 10.7 T < 11 ) P ( T < 11 )             (M1)

\n

= P ( T < 10.7 ) P ( T < 11 )             (M1)

\n

P ( T < 10.7 ) = 0.1302             (A1)

\n

P ( T < 11 ) = 0.2266             (A1)

\n

P ( T < 10.7 | T < 11 ) = 0.575             A1

\n

Note: Accept only 0.575.

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.2.AHL.TZ0.H_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Use the binomial theorem to expand cosθ+isinθ4. Give your answer in the form a+bi where a and b are expressed in terms of sinθ and cosθ.

\n
[3]
\n
a.
\n
\n

Use de Moivre’s theorem and the result from part (a) to show that cot4θ=cot4θ-6cot2θ+14cot3θ-4cotθ.

\n
[5]
\n
b.
\n
\n

Use the identity from part (b) to show that the quadratic equation x2-6x+1=0 has roots cot2π8 and cot23π8.

\n
[5]
\n
c.
\n
\n

Hence find the exact value of cot23π8.

\n
[4]
\n
d.
\n
\n

Deduce a quadratic equation with integer coefficients, having roots cosec2π8 and cosec23π8.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

uses the binomial theorem on cosθ+isinθ4       M1

\n

=C04cos4θ+C14cos3θisinθ+C24cos2θi2sin2θ+C34cosθi3sin3θ+C44i4sin4θ        A1

\n

=cos4θ-6cos2θsin2θ+sin4θ+i4cos3θsinθ-4cosθsin3θ        A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

(using de Moivre’s theorem with n=4 gives) cos4θ+isin4θ        (A1)

\n

equates both the real and imaginary parts of cos4θ+isin4θ and cos4θ-6cos2θsin2θ+sin4θ+i4cos3θsinθ-4cosθsin3θ       M1

\n

cos4θ=cos4θ-6cos2θsin2θ+sin4θ  and  sin4θ=4cos3θsinθ-4cosθsin3θ

\n

recognizes that cot4θ=cos4θsin4θ        (A1)

\n

substitutes for sin4θ and cos4θ into cos4θsin4θ       M1

\n

cot4θ=cos4θ-6cos2θsin2θ+sin4θ4cos3θsinθ-4cosθsin3θ

\n

divides the numerator and denominator by sin4θ to obtain

\n

cot4θ=cos4θ-6cos2θsin2θ+sin4θsin4θ4cos3θsinθ-4cosθsin3θsin4θ        A1

\n

cot4θ=cot4θ-6cot2θ+14cot3θ-4cotθ        AG

\n

 

\n

[5 marks]

\n
b.
\n
\n

setting cot4θ=0 and putting x=cot2θ in the numerator of cot4θ=cot4θ-6cot2θ+14cot3θ-4cotθ gives x2-6x+1=0        M1

\n

attempts to solve cot4θ=0 for θ        M1

\n

4θ=π2,3π2, 4θ=122n+1π,n=0,1,        (A1)

\n

θ=π8,3π8        A1

\n

 

\n

Note: Do not award the final A1 if solutions other than θ=π8,3π8 are listed.

\n

 

\n

finding the roots of cot4θ=0 θ=π8,3π8 corresponds to finding the roots of x2-6x+1=0 where x=cot2θ        R1

\n

so the equation x2-6x+1=0 as roots cot2π8 and cot23π8        AG

\n

 

\n

[5 marks]

\n
c.
\n
\n

attempts to solve x2-6x+1=0 for x        M1

\n

x=3±22        A1

\n

since cot2π8>cot23π8, cot23π8 has the smaller value of the two roots        R1

\n

 

\n

Note: Award R1 for an alternative convincing valid reason.

\n

 

\n

so cot23π8=3-22        A1

\n

 

\n

[4 marks]

\n
d.
\n
\n

let y=cosec2θ

\n

uses cot2θ=cosec2θ-1 where x=cot2θ        (M1)

\n

x2-6x+1=0y-12-6y-1+1=0        M1

\n

y2-8y+8=0        A1

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "EXN.1.AHL.TZ0.12", "topics": [ "topic-1-number-and-algebra", "topic-2-functions", "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer", "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers", "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots", "ahl-3-9-reciprocal-trig-ratios-and-their-pythagorean-identities-inverse-circular-functions" ] }, { "Question": "
\n

Eight boys and two girls sit on a bench. Determine the number of possible arrangements, given that

\n
\n

the girls do not sit together.

\n
[3]
\n
a.
\n
\n

the girls do not sit on either end.

\n
[2]
\n
b.
\n
\n

the girls do not sit on either end and do not sit together.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

METHOD 1

\n

10 ! 2 × 9 ! ( = 2903040 )             (A1)(A1)A1

\n

Note: Award A1 for  10 ! A1 for  2 × 9 ! A1 for final answer.

\n

 

\n

METHOD 2

\n

9 × 8 × 8 !             (A1)(A1)A1

\n

Note: Award A1 for 9 × 8 or equivalent, A1 for 8 ! and A1 for answer.

\n

 

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

8 × 7 × 8 ! ( = 2257920 )            (A1)A1

\n

Note: Award (A1) for 8 × 7 A1 for final answer.

\n

 

\n

METHOD 2

\n

10 ! 2 × 8 ! 2 × 2 × 7 × 8 !

\n

Note: Award A1 for 10 ! minus EITHER subtracted terms and A1 for final correct answer.

\n

 

\n

[2 marks]

\n
b.
\n
\n

METHOD 1

\n

8 × 7 × ( 8 ! 2 × 7 ! ) ( = 1693440 )           (A1)(A1)A1

\n

Note: Award (A1) for 8 × 7 , (A1) for  2 × 7 ! A1 for final answer.  ( 8 ! 2 × 7 ! ) can be replaced by  6 × 7 ! or 7 P 2 × 6 ! which may be awarded the second A1.

\n

 

\n

METHOD 2

\n

their answer to (a)  2 × 8 ! 2 × 2 × 7 × 8 !           (A1)(A1)A1

\n

Note: Award A1 for subtracting each of the terms and A1 for final answer.

\n

 

\n

METHOD 3

\n

their answer to (b)  2 × 7 × 8 !  or equivalent          (A1)A2

\n

Note: Award A1 for the subtraction and A2 for final answer.

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.2.AHL.TZ0.H_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

In Lucy’s music academy, eight students took their piano diploma examination and achieved scores out of 150. For her records, Lucy decided to record the average number of hours per week each student reported practising in the weeks prior to their examination. These results are summarized in the table below.

\n

\n
\n

Find Pearson’s product-moment correlation coefficient, r, for these data.

\n
[2]
\n
a.
\n
\n

The relationship between the variables can be modelled by the regression equation D=ah+b. Write down the value of a and the value of b.

\n
[1]
\n
b.
\n
\n

One of these eight students was disappointed with her result and wished she had practised more. Based on the given data, determine how her score could have been expected to alter had she practised an extra five hours per week.

\n
[2]
\n
c.
\n
\n

Lucy asserts that the number of hours a student practises has a direct effect on their final diploma result. Comment on the validity of Lucy’s assertion.

\n
[1]
\n
d.
\n
\n

Lucy suspected that each student had not been practising as much as they reported. In order to compensate for this, Lucy deducted a fixed number of hours per week from each of the students’ recorded hours.

\n

State how, if at all, the value of r would be affected.

\n
[1]
\n
e.
\n
", "Markscheme": "
\n

use of GDC to give                          (M1)

\n

r=0.883529

\n

r=0.884                         A1

\n


Note:
Award the (M1) for any correct value of r, a, b or r2=0.780624 seen in part (a) or part (b).

\n


[2 marks]

\n
a.
\n
\n

a=1.36609 , b=64.5171

\n

a=1.37 , b=64.5                       A1

\n



[1 mark]

\n
b.
\n
\n

attempt to find their difference                       (M1)

\n

5×1.36609  OR  1.36609h+5+64.5171-1.36609h+64.5171

\n

6.83045

\n

=6.83  6.85 from 1.37

\n

the student could have expected her score to increase by 7 marks.                       A1

\n


Note: Accept an increase of 6, 6.83 or 6.85.

\n


[2 marks]

\n
c.
\n
\n

Lucy is incorrect in suggesting there is a causal relationship.

\n

This might be true, but the data can only indicate a correlation.                     R1

\n


Note: Accept ‘Lucy is incorrect as correlation does not imply causation’ or equivalent.

\n


[1 mark]

\n
d.
\n
\n

no effect                 A1

\n


[1 mark]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21N.2.AHL.TZ0.1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A body moves in a straight line such that its velocity, \nv\n\n\nm\n\n\n\n\ns\n\n\n\n1\n\n\n\n, after \nt\n seconds is given by \nv\n=\n2\n\n\nsin\n\n\n(\n\n\nt\n\n10\n\n\n+\n\nπ\n5\n\n\n)\n\ncsc\n\n\n(\n\n\nt\n\n30\n\n\n+\n\nπ\n4\n\n\n)\n\n for \n0\n\nt\n\n60\n.

\n

The following diagram shows the graph of \nv\n against \nt\n. Point \n\nA\n\n is a local maximum and point \n\nB\n\n is a local minimum.

\n

\n
\n

The body first comes to rest at time \nt\n=\n\n\nt\n1\n\n\n. Find

\n
\n

Determine the coordinates of point A and the coordinates of point B .

\n
[4]
\n
a.i.
\n
\n

Hence, write down the maximum speed of the body.

\n
[1]
\n
a.ii.
\n
\n

the value of  t 1 .

\n
[2]
\n
b.i.
\n
\n

the distance travelled between  t = 0 and  t = t 1 .

\n
[2]
\n
b.ii.
\n
\n

the acceleration when t = t 1 .

\n
[2]
\n
b.iii.
\n
\n

Find the distance travelled in the first 30 seconds.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

A ( 7.47 2.28 )   and  B ( 43.4 , 2.45 )        A1A1A1A1

\n

[4 marks]

\n
a.i.
\n
\n

maximum speed is  2.45 ( m s 1 )        A1

\n

[1 mark]

\n
a.ii.
\n
\n

v = 0 t 1 = 25.1 ( s )       (M1)A1

\n

[2 marks]

\n
b.i.
\n
\n

0 t 1 v d t       (M1)

\n

= 41.0 ( m )        A1

\n

[2 marks]

\n
b.ii.
\n
\n

a = d v d t   at  t = t 1 = 25.1      (M1)

\n

a = 0.200 ( m s 2 )        A1

\n

Note: Accept  a = 0.2 .

\n

[2 marks]

\n
b.iii.
\n
\n

attempt to integrate between 0 and 30       (M1)

\n

Note: An unsupported answer of 38.6 can imply integrating from 0 to 30.

\n

 

\n

EITHER

\n

0 30 | v | d t        (A1)

\n

 

\n

OR

\n

41.0 t 1 30 v d t        (A1)

\n

 

\n

THEN

\n

= 43.3 ( m )        A1

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.2.AHL.TZ0.H_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

This question asks you to examine various polygons for which the numerical value of the area is the same as the numerical value of the perimeter. For example, a 3 by 6 rectangle has an area of 18 and a perimeter of 18.

\n

 

\n

For each polygon in this question, let the numerical value of its area be A and let the numerical value of its perimeter be P.

\n
\n

An n-sided regular polygon can be divided into n congruent isosceles triangles. Let x be the length of each of the two equal sides of one such isosceles triangle and let y be the length of the third side. The included angle between the two equal sides has magnitude 2πn.

\n

Part of such an n-sided regular polygon is shown in the following diagram.

\n

\n
\n

Consider a n-sided regular polygon such that A=P.

\n
\n

The Maclaurin series for tanx is x+x33+2x515+

\n
\n

Consider a right-angled triangle with side lengths a, b and a2+b2, where ab, such that A=P.

\n
\n

Find the side length, s, where s>0, of a square such that A=P.

\n
[3]
\n
a.
\n
\n

Write down, in terms of x and n, an expression for the area, AT, of one of these isosceles triangles.

\n
[1]
\n
b.
\n
\n

Show that y=2xsinπn.

\n
[2]
\n
c.
\n
\n

Use the results from parts (b) and (c) to show that A=P=4ntanπn.

\n
[7]
\n
d.
\n
\n

Use the Maclaurin series for tanx to find limn4ntanπn.

\n
[3]
\n
e.i.
\n
\n

Interpret your answer to part (e)(i) geometrically.

\n
[1]
\n
e.ii.
\n
\n

Show that a=8b-4+4.

\n
[7]
\n
f.
\n
\n

By using the result of part (f) or otherwise, determine the three side lengths of the only two right-angled triangles for which a, b, A, P.

\n
[3]
\n
g.i.
\n
\n

Determine the area and perimeter of these two right-angled triangles.

\n
[1]
\n
g.ii.
\n
", "Markscheme": "
\n

A=s2 and P=4s              (A1)

\n

A=Ps2=4s              (M1)

\n

ss-4=0

\n

s=4s>0        A1

\n

 

\n

Note: Award A1M1A0 if both s=4 and s=0 are stated as final answers.

\n

 

\n

[3 marks]

\n
a.
\n
\n

AT=12x2sin2πn        A1

\n

 

\n

Note: Award A1 for a correct alternative form expressed in terms of x and n only.

\n

          For example, using Pythagoras’ theorem, AT=xsinπnx2-x2sin2πn  or  AT=212xsinπnxcosπn  or  AT=x2sinπncosπn.

\n

 

\n

[1 mark]

\n
b.
\n
\n

METHOD 1

\n

uses sinθ=opphyp         (M1)

\n

y2x=sinπn        A1

\n

y=2xsinπn       AG

\n

 

\n

METHOD 2

\n

uses Pythagoras’ theorem y22+h2=x2  and  h=xcosπn         (M1)

\n

y22+xcosπn2=x2  y2=4x21-cos2πn

\n

=4x2sin2πn        A1

\n

y=2xsinπn       AG

\n

 

\n

METHOD 3

\n

uses the cosine rule         (M1)

\n

y2=2x2-2x2cos2πn =2x21-cos2πn

\n

=4x2sin2πn        A1

\n

y=2xsinπn       AG

\n

 

\n

METHOD 4

\n

uses the sine rule         (M1)

\n

ysin2πn=xsinπ2-πn

\n

ycosπn=2xsinπncosπn        A1

\n

y=2xsinπn       AG

\n

 

\n

[2 marks]

\n
c.
\n
\n

A=PnAT=ny         (M1)

\n

 

\n

Note: Award M1 for equating correct expressions for A and P.

\n

 

\n

12nx2sin2πn=2nxsinπn nx2sinπncosπn=2nxsinπn

\n

12x2sin2πn=2xsinπn x2sinπncosπn=2xsinπn        A1

\n

uses sin2πn=2sinπncosπn (seen anywhere in part (d) or in part (b))         (M1)

\n

x2sinπncosπn=2xsinπn

\n

attempts to either factorise or divide their expression         (M1)

\n

xsinπnxcosπn-2=0

\n

x=2cosπn, xsinπn0 (or equivalent)        A1

\n

 

\n

EITHER

\n

substitutes x=2cosπn (or equivalent) into P=ny         (M1)

\n

P=2n2cosπnsinπn        A1

\n


Note:
Other approaches are possible. For example, award A1 for P=2nxcosπntanπn and M1 for substituting x=2cosπn into P.

\n


OR

\n

substitutes x=2cosπn (or equivalent) into A=nAT          (M1)

\n

A=12n2cosπn2sin2πn

\n

A=12n2cosπn22sinπncosπn        A1

\n

 

\n

THEN

\n

A=P=4ntanπn       AG

\n

 

\n

[7 marks]

\n
d.
\n
\n

attempts to use the Maclaurin series for tanx with x=πn         (M1)

\n

tanπn=πn+πn33+2πn515+

\n

4ntanπn=4nπn+π33n3+2π515n5+ (or equivalent)        A1

\n

=4π+π33n2+2π515n4+

\n

limn4ntanπn=4π        A1

\n

 

\n

Note: Award a maximum of M1A1A0 if limn is not stated anywhere.

\n

 

\n

[3 marks]

\n
e.i.
\n
\n

(as n, P4π and A4π)

\n

the polygon becomes a circle of radius 2                   R1

\n

 

\n

Note: Award R1 for alternative responses such as:
the polygon becomes a circle of area 4π OR
the polygon becomes a circle of perimeter 4π OR
the polygon becomes a circle with A=P=4π.
Award R0 for polygon becomes a circle.

\n

 

\n

[1 mark]

\n
e.ii.
\n
\n

A=12ab and P=a+b+a2+b2                   (A1)(A1)

\n

equates their expressions for A and P                 M1

\n

A=Pa+b+a2+b2=12ab

\n

a2+b2=12ab-a+b                M1

\n

 

\n

Note: Award M1 for isolating a2+b2 or ±2a2+b2. This step may be seen later.

\n

 

\n

a2+b2=12ab-a+b2

\n

a2+b2=14a2b2-212aba+b+a+b2                M1

\n

=14a2b2-a2b-ab2+a2+2ab+b2

\n

 

\n

Note: Award M1 for attempting to expand their RHS of either a2+b2= or 4a2+b2=.

\n

 

\n

EITHER

\n

ab14ab-a-b+2=0  ab0               A1

\n

14ab-a-b+2=0

\n

ab-4a=4b-8

\n

 

\n

OR

\n

14a2b2-a2b-ab2+2ab=0

\n

a14b2-b+2b-b2=0  ab2-4b+8b-4b2=0               A1

\n

a=4b2-8bb2-4b

\n

 

\n

THEN

\n

a=4b-8b-4               A1

\n

a=4b-16+8b-4

\n

a=8b-4+4               AG

\n

 

\n

Note: Award a maximum of A1A1M1M1M0A0A0 for attempting to verify.
For example, verifying that A=P=16b-4+2b+4 gains 4 of the 7 marks.

\n

 

\n

[7 marks]

\n
f.
\n
\n

using an appropriate method          (M1)

\n

eg substituting values for b or using divisibility properties

\n

5,12,13 and 6,8,10             A1A1

\n

 

\n

Note: Award A1A0 for either one set of three correct side lengths or two sets of two correct side lengths.

\n

 

\n

[3 marks]

\n
g.i.
\n
\n

A=P=30  and  A=P=24            A1

\n

 

\n

Note: Do not award A1FT.

\n

 

\n

[1 mark]

\n
g.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.i.
\n
\n[N/A]\n
g.ii.
\n
", "question_id": "21M.3.AHL.TZ1.2", "topics": [ "topic-3-geometry-and-trigonometry", "topic-5-calculus" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area", "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Find the set of values of k that satisfy the inequality k 2 k 12 < 0 .

\n
[2]
\n
a.
\n
\n

The triangle ABC is shown in the following diagram. Given that cos B < 1 4 , find the range of possible values for AB.

\n

\"M17/5/MATHL/HP2/ENG/TZ2/04.b\"

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

k 2 k 12 < 0

\n

( k 4 ) ( k + 3 ) < 0      (M1)

\n

3 < k < 4      A1

\n

[2 marks]

\n
a.
\n
\n

cos B = 2 2 + c 2 4 2 4 c   ( or  16 = 2 2 + c 2 4 c cos B )      M1

\n

c 2 12 4 c < 1 4      A1

\n

c 2 c 12 < 0

\n

from result in (a)

\n

0 < AB < 4 or 3 < AB < 4      (A1)

\n

but AB must be at least 2

\n

2 < AB < 4      A1

\n

 

\n

Note:     Allow AB for either of the final two A marks.

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.AHL.TZ2.H_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A data set consisting of 16 test scores has mean 14.5 . One test score of 9 requires a second marking and is removed from the data set.

\n

Find the mean of the remaining 15 test scores.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

Σi=116xi16=14.5        (M1)

\n

 

\n

Note: Award M1 for use of x¯=Σi=1nxin.

\n

 

\n

Σi=116xi=232        (A1)

\n

new x¯=232-915        (A1)

\n

=14.9  =14.86¯,=22315        A1

\n

 

\n

Note: Do not accept 15.

\n

 

\n

[4 marks]

\n

 

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.2.SL.TZ0.1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

The following diagram shows a circle with centre O and radius 3.

\n

\n

Points A, P and B lie on the circumference of the circle.

\n

Chord AB has length L and AO^B=θ radians.

\n
\n

Show that arc APB has length 6π-3θ.

\n
[2]
\n
a.
\n
\n

Show that L=18-18cosθ.

\n
[2]
\n
b.
\n
\n

Arc APB is twice the length of chord AB.

\n

Find the value of θ.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

EITHER

\n

uses the arc length formula        (M1)

\n

arc length is 32π-θ        A1

\n

 

\n

OR

\n

length of arc AB is 3θ        A1

\n

the sum of the lengths of arc AB and arc APB is 6π        A1

\n

 

\n

THEN

\n

so arc APB has length 6π-3θ        AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

uses the cosine rule       (M1)

\n

L2=32+32-233cosθ        A1

\n

so L=18-18cosθ        AG

\n

 

\n

[2 marks]

\n
b.
\n
\n

6π-3θ=218-18cosθ        A1

\n

attempts to solve for θ       (M1)

\n

θ=2.49        A1

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXN.2.SL.TZ0.2", "topics": [ "topic-3-geometry-and-trigonometry", "topic-2-functions" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area", "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

Consider the following diagram.

\n

\n

The sides of the equilateral triangle ABC have lengths 1 m. The midpoint of [AB] is denoted by P. The circular arc AB has centre, M, the midpoint of [CP].

\n
\n

Find AM.

\n
[3]
\n
a.i.
\n
\n

Find \n\nA\n\n\n\nM\n\n\n\n\n\nP\n\n in radians.

\n
[2]
\n
a.ii.
\n
\n

Find the area of the shaded region.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

PC \n=\n\n\n\n3\n\n\n2\n\n or 0.8660       (M1)

\n

PM \n=\n\n1\n2\n\nPC \n=\n\n\n\n3\n\n\n4\n\n or 0.4330     (A1)

\n

AM \n=\n\n\n1\n4\n\n+\n\n3\n\n16\n\n\n\n

\n

\n=\n\n\n\n7\n\n\n4\n\n or 0.661 (m)     A1

\n

 

\n

METHOD 2

\n

using the cosine rule

\n

AM2 \n=\n\n\n1\n2\n\n\n+\n\n\n\n(\n\n\n\n\n3\n\n\n4\n\n\n)\n\n2\n\n\n\n2\n×\n\n\n\n3\n\n\n4\n\n×\n\ncos\n\n\n(\n\n\n30\n\n\n\n)\n\n      M1A1

\n

AM \n=\n\n\n\n7\n\n\n4\n\n or 0.661 (m)     A1

\n

[3 marks]

\n
a.i.
\n
\n

tan (\n\nA\n\n\n\nM\n\n\n\n\n\nP\n\n\n=\n\n2\n\n\n3\n\n\n\n or equivalent      (M1)

\n

= 0.857      A1

\n

[2 marks]

\n
a.ii.
\n
\n

EITHER

\n

\n\n1\n2\n\n\nA\n\n\n\n\nM\n\n2\n\n\n\n(\n\n2\n\n\nA\n\n\n\nM\n\n\n\n\n\nP\n\n\n\nsin\n\n\n(\n\n2\n\n\nA\n\n\n\nM\n\n\n\n\n\nP\n\n\n)\n\n\n)\n\n     (M1)A1

\n

OR

\n

\n\n1\n2\n\n\nA\n\n\n\n\nM\n\n2\n\n\n×\n2\n\n\nA\n\n\n\nM\n\n\n\n\n\nP\n\n\n=\n\n\n\n3\n\n\n8\n\n     (M1)A1

\n

= 0.158(m2)      A1

\n

Note: Award M1 for attempting to calculate area of a sector minus area of a triangle.

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.AHL.TZ2.H_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

Prove the identity p+q3-3pqp+qp3+q3.

\n
[2]
\n
a.
\n
\n

The equation 2x2-5x+1=0 has two real roots, α and β.

\n

Consider the equation x2+mx+n=0, where m, n and which has roots 1α3 and 1β3.
Without solving 2x2-5x+1=0, determine the values of m and n.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

p+q3-3pqp+qp3+q3

\n

attempts to expand p+q3                 M1

\n

p3+3p2q+3pq2+q3

\n

p+q3-3pqp+qp3+3p2q+3pq2+q3-3pqp+q

\n

p3+3p2q+3pq2+q3-3p2q-3pq2                 A1

\n

p3+q3                 AG

\n


Note: Condone the use of equals signs throughout.

\n

 

\n

METHOD 2

\n

p+q3-3pqp+qp3+q3

\n

attempts to factorise p+q3-3pqp+q                 M1

\n

p+qp+q2-3pq p+qp2-pq+q2

\n

p3-p2q+pq2+p2q-pq2+q3                 A1

\n

p3+q3                 AG

\n


Note: Condone the use of equals signs throughout.

\n

 

\n

METHOD 3

\n

p3+q3p+q3-3pqp+q

\n

attempts to factorise p3+q3                 M1

\n

p+qp2-pq+q2

\n

p+qp+q2-3pq                 A1

\n

p+q3-3pqp+q                 AG

\n


Note: 
Condone the use of equals signs throughout.

\n


[2 marks]

\n
a.
\n
\n

Note: Award a maximum of A1M0A0A1M0A0 for m=-95 and n=8 found by using α,β=5±174 α,β=0.219, 2.28.
Condone, as appropriate, solutions that state but clearly do not use the values of α and β.
Special case: Award a maximum of A1M1A0A1M0A0 for m=-95 and n=8 obtained by solving simultaneously for α and β from product of roots and sum of roots equations.

\n


product of roots of x2-52x+12=0

\n

αβ=12 (seen anywhere)                      A1

\n

considers 1α31β3 by stating 1αβ3=n                      M1

\n


Note: Award M1 for attempting to substitute their value of αβ into 1αβ3.

1αβ3=1123

\n

n=8                      A1

\n

sum of roots of x2-52x+12=0

\n

α+β=52 (seen anywhere)                A1

\n

considers 1α3 and 1β3 by stating α+β3-3αβα+βαβ3 α+βαβ3-3α+βαβ2=-m                      M1

\n


Note: Award M1 for attempting to substitute their values of α+b and αβ into their expression. Award M0 for use of α+β3-3αβα+β only.

\n


=523-325218 =125-30=95

\n

m=-95                A1

\n

x2-95x+8=0

\n


[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.2.AHL.TZ0.6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-6-simple-proof" ] }, { "Question": "
\n

In an arithmetic sequence, \n\n\nu\n2\n\n\n=\n5\n and \n\n\nu\n3\n\n\n=\n11\n.

\n
\n

Find the common difference.

\n
[2]
\n
a.
\n
\n

Find the first term.

\n
[2]
\n
b.
\n
\n

Find the sum of the first 20 terms.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

valid approach          (M1)

\n

eg    11 5 11 = 5 + d

\n

d = 6              A1  N2

\n

[2 marks]

\n
a.
\n
\n

valid approach          (M1)

\n

eg    u 2 d 5 6 u 1 + ( 3 1 ) ( 6 ) = 11

\n

u 1 = 1             A1  N2

\n

[2 marks]

\n
b.
\n
\n

correct substitution into sum formula

\n

eg    2022(1)+19(6) 20 2 ( 1 + 113 )         (A1)

\n

S 20 = 1120            A1  N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.1.SL.TZ0.S_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The following diagram shows a circle with centre O and radius r.

\n

\n

Points A and B lie on the circumference of the circle, and AO^B=1 radian.

\n

The perimeter of the shaded region is 12.

\n
\n

Find the value of r.

\n
[3]
\n
a.
\n
\n

Hence, find the exact area of the non-shaded region.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

minor arc AB has length r                  (A1)

\n

recognition that perimeter of shaded sector is 3r                     (A1)

\n

3r=12

\n

r=4               A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

EITHER
θ=2π-AO^B=2π-1             (M1)

\n

Area of non-shaded region =122π-142            (A1)

\n

 

\n

OR

\n

area of circle - area of shaded sector              (M1)

\n

16π-12×1×42              (A1)

\n

 

\n

THEN

\n

area =16π-8 =82π-1          A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.SL.TZ2.1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

A particle moves in a straight line such that its velocity, vms-1, at time t seconds is given by

\n

v=4t2-6t+9-2sin4t, 0t1.

\n

The particle’s acceleration is zero at t=T.

\n
\n

Find the value of T.

\n
[2]
\n
a.
\n
\n

Let s1 be the distance travelled by the particle from t=0 to t=T and let s2 be the distance travelled by the particle from t=T to t=1.

\n

Show that s2>s1.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

attempts either graphical or symbolic means to find the value of t when dvdt=0       (M1)

\n

T=0.465s        A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

attempts to find the value of either s1=00.46494vdt  or  s2=0.464941vdt       (M1)

\n

s1=3.02758 and s2=3.47892        A1A1

\n

 

\n

Note: Award as above for obtaining, for example, s2-s1=0.45133 or s2s1=1.14907

\n

Note: Award a maximum of M1A1A0FT for use of an incorrect value of T from part (a).

\n

 

\n

so s2>s1        AG

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "EXN.2.SL.TZ0.3", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

A continuous random variable X has a probability density function given by

\n

fx=arccosx 0x10otherwise

\n

The median of this distribution is m.

\n
\n

Determine the value of m.

\n
[2]
\n
a.
\n
\n

Given that PX-ma=0.3, determine the value of a.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

recognises that 0marccosxdx=0.5                     (M1)

\n

marccosm-1-m2-0-1=0.5

\n

m=0.360034

\n

m=0.360                     A1

\n


[2 marks]

\n
a.
\n
\n

METHOD 1

\n

attempts to find at least one endpoint (limit) both in terms of m (or their m) and a                     (M1)

\n

Pm-aXm+a=0.3                   

\n

0.360034-a0.360034+aarccosxdx=0.3                     (A1)

\n


Note: Award (A1) for m-am+aarccosxdx=0.3.

\n


xarccosx-1-x20.360034-a0.360034+a

\n

attempts to solve their equation for a                     (M1)

\n


Note:
The above (M1) is dependent on the first (M1).

\n


a=0.124861

\n

a=0.125                       A1

\n

 

\n

METHOD 2

\n

-aaarccos x-0.360034dx  =0.3                     (M1)(A1)

\n

 

\n

Note: Only award (M1) if at least one limit has been translated correctly.

\n

Note: Award (M1)(A1) for -aaarccos x-mdx  =0.3.

\n


attempts to solve their equation for a                     (M1)

\n

a=0.124861

\n

a=0.125                       A1

\n

 

\n

METHOD 3

\n

EITHER 

\n

-aaarccos x+0.360034dx  =0.3                     (M1)(A1)

\n

 

\n

Note: Only award (M1) if at least one limit has been translated correctly.

\n

Note: Award (M1)(A1) for -aaarccos x+mdx  =0.3.

\n


OR

\n

20.360034-a20.360034+aarccos x-0.360034dx  =0.3                     (M1)(A1)

\n


Note:
 Only award (M1) if at least one limit has been translated correctly.

\n

Note: Award (M1)(A1) for 2m-a2m+aarccos x-mdx  =0.3.

\n


THEN

\n

attempts to solve their equation for a                     (M1)

\n


Note:
 The above (M1) is dependent on the first (M1).

\n


a=0.124861

\n

a=0.125                       A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.2.AHL.TZ0.7", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

This diagram shows a metallic pendant made out of four equal sectors of a larger circle of radius \n\nOB\n\n=\n9\n\n cm\n\n and four equal sectors of a smaller circle of radius \n\nOA\n\n=\n3\n\n cm\n\n.
The angle \n\nBOC\n\n=\n 20°.

\n

\"N17/5/MATHL/HP2/ENG/TZ0/03\"

\n

Find the area of the pendant.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

area = (four sector areas radius 9) + (four sector areas radius 3)     (M1)

\n

\n=\n4\n\n(\n\n\n1\n2\n\n\n\n9\n2\n\n\n\nπ\n9\n\n\n)\n\n+\n4\n\n(\n\n\n1\n2\n\n\n\n3\n2\n\n\n\n\n7\nπ\n\n\n18\n\n\n\n)\n\n     (A1)(A1)

\n

\n=\n18\nπ\n+\n7\nπ\n

\n

\n=\n25\nπ\n\n \n\n(\n=\n78.5\n\n c\n\n\n\n\nm\n\n2\n\n\n)\n     A1

\n

METHOD 2

\n

area =

\n

(area of circle radius 3) + (four sector areas radius 9) – (four sector areas radius 3)     (M1)

\n

\nπ\n\n\n3\n2\n\n\n+\n4\n\n(\n\n\n1\n2\n\n\n\n9\n2\n\n\n\nπ\n9\n\n\n)\n\n\n4\n\n(\n\n\n1\n2\n\n\n\n3\n2\n\n\n\nπ\n9\n\n\n)\n\n     (A1)(A1)

\n

 

\n

Note:     Award A1 for the second term and A1 for the third term.

\n

 

\n

\n=\n9\nπ\n+\n18\nπ\n\n2\nπ\n

\n

\n=\n25\nπ\n\n \n\n(\n=\n\n \n\n78.5\n\n c\n\n\n\n\nm\n\n2\n\n\n)\n     A1

\n

 

\n

Note:     Accept working in degrees.

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.2.AHL.TZ0.H_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

Consider two consecutive positive integers, n and n+1.

\n

Show that the difference of their squares is equal to the sum of the two integers.

\n
", "Markscheme": "
\n

attempt to subtract squares of integers            (M1)

\n

n+12-n2

\n

 

\n

EITHER

\n

correct order of subtraction and correct expansion of n+12, seen anywhere            A1A1

\n

=n2+2n+1n2 (=2n+1)

\n

 

\n

OR

\n

correct order of subtraction and correct factorization of difference of squares          A1A1

\n

=(n+1n)(n+1+n)(=2n+1)

\n

 

\n

THEN

\n

=n+n+1=RHS             A1

\n

 

\n

Note: Do not award final A1 unless all previous working is correct.

\n

 

\n

which is the sum of n and n+1            AG

\n

 

\n

Note: If expansion and order of subtraction are correct, award full marks for candidates who find the sum of the integers as 2n+1 and then show that the difference of the squares (subtracted in the correct order) is 2n+1.

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.SL.TZ2.2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-6-simple-proof" ] }, { "Question": "
\n

Consider the curve C given by y=x-xyln(xy) where x>0, y>0.

\n
\n

Show that dydx+xdydx+y1+lnxy=1.

\n
[3]
\n
a.
\n
\n

Hence find the equation of the tangent to C at the point where x=1.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

attempts to differentiate implicitly including at least one application of the product rule                   (M1)

\n

u=xy, v=lnxy, dudx=xdydx+y, dvdx=xdydx+y1xy

\n

dydx=1-xyxyxdydx+y+xdydx+ylnxy                       A1

\n


Note: Award (M1)A1 for implicitly differentiating y=x1-ylnxy and obtaining dydx=1-xyxyxdydx+y+xdydxlnxy+ylnxy.

\n

 

\n

dydx=1-xdydx+y+xdydx+ylnxy

\n

dydx=1-xdydx+y1+lnxy                      A1

\n

dydx+xdydx+y1+lnxy=1                      AG

\n

 

\n

METHOD 2

\n

y=x-xylnx-xylny

\n

attempts to differentiate implicitly including at least one application of the product rule                   (M1)

\n

dydx=1-xyx+xdydx+ylnx-xyydydx+xdydx+ylny                      A1

\n

or equivalent to the above, for example

\n

dydx=1-xlnxdydx+1+lnxy-ylny+xlnydydx+dydx

\n

dydx=1-xdydxlnx+lny+1-ylnx+lny+1                      A1

\n

or equivalent to the above, for example

\n

dydx=1-xdydxlnxy+1-ylnxy+1

\n

dydx+xdydx+y1+lnxy=1                      AG

\n

 

\n

METHOD 3

\n

attempt to differentiate implicitly including at least one application of the product rule             M1

\n

u=xlnxy, v=y, dudx=lnxy+xdydx+yxxy, dvdx=dydx

\n

dydx=1-xdydxlnxy+ylnxy+xyxyxdydx+y                      A1

\n

dydx=1-xdydxlnxy+1-ylnxy+1                      A1

\n

dydx+xdydx+y1+lnxy=1                      AG

\n

 

\n

METHOD 4

\n

lets w=xy and attempts to find dydx where y=x-wlnw             M1

\n

dydx=1-dwdx+dwdxlnw =1-dwdx1+lnw                      A1

\n

dwdx=xdydx+y                      A1

\n

dydx=1-xdydx+y+xdydx+ylnxy  =1-xdydx+y1+lnxy

\n

dydx+xdydx+y1+lnxy=1                      AG

\n

 

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

substitutes x=1 into y=x-xylnxy                  (M1)

\n

y=1-ylnyy=1                       A1

\n

substitutes x=1 and their non-zero value of y into dydx+xdydx+y1+lnxy=1                  (M1)

\n

2dydx=0  dydx=0                       A1

\n

equation of the tangent is y=1                       A1

\n

 

\n

METHOD 2

\n

substitutes x=1 into dydx+xdydx+y1+lnxy=1                 (M1)

\n

dydx+dydx+y1+lny=1

\n


EITHER

\n

correctly substitutes lny=1-yy into dydx+dydx+y1+lnxy=1                       A1

\n

dydx1+1y=0dydx=0 y=1                       A1

\n


OR

\n

correctly substitutes y+ylny=1 into dydx+dydx+y1+lnxy=1                       A1

\n

dydx2+lny=0dydx=0 y=1                       A1

\n


THEN

\n

substitutes x=1 into y=x-xylnxy                 (M1)

\n

y=1-ylnyy=1

\n

equation of the tangent is y=1                       A1

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.2.AHL.TZ0.8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

The following table shows the systolic blood pressures, p mmHg, and the ages, t years, of 6 male patients at a medical clinic.

\n

\n
\n

The relationship between t and p can be modelled by the regression line of p on t with equation p=at+b .

\n
\n

A 50‐year‐old male patient enters the medical clinic for his appointment.

\n
\n

Determine the value of Pearson’s product‐moment correlation coefficient, r, for these data.

\n
[2]
\n
a.i.
\n
\n

Interpret, in context, the value of r found in part (a) (i).

\n
[1]
\n
a.ii.
\n
\n

Find the equation of the regression line of p on t.

\n
[2]
\n
b.
\n
\n

Use the regression equation from part (b) to predict this patient’s systolic blood pressure.

\n
[2]
\n
c.
\n
\n

A 16‐year‐old male patient enters the medical clinic for his appointment.

\n

Explain why the regression equation from part (b) should not be used to predict this patient’s systolic blood pressure.

\n
[1]
\n
d.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

r=0.946      A2

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

the value of r shows a (very) strong positive correlation between age and (systolic) blood pressure     A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

p=1.05t+69.3     A1A1

\n

 

\n

Note: Only award marks for an equation. Award A1 for a=1.05 and A1 for b=69.3. Award A1A0 for y=1.05x+69.3.

\n

 

\n

[2 marks]

\n
b.
\n
\n

122 (mmHg)     (M1)A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

the regression equation should not be used because it involves extrapolation    A1

\n

 

\n

[1 mark]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "EXN.2.SL.TZ0.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Let \ng\n\n(\nx\n)\n\n=\n\n\np\nx\n\n\n+\nq\n, for \nx\n\n\n\np\n\n\n\nq\n\n\nR\n\n\n\n\np\n>\n1\n. The point \n\nA\n\n\n(\n\n0\n\n\n\na\n\n)\n\n lies on the graph of \ng\n.

\n

Let \nf\n\n(\nx\n)\n\n=\n\n\ng\n\n\n1\n\n\n\n\n(\nx\n)\n\n. The point \n\nB\n\n lies on the graph of \nf\n and is the reflection of point \n\nA\n\n in the line \ny\n=\nx\n.

\n
\n

The line \n\n\nL\n1\n\n\n is tangent to the graph of \nf\n at \n\nB\n\n.

\n
\n

Write down the coordinates of B .

\n
[2]
\n
a.
\n
\n

Given that  f ( a ) = 1 ln p , find the equation of L 1 in terms of x , p and q .

\n
[5]
\n
b.
\n
\n

The line L 2 is tangent to the graph of g at A and has equation  y = ( ln p ) x + q + 1 .

\n

The line L 2 passes through the point  ( 2 2 ) .

\n

The gradient of the normal to g at A is  1 ln ( 1 3 ) .

\n

 

\n

Find the equation of L 1 in terms of x .

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

B ( a 0 )   (accept   B ( q + 1 0 ) )           A2   N2

\n

[2 marks]

\n
a.
\n
\n

Note: There are many approaches to this part, and the steps may be done in any order. Please check working and award marks in line with the markscheme, noting that candidates may work with the equation of the line before finding a .

\n

 

\n

FINDING a

\n

valid attempt to find an expression for a in terms of q        (M1)

\n

g ( 0 ) = a p 0 + q = a

\n

a = q + 1        (A1)

\n

 

\n

FINDING THE EQUATION OF  L 1

\n

EITHER

\n

attempt to substitute tangent gradient and coordinates into equation of straight line        (M1)

\n

eg        y 0 = f ( a ) ( x a ) y = f ( a ) ( x ( q + 1 ) )

\n

correct equation in terms of a and p        (A1)

\n

eg        y 0 = 1 ln ( p ) ( x a )

\n

OR

\n

attempt to substitute tangent gradient and coordinates to find b

\n

eg        0 = 1 ln ( p ) ( a ) + b

\n

b = a ln ( p )        (A1)

\n

THEN (must be in terms of both p and q )

\n

y = 1 ln p ( x q 1 ) y = 1 ln p x q + 1 ln p            A1   N3

\n

Note: Award A0 for final answers in the form  L 1 = 1 ln p ( x q 1 )

\n

 

\n

[5 marks]

\n
b.
\n
\n

Note: There are many approaches to this part, and the steps may be done in any order. Please check working and award marks in line with the markscheme, noting that candidates may find q in terms of p before finding a value for p .

\n

 

\n

FINDING p

\n

valid approach to find the gradient of the tangent      (M1)

\n

eg      m1m2=111ln(13)ln(13)1lnp=1ln(13)

\n

correct application of log rule (seen anywhere)       (A1)

\n

eg        ln ( 1 3 ) 1 ( ln ( 1 ) ln ( 3 ) )

\n

correct equation (seen anywhere)           A1

\n

eg        ln p = ln 3 p = 3

\n

 

\n

FINDING q

\n

correct substitution of  ( 2 2 ) into  L 2 equation        (A1)

\n

eg        2 = ( ln p ) ( 2 ) + q + 1

\n

q = 2 ln p 3 q = 2 ln 3 3   (seen anywhere)           A1

\n

 

\n

FINDING L 1

\n

correct substitution of their p and q into their L 1         (A1)

\n

eg        y = 1 ln 3 ( x ( 2 ln 3 3 ) 1 )

\n

y = 1 ln 3 ( x 2 ln 3 + 2 ) y = 1 ln 3 x 2 ln 3 2 ln 3            A1   N2

\n

 

\n

Note: Award A0 for final answers in the form L 1 = 1 ln 3 ( x 2 ln 3 + 2 ) .

\n

 

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.1.SL.TZ0.S_10", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

The diagram shows two circles with centres at the points A and B and radii \n2\nr\n and \nr\n, respectively. The point B lies on the circle with centre A. The circles intersect at the points C and D.

\n

\"N16/5/MATHL/HP2/ENG/TZ0/09\"

\n

Let \nα\n be the measure of the angle CAD and \nθ\n be the measure of the angle CBD in radians.

\n
\n

Find an expression for the shaded area in terms of \nα\n, \nθ\n and \nr\n.

\n
[3]
\n
a.
\n
\n

Show that \nα\n=\n4\narcsin\n\n\n1\n4\n\n.

\n
[2]
\n
b.
\n
\n

Hence find the value of \nr\n given that the shaded area is equal to 4.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nA\n=\n2\n(\nα\n\nsin\n\nα\n)\n\n\nr\n2\n\n\n+\n\n1\n2\n\n(\nθ\n\nsin\n\nθ\n)\n\n\nr\n2\n\n\n    M1A1A1

\n

 

\n

Note: Award M1A1A1 for alternative correct expressions eg. \nA\n=\n4\n\n(\n\n\nα\n2\n\n\nsin\n\n\nα\n2\n\n\n)\n\n\n\nr\n2\n\n\n+\n\n1\n2\n\nθ\n\n\nr\n2\n\n\n.

\n

 

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

consider for example triangle ADM where M is the midpoint of BD     M1

\n

\nsin\n\n\nα\n4\n\n=\n\n1\n4\n\n    A1

\n

\n\nα\n4\n\n=\narcsin\n\n\n1\n4\n\n

\n

\nα\n=\n4\narcsin\n\n\n1\n4\n\n    AG

\n

METHOD 2

\n

attempting to use the cosine rule (to obtain \n1\n\ncos\n\n\nα\n2\n\n=\n\n1\n8\n\n)     M1

\n

\nsin\n\n\nα\n4\n\n=\n\n1\n4\n\n (obtained from \nsin\n\n\nα\n4\n\n=\n\n\n\n1\n\ncos\n\n\nα\n2\n\n\n2\n\n\n)     A1

\n

\n\nα\n4\n\n=\narcsin\n\n\n1\n4\n\n

\n

\nα\n=\n4\narcsin\n\n\n1\n4\n\n    AG

\n

METHOD 3

\n

\nsin\n\n\n(\n\n\nπ\n2\n\n\n\nα\n4\n\n\n)\n\n=\n2\nsin\n\n\nα\n2\n\n where \n\nθ\n2\n\n=\n\nπ\n2\n\n\n\nα\n4\n\n

\n

\ncos\n\n\nα\n4\n\n=\n4\nsin\n\n\nα\n4\n\ncos\n\n\nα\n4\n\n    M1

\n

 

\n

Note: Award M1 either for use of the double angle formula or the conversion from sine to cosine.

\n

 

\n

\n\n1\n4\n\n=\nsin\n\n\nα\n4\n\n    A1

\n

\n\nα\n4\n\n=\narcsin\n\n\n1\n4\n\n

\n

\nα\n=\n4\narcsin\n\n\n1\n4\n\n    AG

\n

[2 marks]

\n
b.
\n
\n

(from triangle ADM), \nθ\n=\nπ\n\n\nα\n2\n\n\n \n\n\n(\n\n=\nπ\n\n2\narcsin\n\n\n1\n4\n\n=\n2\narcsin\n\n\n1\n4\n\n=\n2.6362\n\n\n)\n\n     A1

\n

attempting to solve \n2\n(\nα\n\nsin\n\nα\n)\n\n\nr\n2\n\n\n+\n\n1\n2\n\n(\nθ\n\nsin\n\nθ\n)\n\n\nr\n2\n\n\n=\n4\n

\n

with \nα\n=\n4\narcsin\n\n\n1\n4\n\n and \nθ\n=\nπ\n\n\nα\n2\n\n\n \n\n\n(\n\n=\n2\narccos\n\n\n1\n4\n\n\n)\n\n for \nr\n     (M1)

\n

\nr\n=\n1.69\n    A1

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.2.AHL.TZ0.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

In a class of \n30\n students, \n18\n are fluent in Spanish, \n10\n are fluent in French, and \n5\n are not fluent in either of these languages. The following Venn diagram shows the events “fluent in Spanish” and “fluent in French”.

\n

The values \nm\n, \nn\n, \np\n and \nq\n represent numbers of students.

\n

\n
\n

Write down the value of q .

\n
[1]
\n
a.
\n
\n

Find the value of n .

\n
[2]
\n
b.
\n
\n

Write down the value of m and of p .

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

q = 5            A1  N1

\n

[1 mark]

\n
a.
\n
\n

valid approach       (M1)

\n

eg    ( 18 + 10 + 5 ) 30 ,   28 25 ,   18 + 10 n = 25

\n

n = 3           A1  N2

\n

[2 marks]

\n
b.
\n
\n

valid approach for finding m or p (may be seen in part (b))      (M1)

\n

eg    18 3 3 + p = 10

\n

m = 15 p = 7          A1A1  N3

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.1.SL.TZ0.S_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Show that the equation 2cos2x+5sinx=4 may be written in the form 2sin2x-5sinx+2=0.

\n
[1]
\n
a.
\n
\n

Hence, solve the equation 2cos2x+5sinx=4, 0x2π.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

correct substitution of cos2x=1-sin2x            A1

\n

21-sin2x+5sinx=4

\n

2sin2x-5sinx+2=0          AG

\n

 

\n

METHOD 2

\n

correct substitution using double-angle identities             A1

\n

2cos2x-1+5sinx=3

\n

1-2sin2x-5sinx=3

\n

2sin2x-5sinx+2=0           AG

\n

 

\n

[1 mark]

\n
a.
\n
\n

EITHER

\n

attempting to factorise              M1

\n

(2sinx1)(sinx2)                   A1

\n

 

\n

OR

\n

attempting to use the quadratic formula            M1

\n

sinx=5±52-4×2×24=5±34         A1

\n

 

\n

THEN

\n

sinx=12           (A1)

\n

x=π6,5π6                  A1A1

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.SL.TZ2.3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-6-pythagorean-identity-double-angles" ] }, { "Question": "
\n

In the expansion of (x+k)7, where k, the coefficient of the term in x5 is 63.

\n

Find the possible values of k.

\n
", "Markscheme": "
\n

EITHER

\n

attempt to use the binomial expansion of x+k7          (M1)

\n

C07x7k0+C17x6k1+C27x5k2+  (or C07k7x0+C17k5x1+C27k5x2+)

\n

identifying the correct term C27x5k2  (or C57k2x5)             (A1)

\n

 

\n

OR

\n

attempt to use the general term Cr7xrk7-r  (or Cr7krx7-r)           (M1)

\n

r=2 (or r=5)            (A1)

\n

 

\n

THEN

\n

C27=21  (or C57=21 (seen anywhere)            (A1)

\n

21x5k2=63x5  21k2=63 , k2=3          A1

\n

k=±3             A1

\n

 

\n

Note: If working shown, award M1A1A1A1A0 for k=3.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.SL.TZ2.4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Let \ng\n\n(\nx\n)\n\n=\n\n\nx\n2\n\n\n+\nb\nx\n+\n11\n. The point \n\n(\n\n\n1\n\n\n\n8\n\n)\n\n lies on the graph of \ng\n.

\n
\n

Find the value of b .

\n
[3]
\n
a.
\n
\n

The graph of  f ( x ) = x 2  is transformed to obtain the graph of g .

\n

Describe this transformation.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

valid attempt to substitute coordinates      (M1)

\n

eg     g ( 1 ) = 8

\n

correct substitution      (A1)

\n

eg     ( 1 ) 2 + b ( 1 ) + 11 = 8 ,   1 b + 11 = 8

\n

b = 4         A1  N2

\n

[3 marks]

\n
a.
\n
\n

valid attempt to solve     (M1)

\n

eg    ( x 2 + 4 x + 4 ) + 7 ,   h = 4 2 ,   k = g ( 2 )

\n

correct working        A1

\n

eg     ( x + 2 ) 2 + 7 ,   h = 2 ,   k = 7

\n

translation or shift (do not accept move) of vector  ( 2 7 )  (accept left by 2 and up by 7 )        A1A1  N2

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.1.SL.TZ0.S_3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing" ] }, { "Question": "
\n

Consider the function f defined by f(x)=ln(x2-16) for x>4.

\n

The following diagram shows part of the graph of f which crosses the x-axis at point A, with coordinates (a, 0). The line L is the tangent to the graph of f at the point B.

\n

\n
\n

Find the exact value of a.

\n
[3]
\n
a.
\n
\n

Given that the gradient of L is 13, find the x-coordinate of B.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

lnx2-16=0             (M1)

\n

e0=x2-16=1

\n

x2=17  OR  x=±17                (A1)

\n

a=17           A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to differentiate (must include 2x and/or 1x2-16)             (M1)

\n

f'x=2xx2-16           A1

\n

setting their derivative =13           M1

\n

2xx2-16=13

\n

x2-16=6x  OR  x2-6x-16=0 (or equivalent)           A1

\n

valid attempt to solve their quadratic             (M1)

\n

x=8           A1

\n

 

\n

Note: Award A0 if the candidate’s final answer includes additional solutions (such as x=2, 8).

\n

 

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.SL.TZ2.5", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-9-exponential-and-logarithmic-functions", "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

The following diagram shows triangle ABC, with AB=10, BC=x and AC=2x.

\n

\n

Given that cosC^=34, find the area of the triangle.

\n

Give your answer in the form pq2 where p, q+.

\n
", "Markscheme": "
\n

METHOD 1

\n

attempt to use the cosine rule to find the value of x             (M1)

\n

100=x2+4x2-2x2x34           A1

\n

2x2=100

\n

x2=50  OR  x=50  =52           A1

\n

attempt to find sinC^  (seen anywhere)             (M1)

\n

sin2C^+342=1  OR  x2+32=42 or right triangle with side 3 and hypotenuse 4

\n

sinC^=74             (A1)

\n


Note:
The marks for finding sinC^ may be awarded independently of the first three marks for finding x.

\n


correct substitution into the area formula using their value of x (or x2) and their value of sinC^            (M1)

\n

A=12×52×102×74  or  A=12×50×250×74

\n

A=2572           A1

\n

 

\n

METHOD 2

\n

attempt to find the height, h, of the triangle in terms of x           (M1)

\n

h2+34x2=x2  OR  h2+54x2=102  OR  h=74x           A1

\n

equating their expressions for either h2 or h           (M1)

\n

x2-34x2=102-54x2  OR  100-2516x2=74x (or equivalent)           A1

\n

x2=50  OR  x=50  =52           A1

\n

correct substitution into the area formula using their value of x (or x2)           (M1)

\n

A=12×250×7450  OR  A=122×527452

\n

A=2572           A1

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.SL.TZ2.6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The quadratic equation k-1x2+2x+2k-3=0, where k, has real distinct roots.

\n

Find the range of possible values for k.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

 

\n

attempts to find an expression for the discriminant, Δ, in terms of k       (M1)

\n

Δ=4-4k-12k-3  =-8k2+20k-8       (A1)

\n

 

\n

Note: Award M1A1 for finding x=-2±4-4k-12k-32k-1.

\n

 

\n

attempts to solve Δ>0 for k       (M1)

\n

 

\n

Note: Award M1 for attempting to solve Δ=0 for k.

\n

 

\n

12<k<2        A1A1

\n

 

\n

Note: Award A1 for obtaining critical values k=12,2 and A1 for correct inequality signs.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.2.SL.TZ0.5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

The height of water, in metres, in Dungeness harbour is modelled by the function H(t)=asin(b(t-c))+d, where t is the number of hours after midnight, and a, b, c and d are constants, where a>0, b>0 and c>0.

\n

The following graph shows the height of the water for 13 hours, starting at midnight.

\n

\n

The first high tide occurs at 04:30 and the next high tide occurs 12 hours later. Throughout the day, the height of the water fluctuates between 2.2m and 6.8m.

\n

All heights are given correct to one decimal place.

\n
\n

Show that b=π6.

\n
[1]
\n
a.
\n
\n

Find the value of a.

\n
[2]
\n
b.
\n
\n

Find the value of d.

\n
[2]
\n
c.
\n
\n

Find the smallest possible value of c.

\n
[3]
\n
d.
\n
\n

Find the height of the water at 12:00.

\n
[2]
\n
e.
\n
\n

Determine the number of hours, over a 24-hour period, for which the tide is higher than 5 metres.

\n
[3]
\n
f.
\n
\n

A fisherman notes that the water height at nearby Folkestone harbour follows the same sinusoidal pattern as that of Dungeness harbour, with the exception that high tides (and low tides) occur 50 minutes earlier than at Dungeness.

\n

Find a suitable equation that may be used to model the tidal height of water at Folkestone harbour.

\n
[2]
\n
g.
\n
", "Markscheme": "
\n

12=2πb  OR  b=2π12                A1

\n

b=π6                AG

\n

 

\n

[1 mark]

\n
a.
\n
\n

a=6.8-2.22  OR  a=max-min2                (M1)

\n

=2.3m                A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

d=6.8+2.22  OR  d=max+min2                (M1)

\n

=4.5m                A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

METHOD 1

\n

substituting t=4.5 and H=6.8 for example into their equation for H                (A1)

\n

6.8=2.3sinπ64.5-c+4.5

\n

attempt to solve their equation                (M1)

\n

c=1.5                A1

\n

 

\n

METHOD 2

\n

using horizontal translation of 124                (M1)

\n

4.5-c=3                (A1)

\n

c=1.5                A1

\n

 

\n

METHOD 3

\n

H't=2.3π6cosπ6t-c                (A1)

\n

attempts to solve their H'4.5=0 for c                (M1)

\n

2.3π6cosπ64.5-c=0

\n

c=1.5                A1

\n

 

\n

[3 marks]

\n
d.
\n
\n

attempt to find H when t=12 or t=0, graphically or algebraically                (M1)

\n

H=2.87365

\n

H=2.87m                A1

\n

 

\n

[2 marks]

\n
e.
\n
\n

attempt to solve 5=2.3sinπ6t-1.5+4.5                (M1)

\n

times are t=1.91852 and t=7.08147 , t=13.9185, t=19.0814                (A1)

\n

total time is 2×7.081-1.919

\n

10.3258

\n

=10.3 (hours)                A1

\n


Note: Accept 10.

\n

 

\n

[3 marks]

\n
f.
\n
\n

METHOD 1

\n

substitutes t=113 and H=6.8 into their equation for H and attempts to solve for c                (M1)

\n

6.8=2.3sinπ6113-c+4.5c=23

\n

Ht=2.3sinπ6t-23+4.5                A1

\n

 

\n

METHOD 2
uses their horizontal translation 124=3                (M1)

\n

113-c=3c=23

\n

Ht=2.3sinπ6t-23+4.5                A1

\n

 

\n

[2 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "21N.2.AHL.TZ0.9", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

Consider the curves y=x2sinx and y=-1-1+4x+22 for -πx0.

\n
\n

Find the x-coordinates of the points of intersection of the two curves.

\n
[3]
\n
a.
\n
\n

Find the area, A, of the region enclosed by the two curves.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

attempts to solve x2sinx=-1-1+4x+22       (M1)

\n

x=-2.76,-1.54        A1A1

\n

 

\n

Note: Award A1A0 if additional solutions outside the domain are given.

\n

 

\n

[3 marks]

\n
a.
\n
\n

A=-2.762-1.537-1-1+4x+22-x2sinxdx (or equivalent)       (M1)(A1)

\n

 

\n

Note: Award M1 for attempting to form an integrand involving “top curve” − “bottom curve”.

\n

 

\n

so A=1.47          A2

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "EXN.2.SL.TZ0.6", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-11-definite-integrals-areas-under-curve-onto-x-axis-and-areas-between-curves" ] }, { "Question": "
\n

A large school has students from Year 6 to Year 12.

\n

A group of 80 students in Year 12 were randomly selected and surveyed to find out how many hours per week they each spend doing homework. Their results are represented by the following cumulative frequency graph.

\n

\n
\n

This same information is represented by the following table.

\n

\n
\n

There are 320 students in Year 12 at this school.

\n
\n

Find the median number of hours per week these Year 12 students spend doing homework.

\n
[2]
\n
a.
\n
\n

Given that 10% of these Year 12 students spend more than k hours per week doing homework, find the value of k.

\n
[3]
\n
b.
\n
\n

Find the value of p and the value of q.

\n
[4]
\n
c.
\n
\n

Estimate the number of Year 12 students that spend more than 15 hours each week doing homework.

\n
[3]
\n
d.
\n
\n

Explain why this sampling method might not provide an accurate representation of the amount of time all of the students in the school spend doing homework.

\n
[1]
\n
e.i.
\n
\n

Suggest a more appropriate sampling method.

\n
[1]
\n
e.ii.
\n
", "Markscheme": "
\n

evidence of median position             (M1)

\n

40 students

\n

median =14 (hours)           A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

recognizing there are 8 students in the top 10%             (M1)

\n

72 students spent less than k hours             (A1)

\n

k=18 (hours)           A1

\n

 

\n

[3 marks]

\n
b.
\n
\n

15 hours is 60 students  OR  p=60-4             (M1)

\n

p=56           A1

\n

21 hours is 76 students  OR  q=8076  OR  q=8045616             (A1)

\n

q=4           A1

\n

 

\n

[4 marks]

\n
c.
\n
\n

20 of the 80 students OR 14 spend more than 15 hours doing homework             (A1)

\n

2080=x320  OR  14×320  OR  4×20             (A1)

\n

80 (students)           A1

\n

 

\n

[3 marks]

\n
d.
\n
\n

only year 12 students surveyed OR amount of homework might be different for different year levels        R1

\n

 

\n

[1 mark]

\n
e.i.
\n
\n

stratified sampling OR survey students in all years     R1

\n

 

\n

[1 mark]

\n
e.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
", "question_id": "21M.1.SL.TZ2.7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots", "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

Consider \n\n(\n\n\n\n\n\n11\n\n\n\n\n\na\n\n\n\n\n)\n\n=\n\n\n11\n\n!\n\n\n\na\n\n!\n\n\n9\n\n!\n\n\n\n.

\n
\n

Find the value of a .

\n
[2]
\n
a.
\n
\n

Hence or otherwise find the coefficient of the term in  x 9 in the expansion of ( x + 3 ) 11 .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

valid approach    (M1)

\n

eg    11 a = 9 11 ! 9 ! ( 11 9 ) !

\n

a = 2         A1  N2

\n

[2 marks]

\n
a.
\n
\n

valid approach for expansion using n = 11     (M1)

\n

eg    ( 11 r ) x 11 r 3 r a 11 b 0 + ( 11 1 ) a 10 b 1 + ( 11 2 ) a 9 b 2 +

\n

evidence of choosing correct term         A1

\n

eg     ( 11 2 ) 3 2 ,   ( 11 2 ) x 9 3 2 ,   ( 11 9 ) 3 2

\n

correct working for binomial coefficient (seen anywhere, do not accept factorials)         A1

\n

eg     55 ,   ( 11 2 ) = 55 ,   55 × 3 2 ,   ( 55 × 9 ) x 9 ,   11 × 10 2 × 9

\n

495         A1  N2

\n

Note: If there is clear evidence of adding instead of multiplying, award A1 for the correct working for binomial coefficient, but no other marks. For example,  55 x 9 × 3 2  would earn M0A0A1A0.

\n

Do not award final A1 for a final answer of  495 x 9 , even if  495  is seen previously. If no working shown, award N1 for  495 x 9 .

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.1.SL.TZ0.S_4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Helen and Jane both commence new jobs each starting on an annual salary of $70,000. At the start of each new year, Helen receives an annual salary increase of $2400.

\n

Let $Hn represent Helen’s annual salary at the start of her nth year of employment.

\n
\n

At the start of each new year, Jane receives an annual salary increase of 3% of her previous year’s annual salary.

\n

Jane’s annual salary, $Jn, at the start of her nth year of employment is given by Jn=700001.03n-1.

\n
\n

At the start of year N, Jane’s annual salary exceeds Helen’s annual salary for the first time.

\n
\n

Show that Hn=2400n+67600.

\n
[2]
\n
a.
\n
\n

Given that Jn follows a geometric sequence, state the value of the common ratio, r.

\n
[1]
\n
b.
\n
\n

Find the value of N.

\n
[3]
\n
c.i.
\n
\n

For the value of N found in part (c) (i), state Helen’s annual salary and Jane’s annual salary, correct to the nearest dollar.

\n
[2]
\n
c.ii.
\n
\n

Find Jane’s total earnings at the start of her 10th year of employment. Give your answer correct to the nearest dollar.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

uses Hn=H1+n-1d with H1=70000 and d=2400       (M1)

\n

Hn=70000+2400n-1        A1

\n

so  Hn=2400n+67600         AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

r=1.03        A1

\n

 

\n

[1 mark]

\n
b.
\n
\n

evidence of use of an appropriate table or graph or GDC numerical solve feature to find the value of N such that Jn>Hn         (M1)

\n

 

\n

EITHER

\n

for example, an excerpt from an appropriate table

\n

        (A1)

\n

 

\n

OR

\n

for example, use of a GDC numerical solve feature to obtain N=10.800         (A1)

\n

 

\n

Note: Award A1 for an appropriate graph. Condone use of a continuous graph.

\n

 

\n

THEN

\n

N=11        A1

\n

 

\n

[3 marks]

\n
c.i.
\n
\n

H11=94000$        A1

\n

J11=94074$        A1

\n

Helen’s annual salary is $94000 and Jane’s annual salary is $94074

\n

 

\n

Note: Award A1 for a correct H11 value and A1 for a correct J11 value seen in part (c) (i).

\n

 

\n

[2 marks]

\n
c.ii.
\n
\n

at the start of the 10th year, Jane will have worked for 9 years so the value of S9 is required         R1

\n

 

\n

Note: Award R1 if S9 is seen anywhere.

\n

 

\n

uses Sn=J1rn-1r-1 with J1=70000r=1.03 and n=9        (M1)

\n

 

\n

Note: Award M1 if n=10 is used.

\n

 

\n

S9=700001.039-11.03-1=711137.42        (A1)

\n

=711137$

\n

Jane’s total earnings are $711137 (correct to the nearest dollar)

\n

 

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "EXN.2.SL.TZ0.7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Consider the function \nf\n, with derivative \n\nf\n\n\n\n(\nx\n)\n\n=\n2\n\n\nx\n2\n\n\n+\n5\nk\nx\n+\n3\n\n\nk\n2\n\n\n+\n2\n where \nx\n\n\n\nk\n\n\nR\n\n.

\n
\n

Show that the discriminant of  f ( x ) is k 2 16 .

\n
[2]
\n
a.
\n
\n

Given that f is an increasing function, find all possible values of k .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

correct substitution into  b 2 4 a c           (A1)

\n

eg     ( 5 k ) 2 4 ( 2 ) ( 3 k 2 + 2 ) ,   ( 5 k ) 2 8 ( 3 k 2 + 2 )

\n

correct expansion of each term         A1

\n

eg     25 k 2 24 k 2 16 ,   25 k 2 ( 24 k 2 + 16 )

\n

k 2 16         AG  N0

\n

[2 marks]

\n
a.
\n
\n

valid approach          M1

\n

eg     f ( x ) > 0 ,   f ( x ) 0

\n

recognizing discriminant  < 0 or  0           M1

\n

eg     D < 0 ,   k 2 16 0 ,   k 2 < 16

\n

two correct values for k /endpoints (even if inequalities are incorrect)          (A1)

\n

eg     k = ± 4 ,   k < 4   and  k > 4 ,   | k | < 4

\n

correct interval        A1  N2

\n

eg     4 < k < 4 ,   4 k 4

\n

Note: Candidates may work with an equation, then write the intervals with inequalities at the end. If inequalities are not seen until the candidate’s final correct answer, M0M0A1A1 may be awarded.
If candidate is working with incorrect inequalitie(s) at the beginning, then gets the correct final answer, award M0M0A1A0 or M1M0A1A0 or M0M1A1A0 in line with the markscheme.

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.1.SL.TZ0.S_5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

Consider the function f defined by f(x)=6+6cosx, for 0x4π.

\n

The following diagram shows the graph of y=f(x).

\n

\n

The graph of f touches the x-axis at points A and B, as shown. The shaded region is enclosed by the graph of y=f(x) and the x-axis, between the points A and B.

\n
\n

The right cone in the following diagram has a total surface area of 12π, equal to the shaded area in the previous diagram.

\n

The cone has a base radius of 2, height h, and slant height l.

\n

\n
\n

Find the x-coordinates of A and B.

\n
[3]
\n
a.
\n
\n

Show that the area of the shaded region is 12π.

\n
[5]
\n
b.
\n
\n

Find the value of l.

\n
[3]
\n
c.
\n
\n

Hence, find the volume of the cone.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

6+6cosx=0 (or setting their f'x=0)               (M1)

\n

cosx=-1 (or sinx=0)

\n

x=π, x=3π                  A1A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to integrate π3π6+6cosxdx               (M1)

\n

=6x+6sinxπ3π                  A1A1

\n

substitute their limits into their integrated expression and subtract               (M1)

\n

=18π+6sin3π-6π+6sinπ

\n

=63π+0-6π+0 =18π-6π                  A1

\n

area=12π                  AG

\n

 

\n

[5 marks]

\n
b.
\n
\n

attempt to substitute into formula for surface area (including base)               (M1)

\n

π22+π2l=12π               (A1)

\n

4π+2πl=12π

\n

2πl=8π

\n

l=4                  A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

valid attempt to find the height of the cone             (M1)

\n

e.g.  22+h2=their l2

\n

h=12 =23               (A1)

\n

attempt to use V=13πr2h with their values substituted             M1

\n

13π2212

\n

volume=4π123=8π33=8π3                  A1

\n

 

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21M.1.SL.TZ2.8", "topics": [ "topic-3-geometry-and-trigonometry", "topic-5-calculus" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations", "sl-5-10-indefinite-integration-reverse-chain-by-substitution", "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Consider the function fx=x2-x-122x-15, x, x152.

\n
\n

Find the coordinates where the graph of f crosses the

\n
\n

x-axis.

\n
[2]
\n
a.i.
\n
\n

y-axis.

\n
[1]
\n
a.ii.
\n
\n

Write down the equation of the vertical asymptote of the graph of f.

\n
[1]
\n
b.
\n
\n

The oblique asymptote of the graph of f can be written as y=ax+b where a, b.

\n

Find the value of a and the value of b.

\n
[4]
\n
c.
\n
\n

Sketch the graph of f for -30x30, clearly indicating the points of intersection with each axis and any asymptotes.

\n
[3]
\n
d.
\n
\n

Express 1fx in partial fractions.

\n
[3]
\n
e.i.
\n
\n

Hence find the exact value of 031fxdx, expressing your answer as a single logarithm.

\n
[4]
\n
e.ii.
\n
", "Markscheme": "
\n

Note: In part (a), penalise once only, if correct values are given instead of correct coordinates.

\n


attempts to solve x2-x-12=0              (M1)

\n

-3,0 and 4,0             A1

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

Note: In part (a), penalise once only, if correct values are given instead of correct coordinates.

\n

 

\n

0,45            A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

x=152            A1

\n


Note: Award A0 for x152.
          Award A1 in part (b), if x=152 is seen on their graph in part (d).

\n

[1 mark]

\n
b.
\n
\n

METHOD 1

\n

ax+b2x-15x2-x-12

\n

attempts to expand ax+b2x-15              (M1)

\n

2ax2-15ax+2bx-15bx2-x-12

\n

a=12            A1

\n

equates coefficients of x              (M1)

\n

-1=-152+2b

\n

b=134            A1

\n

y=x2+134

\n

 

\n

METHOD 2

\n

attempts division on x2-x-122x-15              M1

\n

x2+134+              M1

\n

a=12            A1

\n

b=134            A1

\n

y=x2+134

\n

 

\n

METHOD 3

\n

a=12            A1

\n

x2-x-122x-15x2+b+c2x-15              M1

\n

x2-x-122x-15x2+2x-15b+c

\n

equates coefficients of x :              (M1)

\n

-1=-152+2b

\n

b=134            A1

\n

y=x2+134

\n

 

\n

METHOD 4

\n

attempts division on x2-x-122x-15              M1

\n

x2-x-122x-15=x2+13x2-122x-15

\n

a=12            A1

\n

13x2-122x-15=134+              M1

\n

b=134            A1

\n

y=x2+134

\n

 

\n

[4 marks]

\n
c.
\n
\n

 

\n

two branches with approximately correct shape (for -30x30)            A1

\n

their vertical and oblique asymptotes in approximately correct positions with both branches showing correct asymptotic behaviour to these asymptotes            A1

\n

their axes intercepts in approximately the correct positions            A1

\n


Note: Points of intersection with the axes and the equations of asymptotes are not required to be labelled.

\n

 

\n

[3 marks]

\n
d.
\n
\n

attempts to split into partial fractions:             (M1)

\n

2x-15x+3x-4Ax+3+Bx-4

\n

2x-15Ax-4+Bx+3

\n

A=3             A1

\n

B=-1             A1

\n

3x+3-1x-4

\n

 

\n

[3 marks]

\n
e.i.
\n
\n

033x+3-1x-4dx

\n

attempts to integrate and obtains two terms involving ‘ln’             (M1)

\n

=3lnx+3-lnx-403             A1

\n

=3ln6-ln1-3ln3+ln4             A1

\n

=3ln2+ln4  =ln8+ln4

\n

=ln32  =5ln2             A1

\n


Note: The final A1 is dependent on the previous two A marks.

\n

 

\n

[4 marks]

\n
e.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
", "question_id": "21N.2.AHL.TZ0.10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-7-laws-of-exponents-and-logs" ] }, { "Question": "
\n

Let  f ( x ) = 4 cos ( x 2 ) + 1 , for  0 x 6 π . Find the values of x for which f ( x ) > 2 2 + 1 .

\n
", "Markscheme": "
\n

METHOD 1 – FINDING INTERVALS FOR x

\n

4 cos ( x 2 ) + 1 > 2 2 + 1

\n

correct working          (A1)

\n

eg    4cosx2=22,  cosx2>22

\n

recognizing   co s 1 2 2 = π 4           (A1)

\n

one additional correct value for x 2 (ignoring domain and equation/inequalities)          (A1)

\n

eg     π 4 7 π 4 315 9 π 4 45 15 π 4

\n

three correct values for x         A1A1

\n

eg     π 2 7 π 2 9 π 2

\n

valid approach to find intervals          (M1)

\n

eg    

\n

correct intervals (must be in radians)        A1A1     N2

\n

0 x < π 2 7 π 2 < x < 9 π 2  

\n

Note: If working shown, award A1A0 if inclusion/exclusion of endpoints is incorrect. If no working shown award N1.
If working shown, award A1A0 if both correct intervals are given, and additional intervals are given. If no working shown award N1.
Award A0A0 if inclusion/exclusion of endpoints are incorrect and additional intervals are given.

\n

 

\n

METHOD 2 – FINDING INTERVALS FOR  x 2

\n

4cosx2+1>22+1

\n

correct working          (A1)

\n

eg    4cosx2=22,  cosx2>22

\n

recognizing   co s 1 2 2 = π 4           (A1)

\n

one additional correct value for x 2 (ignoring domain and equation/inequalities)          (A1)

\n

eg     π 4 7 π 4 315 9 π 4 45 15 π 4

\n

three correct values for x 2        A1

\n

eg     π 4 7 π 4 9 π 4

\n

valid approach to find intervals          (M1)

\n

eg   

\n

one correct interval for  x 2         A1

\n

eg     0 x 2 < π 4 7 π 4 < x 2 < 9 π 4

\n

correct intervals (must be in radians)        A1A1     N2

\n

0 x < π 2 7 π 2 < x < 9 π 2  

\n

Note: If working shown, award A1A0 if inclusion/exclusion of endpoints is incorrect. If no working shown award N1.
If working shown, award A1A0 if both correct intervals are given, and additional intervals are given. If no working shown award N1.
Award A0A0 if inclusion/exclusion of endpoints are incorrect and additional intervals are given.

\n

 

\n

[8 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.1.SL.TZ0.S_6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-8-solving-trig-equations" ] }, { "Question": "
\n

Let \nX\n and \nY\n be normally distributed with \nX\n\n\nN\n\n\n(\n\n14\n\n\n\n\n\na\n2\n\n\n\n)\n\n and \nY\n\n\nN\n\n\n(\n\n22\n\n\n\n\n\na\n2\n\n\n\n)\n\n\na\n>\n0\n.

\n
\n

Find b so that  P ( X > b ) = P ( Y < b ) .

\n
[2]
\n
a.
\n
\n

It is given that  P ( X > 20 ) = 0.112 .

\n

Find P ( 16 < Y < 28 ) .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

recognizing that b is midway between the means of 14 and 22 .          (M1)

\n

eg    b = 14 + 22 2

\n

b = 18         A1   N2

\n

 

\n

METHOD 2

\n

valid attempt to compare distributions          (M1)

\n

eg     b 14 a = b 22 a b 14 = 22 b

\n

b = 18         A1   N2

\n

 

\n

[2 marks]

\n
a.
\n
\n

valid attempt to compare distributions (seen anywhere)       (M1)

\n

eg    Y is a horizontal translation of X of 8 units to the right,

\n

P ( 16 < Y < 28 ) = P ( 8 < X < 20 ) , P ( Y > 22 + 6 ) = P ( X > 14 + 6 )

\n

valid approach using symmetry       (M1)

\n

eg   12P(X>20)12P(Y<16)2×P(14<x<20), P(X<8)=P(X>20)

\n

correct working          (A1)

\n

eg    1 2 ( 0.112 ) 2 × ( 0.5 0.112 ) 2 × 0.388 0.888 0.112

\n

P ( 16 < Y < 28 ) = 0.776         A1   N3

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.1.SL.TZ0.S_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Particle A travels in a straight line such that its displacement, s metres, from a fixed origin after t seconds is given by s(t)=8t-t2, for 0t10, as shown in the following diagram.

\n

\n

Particle A starts at the origin and passes through the origin again when t=p.

\n
\n

Particle A changes direction when t=q.

\n
\n

The total distance travelled by particle A is given by d.

\n
\n

Find the value of p.

\n
[2]
\n
a.
\n
\n

Find the value of q.

\n
[2]
\n
b.i.
\n
\n

Find the displacement of particle A from the origin when t=q.

\n
[2]
\n
b.ii.
\n
\n

Find the distance of particle A from the origin when t=10.

\n
[2]
\n
c.
\n
\n

Find the value of d.

\n
[2]
\n
d.
\n
\n

A second particle, particle B, travels along the same straight line such that its velocity is given by v(t)=14-2t, for t0.

\n

When t=k, the distance travelled by particle B is equal to d.

\n

Find the value of k.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

setting st=0            (M1)

\n

8t-t2=0

\n

t8-t=0

\n

p=8  (accept t=8, 8,0)                 A1

\n

 

\n

Note: Award A0 if the candidate’s final answer includes additional solutions (such as p=0,8).

\n

 

\n

[2 marks]

\n
a.
\n
\n

recognition that when particle changes direction v=0 OR local maximum on graph of s OR vertex of parabola            (M1)

\n

q=4 (accept t=4)            A1

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

substituting their value of q into st OR integrating vt from t=0 to t=4             (M1)

\n

displacement=16(m)         A1

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

s10=-20  OR  distance=st OR integrating vt from t=0 to t=10             (M1)

\n

distance=20(m)        A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

16 forward + 36 backward  OR  16+16+20  OR  010vtdt             (M1)

\n

d=52m        A1

\n

 

\n

[2 marks]

\n
d.
\n
\n

METHOD 1

\n

graphical method with triangles on vt graph             M1

\n

49+x2x2             (A1)

\n

49+x2=52, x=3             (A1)

\n

k=7+3        A1

\n

 

\n

METHOD 2

\n

recognition that distance =vtdt             M1

\n

0714-2tdt+7k2t-14dt

\n

14t-t207+t2-14t7k             (A1)

\n

147-72+k2-14k-72-147=52             (A1)

\n

k=7+3        A1

\n

 

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.1.SL.TZ2.9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

A small cuboid box has a rectangular base of length \n3\nx\n cm and width \nx\n cm, where \nx\n>\n0\n. The height is \ny\n cm, where \ny\n>\n0\n.

\n

\n

The sum of the length, width and height is \n12\n cm.

\n
\n

The volume of the box is \nV\n cm3.

\n
\n

Write down an expression for y in terms of x .

\n
[1]
\n
a.
\n
\n

Find an expression for V in terms of x .

\n
[2]
\n
b.
\n
\n

Find d V d x .

\n
[2]
\n
c.
\n
\n

Find the value of x for which V is a maximum.

\n
[4]
\n
d.i.
\n
\n

Justify your answer.

\n
[3]
\n
d.ii.
\n
\n

Find the maximum volume.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

y = 12 4 x         A1   N1

\n

[1 mark]

\n
a.
\n
\n

correct substitution into volume formula        (A1)

\n

eg     3 x × x × y x × 3 x × ( 12 x 3 x ) ( 12 4 x ) ( x ) ( 3 x )

\n

V = 3 x 2 ( 12 4 x ) ( = 36 x 2 12 x 3 )        A1   N2

\n

Note: Award A0 for unfinished answers such as 3 x 2 ( 12 x 3 x ) .

\n

[2 marks]

\n
b.
\n
\n

d V d x = 72 x 36 x 2            A1A1   N2

\n

Note: Award A1 for 72 x and A1 for 36 x 2 .

\n

[2 marks]

\n
c.
\n
\n

valid approach to find maximum           (M1)

\n

eg       V = 0 72 x 36 x 2 = 0

\n

correct working           (A1)

\n

eg       x ( 72 36 x ) 72 ± 72 2 4 ( 36 ) 0 2 ( 36 ) 36 x = 72 36 x ( 2 x ) = 0

\n

x = 2            A2   N2

\n

Note: Award A1 for  x = 2 and x = 0 .

\n

[4 marks]

\n
d.i.
\n
\n

valid approach to explain that V is maximum when  x = 2         (M1)

\n

eg      attempt to find V , sign chart (must be labelled V )

\n

correct value/s         A1

\n

eg       V ( 2 ) = 72 72 × 2 ,   V ( a )   where  a < 2   and   V ( b ) where   b > 2

\n

correct reasoning         R1

\n

eg       V ( 2 ) < 0 ,   V   is positive for  x < 2   and negative for  x > 2

\n

Note: Do not award R1 unless A1 has been awarded.

\n

V is maximum when  x = 2            AG   N0

\n

[3 marks]

\n
d.ii.
\n
\n

correct substitution into their expression for volume        A1

\n

eg      3 × 2 2 ( 12 4 × 2 ) ,   36 ( 2 2 ) 12 ( 2 3 )

\n

V = 48 (cm3)           A1   N1

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "19N.1.SL.TZ0.S_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

The time, T minutes, taken to complete a jigsaw puzzle can be modelled by a normal distribution with mean μ and standard deviation 8.6.

\n

It is found that 30% of times taken to complete the jigsaw puzzle are longer than 36.8 minutes.

\n
\n

Use μ=32.29 in the remainder of the question.

\n
\n

Six randomly chosen people complete the jigsaw puzzle.

\n
\n

By stating and solving an appropriate equation, show, correct to two decimal places, that μ=32.29.

\n
[4]
\n
a.
\n
\n

Find the 86th percentile time to complete the jigsaw puzzle.

\n
[2]
\n
b.
\n
\n

Find the probability that a randomly chosen person will take more than 30 minutes to complete the jigsaw puzzle.

\n
[2]
\n
c.
\n
\n

Find the probability that at least five of them will take more than 30 minutes to complete the jigsaw puzzle.

\n
[3]
\n
d.
\n
\n

Having spent 25 minutes attempting the jigsaw puzzle, a randomly chosen person had not yet completed the puzzle.

\n

Find the probability that this person will take more than 30 minutes to complete the jigsaw puzzle.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

T~Nμ,8.62

\n

PT36.8=0.7        (A1)

\n

states a correct equation, for example, 36.8-μ8.6=0.5244        A1

\n

attempts to solve their equation        (M1)

\n

μ=36.8-0.52448.6  =32.2902        A1

\n

the solution to the equation is μ=32.29, correct to two decimal places        AG

\n

 

\n

[4 marks]

\n
a.
\n
\n

let t0.86 be the 86th percentile

\n

attempts to use the inverse normal feature of a GDC to find t0.86       (M1)

\n

t0.86=41.6 (mins)        A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

evidence of identifying the correct area under the normal curve         (M1)

\n

Note: Award M1 for a clearly labelled sketch.

\n

PT>30=0.605         A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

let X represent the number of people out of the six who take more than 30 minutes to complete the jigsaw puzzle

\n

X~B6,0.6049         (M1)

\n

for example, PX=5+PX=6 or 1-PX4         (A1)

\n

PX5=0.241         A1

\n

 

\n

[3 marks]

\n
d.
\n
\n

recognizes that PT>30 T25 is required         (M1)

\n

 

\n

Note: Award M1 for recognizing conditional probability.

\n

 

\n

=PT>30T25PT25         (A1)

\n

=PT>30PT25=0.60490.8016         M1

\n

=0.755         A1

\n

 

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "EXN.2.SL.TZ0.8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations", "sl-4-8-binomial-distribution", "sl-4-11-conditional-and-independent-probabilities-test-for-independence" ] }, { "Question": "
\n

Three points A3, 0, 0, B0, -2, 0 and C1, 1, -7 lie on the plane Π1.

\n
\n

Plane Π2 has equation 3x-y+2z=2.

\n
\n

The plane Π3 is given by 2x-2z=3. The line L and the plane Π3 intersect at the point P.

\n
\n

The point B(0,-2, 0) lies on L.

\n
\n

Find the vector AB and the vector AC.

\n
[2]
\n
a.i.
\n
\n

Hence find the equation of Π1, expressing your answer in the form ax+by+cz=d, where a, b, c, d.

\n
[5]
\n
a.ii.
\n
\n

The line L is the intersection of Π1 and Π2. Verify that the vector equation of L can be written as r=0-20+λ11-1.

\n
[2]
\n
b.
\n
\n

Show that at the point P, λ=34.

\n
[2]
\n
c.i.
\n
\n

Hence find the coordinates of P.

\n
[1]
\n
c.ii.
\n
\n

Find the reflection of the point B in the plane Π3.

\n
[7]
\n
d.i.
\n
\n

Hence find the vector equation of the line formed when L is reflected in the plane Π3.

\n
[2]
\n
d.ii.
\n
", "Markscheme": "
\n

attempts to find either AB or AC             (M1)

\n

AB=-3-20 and AC=-21-7             A1

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

METHOD 1

\n

attempts to find AB×AC             (M1)

\n

AB×AC=14-21-7             A1

\n


EITHER

\n

equation of plane is of the form 14x-21y-7z=d   2x-3y-z=d               (A1)

\n

substitutes a valid point e.g 3, 0, 0 to obtain a value of d             M1

\n

d=42  d=6

\n


OR

\n

attempts to use r·n=a·n             (M1)

\n

r·14-21-7=300·14-21-7  r·14-21-7=42               A1

\n

r·2-3-1=300·2-3-1  r·2-3-1=6

\n


THEN

\n

14x-21y-7z=42  2x-3y-z=6               A1

\n

 

\n

METHOD 2

\n

equation of plane is of the form xyz=300+s-3-20+t-21-7               A1

\n

attempts to form equations for x, y, z in terms of their parameters             (M1)

\n

x=3-3s-2t , y=-2s+t , z=-7t               A1

\n

eliminates at least one of their parameters             (M1)

\n

for example, 2x-3y=6-7t2x-3y=6+z

\n

2x-3y-z=6               A1

\n

 

\n

[5 marks]

\n
a.ii.
\n
\n

METHOD 1

\n

substitutes r=0-20+λ11-1 into their Π1 and Π2 (given)             (M1)

\n

Π1: 2λ-3-2+λ--λ=6  and  Π2: 3λ-3-2+λ+2-λ=2            A1

\n


Note: Award (M1)A0 for correct verification using a specific value of λ.

\n

so the vector equation of L can be written as r=0-20+λ11-1            AG

\n


METHOD 2

\n

EITHER

\n

attempts to find  2-3-1×3-12                    M1

\n

=-7-77

\n


OR

\n

2-3-1·11-1=2-3+1=0  and  3-12·11-1=3-1-2=0                    M1

\n


THEN

\n

substitutes 0,-2,0 into Π1 and Π2

\n

Π1: 20-3-2-0=6  and  Π2: 30--2+20=2            A1

\n

so the vector equation of L can be written as r=0-20+λ11-1            AG

\n

 

\n

METHOD 3

\n

attempts to solve 2x-3y-z=6 and 3x-y+2z=2             (M1)

\n

for example, x=-λ, y=-2-λ, z=λ               A1

\n


Note: Award A1 for substituting x=0 (or y=-2 or z=0) into Π1 and Π2 and solving simultaneously. For example, solving -3y-z=6 and -y+2z=2 to obtain y=-2 and z=0.

\n

so the vector equation of L can be written as r=0-20+λ11-1            AG

\n

 

\n

[2 marks]

\n
b.
\n
\n

substitutes the equation of L into the equation of Π3             (M1)

\n

2λ+2λ=34λ=3            A1

\n

λ=34            AG

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

P has coordinates  34,-54,-34       A1

\n

 

\n

[1 mark]

\n
c.ii.
\n
\n

normal to Π3 is n=20-2               (A1)

\n


Note: May be seen or used anywhere.

\n


considers the line normal to Π3 passing through B0,-2,0               (M1)
r=0-20+μ20-2                A1

\n


EITHER

\n

finding the point on the normal line that intersects Π3
attempts to solve simultaneously with plane 2x-2z=3               (M1)

\n

4μ+4μ=3

\n

μ=38                A1

\n

point is 34, -2,-34

\n


OR

\n

2μ-2-2μ-34-54-34·20-2=0               (M1)

\n

4μ-32+4μ-32=0

\n

μ=38               A1

\n


OR

\n

attempts to find the equation of the plane parallel to Π3 containing B' x-z=3 and solve simultaneously with L               (M1)

\n

2μ'+2μ'=3

\n

μ'=34               A1

\n


THEN

\n

so, another point on the reflected line is given by

\n

r=0-20+3420-2               (A1)

\n

B'32,-2,-32               A1

\n

 

\n

[7 marks]

\n
d.i.
\n
\n

EITHER

\n

attempts to find the direction vector of the reflected line using their P and B'               (M1)

\n

PB'=34-34-34

\n


OR

\n

attempts to find their direction vector of the reflected line using a vector approach               (M1)

\n

PB'=PB+BB'=-3411-1+3210-1

\n


THEN

\n

r=32-2-32+λ34-34-34 (or equivalent)                A1

\n


Note:
Award A0 for either 'r=' or 'xyz=' not stated. Award A0 for 'L'='

\n

 

\n

[2 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "21N.2.AHL.TZ0.11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

Solve the equation 2cos2x+5sinx=4, 0x2π.

\n
", "Markscheme": "
\n

attempt to use cos2x=1-sin2x              M1

\n

2sin2x-5sinx+2=0                   A1

\n

 

\n

EITHER

\n

attempting to factorise              M1

\n

(2sinx1)(sinx2)                   A1

\n

 

\n

OR

\n

attempting to use the quadratic formula            M1

\n

sinx=5±52-4×2×24=5±34         A1

\n

 

\n

THEN

\n

sinx=12           (A1)

\n

x=π6,5π6                  A1A1

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.AHL.TZ2.2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-8-solving-trig-equations" ] }, { "Question": "
\n

Given any two non-zero vectors, a and b, show that a×b2=a2b2-a·b2.

\n
", "Markscheme": "
\n

METHOD 1

\n

use of a×b=absinθ on the LHS            (M1)

\n

a×b2=a2b2sin2θ                   A1

\n

=a2b21-cos2θ            M1

\n

=a2b2-a2b2cos2θ  OR  =a2b2-abcosθ2                   A1

\n

=a2b2-a·b2                   AG

\n

 

\n

METHOD 2

\n

use of a·b=abcosθ on the RHS            (M1)

\n

=a2b2-a2b2cos2θ                   A1

\n

=a2b21-cos2θ            M1

\n

=a2b2sin2θ  OR  =absinθ2                   A1

\n

=a×b2                   AG

\n

 

\n

Note: If candidates attempt this question using cartesian vectors, e.g

\n

a=a1a2a3  and  b=b1b2b3,

\n

award full marks if fully developed solutions are seen.
Otherwise award no marks.

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.AHL.TZ2.5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The temperature T°C of water t minutes after being poured into a cup can be modelled by T=T0e-kt where t0 and T0,k are positive constants.

\n

The water is initially boiling at 100°C. When t=10, the temperature of the water is 70°C.

\n
\n

Show that T0=100.

\n
[1]
\n
a.
\n
\n

Show that k=110ln107.

\n
[3]
\n
b.
\n
\n

Find the temperature of the water when t=15.

\n
[2]
\n
c.
\n
\n

Sketch the graph of T versus t, clearly indicating any asymptotes with their equations and stating the coordinates of any points of intersection with the axes.

\n
[4]
\n
d.
\n
\n

Find the time taken for the water to have a temperature of 50°C. Give your answer correct to the nearest second.

\n
[4]
\n
e.
\n
\n

The model for the temperature of the water can also be expressed in the form T=T0at10 for t0 and a is a positive constant.

\n

Find the exact value of a.

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

when t=0, T=100100=T0e0         A1

\n

so T0=100         AG

\n

 

\n

[1 mark]

\n
a.
\n
\n

correct substitution of t=10, T=70         M1

\n

70=100e-10k  or  e-10k=710

\n

 

\n

EITHER

\n

-10k=ln710         A1

\n

ln710=-ln107  or  -ln710=ln107         A1

\n

 

\n

OR

\n

e10k=107         A1

\n

10k=ln107         A1

\n

 

\n

THEN

\n

k=110ln107         AG

\n

 

\n

[3 marks]

\n
b.
\n
\n

substitutes t=15 into T         (M1)

\n

T=58.6°C         A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

\n

a decreasing exponential         A1

\n

starting at 0,100 labelled on the graph or stated         A1

\n

T0 as t         A1

\n

horizontal asymptote T=0 labelled on the graph or stated         A1

\n

 

\n

Note: Award A0 for stating y=0 as the horizontal asymptote.

\n

 

\n

[4 marks]

\n
d.
\n
\n

100e-kt=50  where k=110ln107        A1

\n

 

\n

EITHER

\n

uses an appropriate graph to attempt to solve for t         (M1)

\n

 

\n

OR

\n

manipulates logs to attempt to solve for t e.g. ln12=-110ln107t         (M1)

\n

t=ln2110ln107=19.433        A1

\n

 

\n

THEN

\n

temperature will be 50°C after 19 minutes and 26 seconds        A1

\n

 

\n

[4 marks]

\n
e.
\n
\n

METHOD 1

\n

substitutes T0=100t=10 and T=70 into T=T0at10         (M1)

\n

70=100a1010        A1

\n

a=710        A1

\n

 

\n

METHOD 2

\n

100at10=100e-kt  where k=110ln107

\n

 

\n

EITHER

\n

e-k=a110a=e-10k         (M1)

\n

 

\n

OR

\n

a=e-110ln107t10t         (M1)

\n

 

\n

THEN

\n

a=e-ln107 =eln710        A1

\n

a=710        A1

\n

 

\n

[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "EXN.2.SL.TZ0.9", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-9-exponential-and-logarithmic-functions", "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

The cubic equation x3-kx2+3k=0 where k>0 has roots α, β and α+β.

\n

Given that αβ=-k24, find the value of k.

\n
", "Markscheme": "
\n

α+β+α+β=k           (A1)

\n

α+β=k2

\n

αβα+β=-3k           (A1)

\n

-k24k2=-3k  -k38=-3k           M1

\n

attempting to solve -k38+3k=0 (or equivalent) for k           (M1)

\n

k=26 =24k>0                 A1

\n

 

\n

Note: Award A0 for k=±26 ±24.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.AHL.TZ2.7", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

The lines l1 and l2 have the following vector equations where λ, μ.

\n

l1:r1=32-1+λ2-22

\n

l2:r2=204+μ1-11

\n
\n

Show that l1 and l2 do not intersect.

\n
[3]
\n
a.
\n
\n

Find the minimum distance between l1 and l2.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

setting at least two components of l1 and l2 equal           M1

\n

3+2λ=2+μ      1

\n

2-2λ=-μ        2

\n

-1+2λ=4+μ  3

\n

attempt to solve two of the equations eg. adding 1 and 2           M1

\n

gives a contradiction (no solution), eg 5=2           R1

\n

so l1 and l2 do not intersect                   AG

\n

 

\n

Note: For an error within the equations award M0M1R0.
Note: The contradiction must be correct to award the R1.

\n

 

\n

METHOD 2

\n

l1 and l2 are parallel, so l1 and l2 are either identical or distinct.           R1

\n

Attempt to subtract two position vectors from each line,

\n

e.g. 32-1-204=12-5           M1

\n

32-1k1-11               A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

l1 and l2 are parallel (as 2-22 is a multiple of 1-11)

\n

let A be 3,2,-1 on l1 and let B be 2,0,4 on l2

\n

Attempt to find vector AB=-1-25            (M1)

\n

Distance required is v×ABv              M1

\n

=131-11×-1-25            (A1)

\n

=13363                    A1

\n

minimum distance is 18=32                    A1

\n

 

\n

METHOD 2

\n

l1 and l2 are parallel (as 2-22 is a multiple of 1-11)

\n

let A be a fixed point on l1 eg 3,2,-1 and let B be a general point on l2 2+μ,-μ,4+μ

\n

attempt to find vector AB            (M1)

\n

AB=-1-25+μ1-11 μ                   A1

\n

AB=-1+μ2+-2-μ2+5+μ2 =3μ2+12μ+30              M1

\n


EITHER

\n

null                   A1

\n


OR

\n

AB=3μ+22+18 to obtain μ=-2                   A1

\n


THEN

\n

minimum distance is 18=32                   A1

\n

 

\n

METHOD 3

\n

let A be 3,2,-1 on l1 and let B be 2+μ,-μ,4+μ on l2              (M1)

\n

(or let A be 2,0,4 on l2 and let B be 3+2λ,2-2λ,-1+2λ on l1)

\n

AB=-1-25+μ1-11 μ  (or AB=2λ+1-2λ+22λ-5)                 A1

\n

μ-1-μ-2μ+5·1-11=0  (or 2λ+1-2λ+22λ-5·1-11=0)              M1

\n

μ=-2  or  λ=1                   A1

\n

minimum distance is 18=32                   A1

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.AHL.TZ2.8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The points \n\nA\n\n and \n\nB\n\n have position vectors \n\n(\n\n\n\n\n\n\n2\n\n\n\n\n\n4\n\n\n\n\n\n\n4\n\n\n\n\n\n)\n\n and \n\n(\n\n\n\n\n6\n\n\n\n\n8\n\n\n\n\n0\n\n\n\n\n)\n\n respectively.

\n

Point \n\nC\n\n has position vector \n\n(\n\n\n\n\n\n\n1\n\n\n\n\n\nk\n\n\n\n\n0\n\n\n\n\n)\n\n. Let \n\nO\n\n be the origin.

\n
\n

Find, in terms of \nk\n,

\n
\n

OA OC .

\n
[2]
\n
a.i.
\n
\n

OB OC .

\n
[1]
\n
a.ii.
\n
\n

Given that  A O ^ C = B O ^ C , show that k = 7 .

\n
[8]
\n
b.
\n
\n

Calculate the area of triangle  AOC .

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

correct substitution into either  OA OC or into  OB OC (in (ii))          (A1)     

\n

eg       2 × ( 1 ) + 4 × k ,   6 × ( 1 ) + 8 × k

\n

correct expression           A1   N1

\n

eg       2 + 4 k ,   4 k + 2

\n

[2 marks]

\n
a.i.
\n
\n

correct expression           A1   N1

\n

eg       8 k 6 ,   6 + 8 k

\n

[1 mark]

\n
a.ii.
\n
\n

finding magnitudes (seen anywhere)           A1A1

\n

eg       ( 2 ) 2 + ( 4 ) 2 + ( 4 ) 2 ( = 6 ) ,   ( 6 ) 2 + ( 8 ) 2 + 0 2 ( = 10 )

\n

correct substitution of their values into formula for angle  AOC            (A1)

\n

eg       cos θ = 2 + 4 k ( 2 ) 2 + ( 4 ) 2 + ( 4 ) 2 | OC |

\n

correct substitution of their values into formula for angle BOC            (A1)

\n

eg       cos θ = 8 k 6 ( 6 ) 2 + ( 8 ) 2 + 0 2 | OC |

\n

recognizing that  cos A O ^ C = cos B O ^ C   (seen anywhere)           (M1)

\n

eg       2 + 4 k | OC | ( 2 ) 2 + ( 4 ) 2 + ( 4 ) 2 = 8 k 6 | OC | 6 2 + ( 8 ) 2 + 0 2 ,   2 + 4 k 6 1 + k 2 = 8 k 6 10 1 + k 2

\n

correct working (without radicals)           (A2)

\n

eg       10 ( 2 + 4 k ) = 6 ( 8 k 6 ) ,   11 k 2 79 k + 14 = 0

\n

correct working clearly leading to the required answer           A1

\n

eg      20+36=48k-40k,   56 = 8 k ,   k = 7   and   k = 2 11 ,   ( k 7 ) ( 11 k 2 ) = 0

\n

k = 7            AG   N0

\n

[8 marks]

\n
b.
\n
\n

finding magnitude of  OC (seen anywhere)           A1

\n

eg       ( 1 ) 2 + 7 2 + 0 2 ,   50

\n

valid attempt to find  cos θ            (M1)

\n

eg       cos θ = 2 + 28 6 ( 1 ) 2 + 7 2 + 0 2 ,   cos θ = 56 6 10 ( 1 ) 2 + 7 2 + 0 2 ,   ( 26 ) 2 = 6 2 + ( 50 ) 2 2 ( 6 ) 50 cos θ

\n

finding cos θ            A1

\n

eg       cos θ = 5 50 ( = 1 2 )

\n

valid approach to find sin θ (seen anywhere)           (M1)

\n

eg       θ = π 4 ,   sin θ = cos θ ,   sin θ = 1 25 50 ,   sin θ = 1 co s 2 θ ,   sin θ = 2 2

\n

correct substitution of their values into  1 2 a b sin C            (A1)

\n

eg      12×6×50×1-2550,   1 2 × 6 × 50 × 5 50

\n

area is 15            A1   N3

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.1.SL.TZ0.S_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

In this question you will explore some of the properties of special functions f and g and their relationship with the trigonometric functions, sine and cosine.

\n


Functions f and g are defined as fz=ez+e-z2 and gz=ez-e-z2, where z.

\n

Consider t and u, such that t, u.

\n
\n

Using eiu=cosu+isinu, find expressions, in terms of sinu and cosu, for

\n
\n

The functions cosx and sinx are known as circular functions as the general point (cosθ, sinθ) defines points on the unit circle with equation x2+y2=1.

\n

The functions f(x) and g(x) are known as hyperbolic functions, as the general point ( f(θ), g(θ) ) defines points on a curve known as a hyperbola with equation x2-y2=1. This hyperbola has two asymptotes.

\n
\n

Verify that u=ft satisfies the differential equation d2udt2=u.

\n
[2]
\n
a.
\n
\n

Show that ft2+gt2=f2t.

\n
[3]
\n
b.
\n
\n

fiu.

\n
[3]
\n
c.i.
\n
\n

giu.

\n
[2]
\n
c.ii.
\n
\n

Hence find, and simplify, an expression for fiu2+giu2.

\n
[2]
\n
d.
\n
\n

Show that ft2-gt2=fiu2-giu2.

\n
[4]
\n
e.
\n
\n

Sketch the graph of x2-y2=1, stating the coordinates of any axis intercepts and the equation of each asymptote.

\n
[4]
\n
f.
\n
\n

The hyperbola with equation x2-y2=1 can be rotated to coincide with the curve defined by xy=k, k.

\n

Find the possible values of k.

\n
[5]
\n
g.
\n
", "Markscheme": "
\n

f't=et-e-t2                       A1

\n

f''t=et+e-t2                       A1

\n

=ft                       AG

\n


[2 marks]

\n
a.
\n
\n

METHOD 1

\n

ft2+gt2

\n

substituting f and g                      M1

\n

=et+e-t2+et-e-t24

\n

=et2+2+e-t2+et2-2+e-t24                      (M1)

\n

=et2+e-t22  =e2t+e-2t2                      A1

\n

=f2t                      AG

\n

 

\n

METHOD 2

\n

f2t=e2t+e-2t2

\n

=et2+e-t22                      M1

\n

=et+e-t2+et-e-t24                     M1A1

\n

=ft2+gt2                      AG

\n


Note: Accept combinations of METHODS 1 & 2 that meet at equivalent expressions.

\n


[3 marks]

\n
b.
\n
\n

substituting eiu=cosu+isinu into the expression for f                      (M1)

\n

obtaining e-iu=cosu-isinu                      (A1)

\n

fiu=cosu+isinu+cosu-isinu2

\n


Note: The M1 can be awarded for the use of sine and cosine being odd and even respectively.

\n


=2cosu2

\n

=cosu                      A1

\n


[3 marks]

\n
c.i.
\n
\n

giu=cosu+isinu-cosu+isinu2

\n

substituting and attempt to simplify                      (M1)

\n

=2isinu2

\n

=isinu                      A1

\n


[2 marks]

\n
c.ii.
\n
\n

METHOD 1

\n

fiu2+giu2

\n

substituting expressions found in part (c)                     (M1)

\n

=cos2u-sin2u  =cos2u                      A1

\n

 

\n

METHOD 2

\n

f2iu=e2iu+e-2iu2

\n

=cos2u+isin2u+cos2u-isin2u2                     M1

\n

=cos2u                      A1

\n


Note: Accept equivalent final answers that have been simplified removing all imaginary parts eg 2cos2u1etc

\n


[2 marks]

\n
d.
\n
\n

ft2-gt2=et+e-t2-et-e-t24                      M1

\n

=e2t+e-2t+2-e2t+e-2t-24                      A1

\n

=44=1                      A1

\n


Note: Award A1 for a value of 1 obtained from either LHS or RHS of given expression.

\n


fiu2-giu2=cos2u+sin2u                      M1

\n

=1  (hence ft2-gt2=fiu2-giu2)                      AG

\n


Note: Award full marks for showing that fz2-gz2=1, z.


[4 marks]

\n
e.
\n
\n

        A1A1A1A1

\n


Note: Award A1 for correct curves in the upper quadrants, A1 for correct curves in the lower quadrants, A1 for correct x-intercepts of (1, 0) and (1, 0) (condone x=1 and 1), A1 for y=x and y=x.

\n



[4 marks]

\n
f.
\n
\n

attempt to rotate by 45° in either direction               (M1)

\n


Note: Evidence of an attempt to relate to a sketch of xy=k would be sufficient for this (M1).

\n


attempting to rotate a particular point, eg (1, 0)               (M1)

\n

(1, 0) rotates to 12,±12 (or similar)               (A1)

\n

hence k=±12             A1A1

\n


[5 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "21N.3.AHL.TZ0.1", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing" ] }, { "Question": "
\n

The acceleration, ams-2, of a particle moving in a horizontal line at time t seconds, t0, is given by a=-(1+v) where vms-1 is the particle’s velocity and v>-1.

\n

At t=0, the particle is at a fixed origin O and has initial velocity v0ms-1.

\n
\n

Initially at O, the particle moves in the positive direction until it reaches its maximum displacement from O. The particle then returns to O.

\n

Let s metres represent the particle’s displacement from O and smax its maximum displacement from O.

\n
\n

Let v(T-k) represent the particle’s velocity k seconds before it reaches smax, where

\n

v(T-k)=1+v0e-(T-k)-1.

\n
\n

Similarly, let v(T+k) represent the particle’s velocity k seconds after it reaches smax.

\n
\n

By solving an appropriate differential equation, show that the particle’s velocity at time t is given by v(t)=(1+v0)e-t-1.

\n
[6]
\n
a.
\n
\n

Show that the time T taken for the particle to reach smax satisfies the equation eT=1+v0.

\n
[2]
\n
b.i.
\n
\n

By solving an appropriate differential equation and using the result from part (b) (i), find an expression for smax in terms of v0.

\n
[5]
\n
b.ii.
\n
\n

By using the result to part (b) (i), show that vT-k=ek-1.

\n
[2]
\n
c.
\n
\n

Deduce a similar expression for v(T+k) in terms of k.

\n
[2]
\n
d.
\n
\n

Hence, show that vT-k+vT+k0.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

dvdt=-1+v         (A1)

\n

1dt=-11+vdv  (or equivalent / use of integrating factor)        M1

\n

t=-ln1+v+C        A1

\n

 

\n

EITHER

\n

attempt to find C with initial conditions t=0, v=v0        M1

\n

C=ln1+v0

\n

t=ln1+v0-ln1+v

\n

t=ln1+v01+vet=1+v01+v        A1

\n

et1+v=1+v0

\n

1+v=1+v0e-t        A1

\n

vt=1+v0e-t-1        AG

\n

 

\n

OR

\n

t-C=-ln1+vet-C=11+v

\n

Attempt to find C with initial conditions t=0, v=v0        M1

\n

e-C=11+v0C=ln1+v0

\n

t-ln1+v0=-ln1+vt=ln1+v0-ln1+v

\n

t=ln1+v01+vet=1+v01+v        A1

\n

et1+v=1+v0

\n

1+v=1+v0e-t        A1

\n

vt=1+v0e-t-1        AG

\n

 

\n

OR

\n

t-C=-ln1+ve-t+C=1+v        A1

\n

ke-t-1=v

\n

Attempt to find k with initial conditions t=0, v=v0        M1

\n

k=1+v0

\n

e-t1+v0=1+v        A1

\n

vt=1+v0e-t-1        AG

\n

 

\n

Note: condone use of modulus within the ln function(s)

\n

 

\n

[6 marks]

\n
a.
\n
\n

recognition that when t=T, v=0        M1

\n

1+v0e-T-1=0e-T=11+v0        A1

\n

eT=1+v0        AG

\n

 

\n

Note: Award M1A0 for substituting v0=eT-1 into v and showing that v=0.

\n

 

\n

[6 marks]

\n
b.i.
\n
\n

st=vtdt =1+v0e-t-1dt        (M1)

\n

=-1+v0e-t-t+D        A1

\n

(t=0, s=0 so) D=1+v0        A1

\n

st=-1+v0e-t-t+1+v0

\n

at smax, eT=1+v0T=ln1+v0

\n

Substituting into st=-1+v0e-t-t+1+v0        M1

\n

smax=-1+v011+v0-ln1+v0+v0+1        A1

\n

smax=v0-ln1+v0

\n

 

\n

[5 marks]

\n
b.ii.
\n
\n

METHOD 1

\n

vT-k=1+v0e-Tek-1        (M1)

\n

=1+v011+v0ek-1        A1

\n

=ek-1        AG

\n

 

\n

METHOD 2

\n

vT-k=1+v0e-T-k-1

\n

=eTe-T-k-1         M1

\n

=eT-T+k-1        A1

\n

=ek-1        AG

\n

 

\n

[2 marks]

\n
c.
\n
\n

METHOD 1

\n

vT+k=1+v0e-Te-k-1        (A1)

\n

=e-k-1       A1

\n

 

\n

METHOD 2

\n

vT+k=1+v0e-T+k-1        (A1)

\n

        =eTe-T+k-1

\n

=eT-T-k-1

\n

=e-k-1       A1

\n

 

\n

[2 marks]

\n
d.
\n
\n

METHOD 1

\n

vT-k+vT+k=ek+e-k-2       A1

\n

attempt to express as a square       M1

\n

=ek2-e-k22 0       A1

\n

so vT-k+vT+k0       AG

\n

 

\n

METHOD 2

\n

vT-k+vT+k=ek+e-k-2       A1

\n

Attempt to solve ddkek+e-k=0  k=0       M1

\n

minimum value of 2, (when k=0), hence ek+e-k2       R1

\n

so vT-k+vT+k0       AG

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.1.AHL.TZ2.11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

The number of messages, \nM\n, that six randomly selected teenagers sent during the month of October is shown in the following table. The table also shows the time, \nT\n, that they spent talking on their phone during the same month.

\n

\n

The relationship between the variables can be modelled by the regression equation \nM\n=\na\nT\n+\nb\n.

\n
\n

Write down the value of a and of b .

\n
[3]
\n
a.
\n
\n

Use your regression equation to predict the number of messages sent by a teenager that spent 154 minutes talking on their phone in October.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

evidence of set up             (M1)

\n

eg      correct value for a or b (accept r = 0.966856 )

\n

4.30161 , 163.330

\n

a = 4.30 , b = 163   (accept y = 4.30 x + 163 )        A1A1 N3

\n

[3 marks]

\n
a.
\n
\n

valid approach           (M1)

\n

eg      4.30 ( 154 ) + 163

\n

eg       825.778   ( 825.2  from 3 sf values)           (A1)

\n

number of messages = 826  (must be an integer)         A1  N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.2.SL.TZ0.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A rocket is travelling in a straight line, with an initial velocity of \n140\n m s−1. It accelerates to a new velocity of \n500\n m s−1 in two stages.

\n

During the first stage its acceleration, \na\n m s−2, after \nt\n seconds is given by \na\n\n(\nt\n)\n\n=\n240\n\n\nsin\n\n\n(\n\n2\nt\n\n)\n\n, where \n0\n\nt\n\nk\n.

\n
\n

The first stage continues for \nk\n seconds until the velocity of the rocket reaches \n375\n m s−1.

\n
\n

Find an expression for the velocity, v  m s−1, of the rocket during the first stage.

\n
[4]
\n
a.
\n
\n

Find the distance that the rocket travels during the first stage.

\n
[4]
\n
b.
\n
\n

During the second stage, the rocket accelerates at a constant rate. The distance which the rocket travels during the second stage is the same as the distance it travels during the first stage.

\n

Find the total time taken for the two stages.

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

recognizing that  v = a         (M1)

\n

correct integration         A1

\n

eg       120 cos ( 2 t ) + c

\n

attempt to find c using their v ( t )         (M1)

\n

eg       120 cos ( 0 ) + c = 140

\n

v ( t ) = 120 cos ( 2 t ) + 260          A1   N3

\n

[4 marks]

\n
a.
\n
\n

evidence of valid approach to find time taken in first stage           (M1)

\n

eg      graph,   120 cos ( 2 t ) + 260 = 375

\n

k = 1.42595          A1

\n

attempt to substitute their  v and/or their limits into distance formula           (M1)

\n

eg       0 1.42595 | v | ,    260 120 cos ( 2 t ) ,    0 k ( 260 120 cos ( 2 t ) ) d t

\n

353.608

\n

distance is 354 (m)         A1   N3

\n

[4 marks]

\n
b.
\n
\n

recognizing velocity of second stage is linear (seen anywhere)          R1

\n

eg      graph,    s = 1 2 h ( a + b ) ,    v = m t + c

\n

valid approach           (M1)

\n

eg       v = 353.608

\n

correct equation           (A1)

\n

eg       1 2 h ( 375 + 500 ) = 353.608

\n

time for stage two = 0.808248   ( 0.809142 from 3 sf)         A2

\n

2.23420   ( 2.23914 from 3 sf)

\n

2.23 seconds  ( 2.24 from 3 sf)         A1   N3

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.2.SL.TZ0.S_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-8-solving-trig-equations" ] }, { "Question": "
\n

The curve C has equation e2y=x3+y.

\n
\n

Show that dydx=3x22e2y-1.

\n
[3]
\n
a.
\n
\n

The tangent to C at the point Ρ is parallel to the y-axis.

\n

Find the x-coordinate of Ρ.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

attempts implicit differentiation on both sides of the equation        M1

\n

2e2ydydx=3x2+dydx        A1

\n

2e2y-1dydx=3x2        A1

\n

so dydx=3x22e2y-1        AG

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempts to solve 2e2y-1=0 for y        (M1)

\n

y=-0.346 =12ln12        A1

\n

attempts to solve e2y=x3+y for x given their value of y        (M1)

\n

x=0.946 =121-ln1213        A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "EXN.2.AHL.TZ0.6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Consider the lines \n\n\nL\n1\n\n\n and \n\n\nL\n2\n\n\n with respective equations

\n

\n\n\nL\n1\n\n\n\n\n:\n\n\ny\n=\n\n\n2\n3\n\nx\n+\n9\n  and  \n\n\nL\n2\n\n\n\n:\n\n\ny\n=\n\n2\n5\n\nx\n\n\n\n19\n\n5\n\n.

\n
\n

A third line, \n\n\nL\n3\n\n\n, has gradient \n\n\n3\n4\n\n.

\n
\n

Find the point of intersection of L 1 and L 2 .

\n
[2]
\n
a.
\n
\n

Write down a direction vector for L 3 .

\n
[1]
\n
b.
\n
\n

L 3 passes through the intersection of L 1 and L 2 .

\n

Write down a vector equation for L 3 .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

valid approach           (M1)

\n

eg      L 1 = L 2 x = 12 y = 1

\n

( 12 1 )   (exact)         A1  N2

\n

[2 marks]

\n
a.
\n
\n

( 4 3 )   (or any multiple of ( 4 3 ) )       A1  N1

\n

[1 mark]

\n
b.
\n
\n

any correct equation in the form r = a + t b (accept any parameter for t ) where 
a is a position vector for a point on L 1 , and b is a scalar multiple of  ( 4 3 )        A2  N2

\n

eg       r  = ( 12 1 ) + t ( 4 3 )

\n

Note: Award A1 for the form a + t b, A1 for the form L = a + t b, A0 for the form r = b + t a.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.2.SL.TZ0.S_2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-10-solving-equations-graphically-and-analytically" ] }, { "Question": "
\n

In this question you will be exploring the strategies required to solve a system of linear differential equations.

\n

 

\n

Consider the system of linear differential equations of the form:

\n

dxdt=x-y  and  dydt=ax+y,

\n

where x, y, t+ and a is a parameter.

\n

First consider the case where a=0.

\n
\n

Now consider the case where a=-1.

\n
\n

Now consider the case where a=-4.

\n
\n

From previous cases, we might conjecture that a solution to this differential equation is y=Feλt, λ and F is a constant.

\n
\n

By solving the differential equation dydt=y, show that y=Aet where A is a constant.

\n
[3]
\n
a.i.
\n
\n

Show that dxdt-x=-Aet.

\n
[1]
\n
a.ii.
\n
\n

Solve the differential equation in part (a)(ii) to find x as a function of t.

\n
[4]
\n
a.iii.
\n
\n

By differentiating dydt=-x+y with respect to t, show that d2ydt2=2dydt.

\n
[3]
\n
b.i.
\n
\n

By substituting Y=dydt, show that Y=Be2t where B is a constant.

\n
[3]
\n
b.ii.
\n
\n

Hence find y as a function of t.

\n
[2]
\n
b.iii.
\n
\n

Hence show that x=-B2e2t+C, where C is a constant.

\n
[3]
\n
b.iv.
\n
\n

Show that d2ydt2-2dydt-3y=0.

\n
[3]
\n
c.i.
\n
\n

Find the two values for λ that satisfy d2ydt2-2dydt-3y=0.

\n
[4]
\n
c.ii.
\n
\n

Let the two values found in part (c)(ii) be λ1 and λ2.

\n

Verify that y=Feλ1t+Geλ2t is a solution to the differential equation in (c)(i),where G is a constant.

\n
[4]
\n
c.iii.
\n
", "Markscheme": "
\n

METHOD 1

\n

dydt=y

\n

dyy=dt               (M1)

\n

lny=t+c  OR  lny=t+c             A1A1

\n


Note: Award A1 for lny and A1 for t and c.

\n


y=Aet             AG

\n

 

\n

METHOD 2

\n

rearranging to dydt-y=0 AND multiplying by integrating factor e-t               M1

\n

ye-t=A             A1A1

\n

y=Aet             AG

\n

 

\n

[3 marks]

\n
a.i.
\n
\n

substituting y=Aet into differential equation in x               M1

\n

dxdt=x-Aet

\n

dxdt-x=-Aet             AG

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

integrating factor (IF) is e-1dt               (M1)

\n

=e-t               (A1)

\n

e-tdxdt-xe-t=-A

\n

xe-t=-At+D               (A1)

\n

x=-At+Det               A1

\n


Note: The first constant must be A, and the second can be any constant for the final A1 to be awarded. Accept a change of constant applied at the end.

\n

 

\n

[4 marks]

\n
a.iii.
\n
\n

d2ydt2=-dxdt+dydt               A1

\n


EITHER

\n

=-x+y+dydt               (M1)

\n

=dydt+dydt               A1

\n


OR

\n

=-x+y+-x+y               (M1)

\n

=2-x+y               A1

\n


THEN

\n

=2dydt               AG

\n


[3 marks]

\n
b.i.
\n
\n

dYdt=2Y               A1

\n

dYY=2dt               M1

\n

lnY=2t+c  OR  lnY=2t+c               A1

\n

Y=Be2t               AG

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

dydt=Be2t

\n

y=Be2tdt              M1

\n

y=B2e2t+C              A1

\n


Note:
The first constant must be B, and the second can be any constant for the final A1 to be awarded. Accept a change of constant applied at the end.

\n

 

\n

[2 marks]

\n
b.iii.
\n
\n

METHOD 1

\n

substituting dydt=Be2t and their (iii) into dydt=-x+y              M1(M1)

\n

Be2t=-x+B2e2t+C              A1

\n

x=-B2e2t+C              AG

\n

Note: Follow through from incorrect part (iii) cannot be awarded if it does not lead to the AG.

\n


METHOD 2

\n

dxdt=x-B2e2t-C

\n

dxdt-x=-B2e2t-C

\n

dxe-tdt=-B2et-Ce-t              M1

\n

xe-t=-B2et-Ce-tdt

\n

xe-t=-B2et-Ce-t+D              A1

\n

x=-B2e2t+C+Det

\n

dydt=-x+yBe2t=B2e2t-C-Det+B2e2t+CD=0              M1

\n

x=-B2e2t+C              AG

\n

 

\n

[3 marks]

\n
b.iv.
\n
\n

dydt=-4x+y

\n

d2ydt2=-4dxdt+dydt seen anywhere              M1

\n

 

\n

METHOD 1

\n

d2ydt2=-4x-y+dydt

\n

attempt to eliminate x              M1

\n

=-414y-dydt-y+dydt

\n

=2dydt+3y              A1

\n

d2ydt2-2dydt-3y=0              AG

\n

 

\n

METHOD 2

\n

rewriting LHS in terms of x and y              M1

\n

d2ydt2-2dydt-3y=-8x+5y-2-4x+y-3y              A1

\n

=0              AG

\n

 

\n

[3 marks]

\n
c.i.
\n
\n

dydt=Fλeλt, d2ydt2=Fλ2eλt               (A1)

\n

Fλ2eλt-2Fλeλt-3Feλt=0               (M1)

\n

λ2-2λ-3=0  (since eλt0)              A1

\n

λ1 and λ2 are 3 and -1 (either order)              A1

\n

 

\n

[4 marks]

\n
c.ii.
\n
\n

METHOD 1

\n

y=Fe3t+Ge-t

\n

dydt=3Fe3t-Ge-t, d2ydt2=9Fe3t-Ge-t                      (A1)(A1)

\n

d2ydt2-2dydt-3y=9Fe3t+Ge-t-23Fe3t-Ge-t-3Fe3t-Ge-t              M1

\n

=9Fe3t+Ge-t-6Fe3t+2Ge-t-3Fe3t-3Ge-t              A1

\n

=0              AG

\n

 

\n

METHOD 2

\n

y=Feλ1t+Geλ2t

\n

dydt=Fλ1eλ1t+Gλ2eλ2t, d2ydt2=Fλ12eλ1t+Gλ22eλ2t                      (A1)(A1)

\n

d2ydt2-2dydt-3y=Fλ12eλ1t+Gλ22eλ2t-2Fλ1eλ1t+Gλ2eλ2t-3Feλ1t+Geλ2t              M1

\n

=Feλ1tλ2-2λ-3+Geλ2tλ2-2λ-3              A1

\n

=0              AG

\n

 

\n

[4 marks]

\n
c.iii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
b.iv.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
", "question_id": "21N.3.AHL.TZ0.2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

The following diagram shows the graph of y=arctan2x+1+π4 for x, with asymptotes at y=-π4 and y=3π4.

\n

\n
\n

Describe a sequence of transformations that transforms the graph of y=arctan x to the graph of y=arctan2x+1+π4 for x.

\n
[3]
\n
a.
\n
\n

Show that arctanp+arctanqarctanp+q1-pq where p, q>0 and pq<1.

\n
[4]
\n
b.
\n
\n

Verify that arctan 2x+1=arctan xx+1+π4 for x, x>0.

\n
[3]
\n
c.
\n
\n

Using mathematical induction and the result from part (b), prove that Σr=1narctan12r2=arctannn+1 for n+.

\n
[9]
\n
d.
\n
", "Markscheme": "
\n

EITHER
horizontal stretch/scaling with scale factor 12

\n


Note: Do not allow ‘shrink’ or ‘compression’

\n


followed by a horizontal translation/shift 12 units to the left           A2

\n


Note: Do not allow ‘move’

\n


OR

\n

horizontal translation/shift 1 unit to the left

\n

followed by horizontal stretch/scaling with scale factor 12     A2

\n


THEN

\n

vertical translation/shift up by π4 (or translation through 0π4          A1
(may be seen anywhere)

\n

 

\n

[3 marks]

\n
a.
\n
\n

let α=arctanp and β=arctanq        M1

\n

p=tanα and q=tanβ        (A1)

\n

tanα+β=p+q1-pq        A1

\n

α+β=arctanp+q1-pq        A1

\n

so arctanp+arctanqarctanp+q1-pq where p, q>0 and pq<1.       AG

\n

 

\n

[4 marks]

\n
b.
\n
\n

METHOD 1

\n

π4=arctan1 (or equivalent)        A1

\n

arctanxx+1+arctan1=arctanxx+1+11-xx+11        A1

\n

=arctanx+x+1x+1x+1-xx+1        A1

\n

=arctan2x+1       AG

\n

 

\n

METHOD 2

\n

tanπ4=1 (or equivalent)        A1

\n

Consider arctan2x+1-arctanxx+1=π4

\n

tanarctan2x+1-arctanxx+1

\n

=arctan2x+1-xx+11+x2x+1x+1        A1

\n

=arctan2x+1x+1-xx+1+x2x+1        A1

\n

=arctan 1       AG

\n

 

\n

METHOD 3

\n

tan arctan2x+1=tanarctanxx+1+π4

\n

tanπ4=1 (or equivalent)        A1

\n

LHS=2x+1        A1

\n

RHS=xx+1+11-xx+1=2x+1        A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

let Pn be the proposition that  Σr=1narctan12r2=arctannn+1 for n+

\n

consider P1

\n

when n=1, Σr=11arctan12r2=arctan12=RHS and so P1 is true          R1

\n

assume Pk is true, ie. Σr=1karctan12r2=arctankk+1 k+           M1

\n

 

\n

Note: Award M0 for statements such as “let n=k”.
Note: Subsequent marks after this M1 are independent of this mark and can be awarded.

\n

 

\n

consider Pk+1:

\n

Σr=1k+1arctan12r2=Σr=1karctan12r2+arctan12k+12           (M1)

\n

=arctankk+1+arctan12k+12        A1

\n

=arctankk+1+12k+121-kk+112k+12           M1

\n

=arctank+12k2+2k+12k+13-k        A1

\n

 

\n

Note: Award A1 for correct numerator, with (k+1) factored. Denominator does not need to be simplified

\n

 

\n

=arctank+12k2+2k+12k3+6k2+5k+2        A1

\n

 

\n

Note: Award A1 for denominator correctly expanded. Numerator does not need to be simplified. These two A marks may be awarded in any order

\n

 

\n

=arctank+12k2+2k+1k+22k2+2k+1=arctank+1k+2        A1

\n

 

\n

Note: The word ‘arctan’ must be present to be able to award the last three A marks

\n

 

\n

Pk+1 is true whenever Pk is true and P1 is true, so

\n

Pn is true for for n+         R1

\n

 

\n

Note: Award the final R1 mark provided at least four of the previous marks have been awarded.
Note: To award the final R1, the truth of Pk must be mentioned. ‘Pk implies Pk+1’ is insufficient to award the mark.

\n

 

\n

[9 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21M.1.AHL.TZ2.12", "topics": [ "topic-2-functions", "topic-3-geometry-and-trigonometry", "topic-1-number-and-algebra" ], "subtopics": [ "sl-2-11-transformation-of-functions", "ahl-3-9-reciprocal-trig-ratios-and-their-pythagorean-identities-inverse-circular-functions", "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

Consider the identity 2+7x1+2x1-xA1+2x+B1-x, where A,B.

\n
\n

Find the value of A and the value of B.

\n
[3]
\n
a.
\n
\n

Hence, expand 2+7x1+2x1-x in ascending powers of x, up to and including the term in x2.

\n
[4]
\n
b.
\n
\n

Give a reason why the series expansion found in part (b) is not valid for x=34.

\n
[1]
\n
c.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

 

\n

2+7xA1-x+B1+2x

\n

 

\n

EITHER

\n

substitutes x=1 and attempts to solve for B and substitutes x=-12 and attempts to solve for A        (M1)

\n

9=3BB=3 ; 3A2=-32A=-1

\n

 

\n

OR

\n

forms A+B=2 and -A+2B=7 and attempts to solve for A and B        (M1)

\n

 

\n

THEN

\n

A=-1 and B=3        A1A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

uses the binomial expansion on either 31-x-1 or 1+2x-1       M1

\n

31-x-1=31+x+x2+        A1

\n

1+2x-1=1-2x+-1-22!2x2+=1-2x+4x2+        A1

\n

3+3x+3x2-1-2x+4x2

\n

so the expansion is 2+5x-x2 (in ascending powers of x)        A1

\n

 

\n

[4 marks]

\n
b.
\n
\n

1+2x-1 (is convergent) requires x<12 and x=34 is outside this so the expansion is not valid        R1

\n

 

\n

[1 mark]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXN.2.AHL.TZ0.7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\nx\n\n8\n,  \ng\n\n(\nx\n)\n\n=\n\n\nx\n4\n\n\n\n3\n  and  \nh\n\n(\nx\n)\n\n=\nf\n\n(\n\ng\n\n(\nx\n)\n\n\n)\n\n.

\n
\n

Find h ( x ) .

\n
[2]
\n
a.
\n
\n

Let C be a point on the graph of h . The tangent to the graph of h at C is parallel to the graph of f .

\n

Find the x -coordinate of C .

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

attempt to form composite (in any order)        (M1)

\n

eg        f ( x 4 3 ) ,   ( x 8 ) 4 3

\n

h ( x ) = x 4 11        A1  N2

\n

[2 marks]

\n
a.
\n
\n

recognizing that the gradient of the tangent is the derivative        (M1)

\n

eg        h

\n

correct derivative (seen anywhere)        (A1)

\n

h ( x ) = 4 x 3

\n

correct value for gradient of f (seen anywhere)        (A1)

\n

f ( x ) = 1 ,   m = 1

\n

setting their derivative equal to 1         (M1)

\n

4 x 3 = 1

\n

0.629960

\n

x = 1 4 3 (exact),  0.630        A1  N3

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.2.SL.TZ0.S_3", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Prove by contradiction that log25 is an irrational number.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

assume there exist p,q where q1 such that log25=pq         M1A1

\n

 

\n

Note: Award M1 for attempting to write the negation of the statement as an assumption. Award A1 for a correctly stated assumption.

\n

 

\n

log25=pq5=2pq        A1

\n

5q=2p         A1

\n

 

\n

EITHER

\n

5 is a factor of 5q but not a factor of 2p        R1

\n

 

\n

OR

\n

2 is a factor of 2p but not a factor of 5q        R1

\n

 

\n

OR

\n

5q is odd and 2p is even        R1

\n

 

\n

THEN

\n

no p,q (where q1) satisfy the equation 5q=2p and this is a contradiction        R1

\n

so log25 is an irrational number        AG

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.2.AHL.TZ0.8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

At a café, the waiting time between ordering and receiving a cup of coffee is dependent upon the number of customers who have already ordered their coffee and are waiting to receive it.

\n

Sarah, a regular customer, visited the café on five consecutive days. The following table shows the number of customers, x, ahead of Sarah who have already ordered and are waiting to receive their coffee and Sarah’s waiting time, y minutes.

\n

\n

The relationship between x and y can be modelled by the regression line of y on x with equation y=ax+b.

\n
\n

Find the value of a and the value of b.

\n
[2]
\n
a.i.
\n
\n

Write down the value of Pearson’s product-moment correlation coefficient, r.

\n
[1]
\n
a.ii.
\n
\n

Interpret, in context, the value of a found in part (a)(i).

\n
[1]
\n
b.
\n
\n

On another day, Sarah visits the café to order a coffee. Seven customers have already ordered their coffee and are waiting to receive it.

\n

Use the result from part (a)(i) to estimate Sarah’s waiting time to receive her coffee.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

a=0.805084 and b=2.88135

\n

a=0.805 and b=2.88            A1A1

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

r=0.97777

\n

r=0.978     A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

a represents the (average) increase in waiting time (0.805 mins) per additional customer (waiting to receive their coffee)         R1

\n

 

\n

[1 mark]

\n
b.
\n
\n

attempt to substitute x=7 into their equation       (M1)

\n

8.51693

\n

8.52 (mins)        A1

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.2.SL.TZ2.1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A biased coin is weighted such that the probability, p, of obtaining a tail is 0.6. The coin is tossed repeatedly and independently until a tail is obtained.

\n

Let E be the event “obtaining the first tail on an even numbered toss”.

\n

Find PE.

\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

METHOD 1

\n

En is the event “the first tail occurs on the 2nd, 4th, 6th, …, 2nth toss”

\n

PE=Σn=1PEn         (A1)

\n

 

\n

Note: Award A1 for deducing that either 1 head before a tail or 3 heads before a tail or 5 heads before a tail etc. is required. In other words, deduces 2n-1 heads before a tail.

\n

 

\n

PE=0.4×0.6+0.43×0.6+0.45×0.6+         M1A1

\n

 

\n

Note: Award M1 for attempting to form an infinite geometric series.

\n

Note: Award A1 for PE=Σn=10.42n-10.6.

\n

 

\n

uses S=u11-r with u1=0.6×0.4 and r=0.42         (M1)

\n

 

\n

Note: Award M1 for using S=u11-r with u1=0.4 and r=0.42

\n

 

\n

=0.6×0.41-0.42        A1

\n

=0.286 =27        A1

\n

 

\n

METHOD 2

\n

let T1 be the event “tail occurs on the first toss”

\n

uses PE=PET1PT1+PET1'PT1'         M1

\n

concludes that PET1=0 and so PE=PET1'PT1'         R1

\n

PET1'=PE'=1-PE         A1

\n

 

\n

Note: Award A1 for concluding: given that a tail is not obtained on the first toss, then PET1' is the probability that the first tail is obtained after a further odd number of tosses, PE'.

\n

 

\n

PT1'=0.4

\n

PE=0.41-PE         A1

\n

attempts to solve for PE         (M1)

\n

=0.286 =27         A1

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXN.2.AHL.TZ0.9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The following diagram shows a right-angled triangle, \n\nABC\n\n, with \n\nAC\n\n=\n10\n\n\ncm\n\n\n\nAB\n\n=\n6\n\n\ncm\n\n and \n\nBC\n\n=\n8\n\n\ncm\n\n.

\n

The points \n\nD\n\n and \n\nF\n\n lie on \n\n[\n\n\nAC\n\n\n]\n\n.
\n\n[\n\n\nBD\n\n\n]\n\n is perpendicular to \n\n[\n\n\nAC\n\n\n]\n\n.
\n\nBEF\n\n is the arc of a circle, centred at \n\nA\n\n.
The region \nR\n is bounded by \n\n[\n\n\nBD\n\n\n]\n\n, \n\n[\n\n\nDF\n\n\n]\n\n and arc \n\nBEF\n\n.

\n

\n
\n

Find B A ^ C .

\n
[2]
\n
a.
\n
\n

Find the area of R .

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

correct working        (A1)

\n

eg        sin α = 8 10 ,   cos θ = 6 10 ,   cos B A ^ C = 6 2 + 10 2 8 2 2 × 6 × 10

\n

0.927295

\n

B A ^ C = 0.927   ( = 53.1 )       (A1)  N2

\n

[2 marks]

\n
a.
\n
\n

Note: There may be slight differences in the final answer, depending on the approach the candidate uses in part (b). Accept a final answer that is consistent with their working.

\n

correct area of sector  ABF (seen anywhere)        (A1)

\n

eg        1 2 × 6 2 × 0.927 ,   53.1301 360 × π × 6 2 ,   16 .6913

\n

correct expression (or value) for either [ AD ] or [ BD ] (seen anywhere)        (A1)

\n

eg        AD = 6 cos ( B A ^ C ) ( = 3.6 )

\n

            BD = 6 sin ( 53.1 ) ( = 4.8 )

\n

correct area of triangle ABD (seen anywhere)        (A1)

\n

eg        1 2 × 6 cos B A ^ D × 6 sin B A ^ D ,   9 sin ( 2 B A ^ C ) 8.64 (exact)

\n

appropriate approach (seen anywhere)        (M1)

\n

eg        A triangle ABD A sector ,  their sector − their triangle ABD

\n

8.05131

\n

area of shaded region = 8.05 (cm2)       A1  N2

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.2.SL.TZ0.S_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

The points A5,-2,5, B5,4,-1, C-1,-2,-1 and D7,-4,-3 are the vertices of a right-pyramid.

\n
\n

The line L passes through the point D and is perpendicular to Π.

\n
\n

Find the vectors AB and AC.

\n
[2]
\n
a.
\n
\n

Use a vector method to show that BA^C=60°.

\n
[3]
\n
b.
\n
\n

Show that the Cartesian equation of the plane Π that contains the triangle ABC is -x+y+z=-2.

\n
[3]
\n
c.
\n
\n

Find a vector equation of the line L.

\n
[1]
\n
d.i.
\n
\n

Hence determine the minimum distance, dmin, from D to Π.

\n
[4]
\n
d.ii.
\n
\n

Find the volume of right-pyramid ABCD.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

 

\n

AB=06-6 =601-1        A1

\n

AC=-60-6 =6-10-1        A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

attempts to use  cosBA^C=AB·ACABAC        (M1)

\n

=06-6·-60-672×72        A1

\n

=12        A1

\n

so BA^C=60°        AG

\n

 

\n

[3 marks]

\n
b.
\n
\n

attempts to find a vector normal to Π        M1

\n

for example, AB×AC=-363636 =36-111 leading to        A1

\n

a vector normal to Π is n=-111

\n

 

\n

EITHER

\n

substitutes 5,-2,-5 (or 5,4,-1 or -1,-2,-1) into -x+y+z=d and attempts to find the value of d

\n

for example, d=-5-2+5 =-2        M1

\n

 

\n

OR

\n

attempts to use r·n=a·n        M1

\n

for example, xyz·-111=5-25·-111

\n

 

\n

THEN

\n

leading to the Cartesian equation of Π as -x+y+z=-2        AG

\n

 

\n

[3 marks]

\n
c.
\n
\n

r=7-4-3+λ-111 λ        A1

\n

 

\n

[1 mark]

\n
d.i.
\n
\n

substitutes x=7-λ, y=-4+λ, z=-3+λ into -x+y+z=-2        (M1)

\n

-7-λ+-4+λ+-3+λ=-2 3λ=12

\n

λ=4        A1

\n

shows a correct calculation for finding dmin, for example, attempts to find

\n

4-111        M1

\n

dmin=43 =6.93        A1

\n

 

\n

[4 marks]

\n
d.ii.
\n
\n

let the area of triangle ABC be A

\n

 

\n

EITHER

\n

attempts to find A=12AB×AC, for example       M1

\n

A=12-363636

\n

 

\n

OR

\n

attempts to find 12ABACsinθ, for example       M1

\n

A=12×62×62×32  (where sinπ3=32)

\n

 

\n

THEN

\n

A=183 =31.2       A1

\n

uses V=13Ah where A is the area of triangle ABC and h=dmin       M1

\n

 V=13×183×43

\n

=72       A1

\n

 

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "EXN.2.AHL.TZ0.11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

The first two terms of a geometric sequence are \n\n\nu\n1\n\n\n=\n2.1\n and \n\n\nu\n2\n\n\n=\n2.226\n.

\n
\n

Find the value of r .

\n
[2]
\n
a.
\n
\n

Find the value of u 10 .

\n
[2]
\n
b.
\n
\n

Find the least value of n such that  S n > 5543 .

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

valid approach        (M1)

\n

eg        u 1 u 2 ,   2.226 2.1 ,   2.226 = 2.1 r

\n

r = 1.06   (exact)       A1  N2

\n

[2 marks]

\n
a.
\n
\n

correct substitution        (A1)

\n

eg        2.1 × 1.06 9

\n

3.54790        A1  N2

\n

u 10 = 3.55

\n

[2 marks]

\n
b.
\n
\n

correct substitution into  S n formula        (A1)

\n

eg      2.1 ( 1.06 n 1 ) 1.06 1 ,   2.1 ( 1.06 n 1 ) 1.06 1 > 5543 ,   2.1 ( 1.06 n 1 ) = 332.58 ,  sketch of  S n and  y = 5543

\n

correct inequality for n or crossover values       A1

\n

eg        n > 87.0316 ,   S 87 = 5532.73   and   S 88 = 5866.79

\n

n = 88        A1  N2

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19N.2.SL.TZ0.S_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

Let fx=3x-40.15x2 for 0x3.

\n
\n

Sketch the graph of f on the grid below.

\n

\n
[3]
\n
a.
\n
\n

Find the value of x for which f(x)=0.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

         A1A1A1

\n

 

\n

Note: Award A1 for a smooth concave down curve with generally correct shape. If first mark is awarded, award A1 for local maximum and x-intercept in approximately correct position, award A1 for endpoints at x=0 and x=3 with approximately correct y-coordinates.

\n

 

\n

[3 marks]

\n
a.
\n
\n

recognizing that f(x)=0 at local maximum                 (M1)

\n

x=2.33084

\n

x=2.33                           A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.SL.TZ2.2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

An arithmetic sequence has first term 60 and common difference -2.5.

\n
\n

Given that the kth term of the sequence is zero, find the value of k.

\n
[2]
\n
a.
\n
\n

Let Sn denote the sum of the first n terms of the sequence.

\n

Find the maximum value of Sn.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

attempt to use u1+n-1d=0            (M1)

\n

60-2.5k-1=0

\n

k=25                          A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

attempting to express Sn in terms of n            (M1)

\n

use of a graph or a table to attempt to find the maximum sum            (M1)

\n

=750                A1

\n

 

\n

METHOD 2

\n


EITHER

\n

recognizing maximum occurs at n=25           (M1)

\n

S25=25260+0, S25=2522×60+24×-2.5          (A1)

\n


OR

\n

attempting to calculate S24          (M1)

\n

S24=2422×60+23×-2.5          (A1)

\n


THEN

\n

=750                A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.SL.TZ2.3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The diagram below shows a triangular-based pyramid with base  ADC .
Edge  BD is perpendicular to the edges  AD and  CD .

\n

\n

AC = 28.4 cm ,   AB = x cm ,   BC = x + 2 cm ,   A B ^ C = 0.667 ,   B A ^ D = 0.611

\n

Calculate  AD

\n
", "Markscheme": "
\n

evidence of choosing cosine rule        (M1)

\n

eg        a 2 = b 2 + c 2 2 b c cos A

\n

correct substitution to find  AB         (A1)

\n

eg        28.4 2 = x 2 + ( x + 2 ) 2 2 x ( x + 2 ) cos ( 0.667 )

\n

x = 42.2822        A2

\n

appropriate approach to find  AD         (M1)

\n

eg        AD = x cos ( 0.611 ) ,   cos ( 0.611 ) = AD 42.2822

\n

34.6322

\n

AD = 34.6        A1  N3

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.2.SL.TZ0.S_6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The following table shows the probability distribution of a discrete random variable \nX\n, where \na\n\n0\n and \nb\n\n0\n.

\n

\n
\n

Show that  b = 0.3 a .

\n
[1]
\n
a.
\n
\n

Find the difference between the greatest possible expected value and the least possible expected value.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

correct approach  A1

\n

eg        0.2 + 0.5 + b + a = 1 ,   0.7 + a + b = 1

\n

b = 0.3 a        AG  N0

\n

[1 mark]

\n
a.
\n
\n

correct substitution into  E ( X )         (A1)

\n

eg        0.2 + 4 × 0.5 + a × b + ( a + b 0.5 ) × a ,   0.2 + 2 + a × b 0.2 a

\n

valid attempt to express E ( X ) in one variable       M1

\n

eg        0.2 + 4 × 0.5 + a × ( 0.3 a ) + ( 0.2 ) × a ,   2.2 + 0.1 a a 2 ,

\n

           0.2 + 4 × 0.5 + ( 0.3 b ) × b + ( 0.2 ) × ( 0.3 b ) ,    2.14 + 0.5 b b 2

\n

correct value of greatest  E ( X )         (A1)

\n

2.2025   (exact)

\n

valid attempt to find least value        (M1)

\n

eg       graph with minimum indicated,  E ( 0 )   and   E ( 0.3 )

\n

           ( 0 2.2 )   and  ( 0.3 2.14 ) if  E ( X )  in terms of a

\n

           ( 0 2.14 )   and  ( 0.3 2.2 ) if  E ( X )  in terms of b

\n

correct value of least  E ( X )         (A1)

\n

eg        2.14   (exact)

\n

difference = 0.0625 (exact)       A1  N2

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.2.SL.TZ0.S_7", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

At a school, 70% of the students play a sport and 20% of the students are involved in theatre. 18% of the students do neither activity.

\n

A student is selected at random.

\n
\n

At the school 48% of the students are girls, and 25% of the girls are involved in theatre.

\n

A student is selected at random. Let G be the event “the student is a girl” and let T be the event “the student is involved in theatre”.

\n
\n

Find the probability that the student plays a sport and is involved in theatre.

\n
[2]
\n
a.
\n
\n

Find the probability that the student is involved in theatre, but does not play a sport.

\n
[2]
\n
b.
\n
\n

Find PGT.

\n
[2]
\n
c.
\n
\n

Determine if the events G and T are independent. Justify your answer.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

EITHER

\n

PS+PT+PS'T'-PST=1  OR  PST=PS'T''          (M1)

\n

0.7+0.2+0.18-PST=1  OR  PST=1-0.18

\n


OR

\n

a clearly labelled Venn diagram        (M1)

\n


THEN

\n

PST=0.08  (accept 8%)              A1

\n

 

\n

Note: To obtain the M1 for the Venn diagram all labels must be correct and in the correct sections. For example, do not accept 0.7 in the area corresponding to ST'.

\n

 

\n

[2 marks]

\n
a.
\n
\n

EITHER

\n

PTS'=PT-PTS=0.2-0.08  OR

\n

PTS'=PTS-PS=0.82-0.7         (M1)

\n

 
OR

\n

a clearly labelled Venn diagram including PSPT and PST         (M1)

\n


THEN

\n

=0.12  (accept 12%)              A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

PGT=PT/GPG  0.25×0.48         (M1)

\n

=0.12             A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

METHOD 1

\n

PG×PT=0.48×0.2=0.096             A1

\n

PG×PTPGT  G and T are not independent             R1

\n

 

\n

METHOD 2

\n

PTG=0.25             A1

\n

PTGPT  G and T are not independent             R1

\n

 

\n

Note: Do not award A0R1.

\n

 

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21M.2.SL.TZ2.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

This question asks you to explore some properties of polygonal numbers and to determine and prove interesting results involving these numbers.

\n


A polygonal number is an integer which can be represented as a series of dots arranged in the shape of a regular polygon. Triangular numbers, square numbers and pentagonal numbers are examples of polygonal numbers.

\n

For example, a triangular number is a number that can be arranged in the shape of an equilateral triangle. The first five triangular numbers are 1, 3, 6, 10 and 15.

\n

The following table illustrates the first five triangular, square and pentagonal numbers respectively. In each case the first polygonal number is one represented by a single dot.

\n

\n

For an r-sided regular polygon, where r+, r3, the nth polygonal number Prn is given by

\n

Prn=r-2n2-r-4n2, where n+.

\n

Hence, for square numbers, P4n=4-2n2-4-4n2=n2.

\n
\n

The nth pentagonal number can be represented by the arithmetic series

\n

P5n=1+4+7++3n-2.

\n
\n

For triangular numbers, verify that P3n=nn+12.

\n
[2]
\n
a.i.
\n
\n

The number 351 is a triangular number. Determine which one it is.

\n
[2]
\n
a.ii.
\n
\n

Show that P3n+P3n+1n+12.

\n
[2]
\n
b.i.
\n
\n

State, in words, what the identity given in part (b)(i) shows for two consecutive triangular numbers.

\n
[1]
\n
b.ii.
\n
\n

For n=4, sketch a diagram clearly showing your answer to part (b)(ii).

\n
[1]
\n
b.iii.
\n
\n

Show that 8P3n+1 is the square of an odd number for all n+.

\n
[3]
\n
c.
\n
\n

Hence show that P5n=n3n-12 for n+.

\n
[3]
\n
d.
\n
\n

By using a suitable table of values or otherwise, determine the smallest positive integer, greater than 1, that is both a triangular number and a pentagonal number.

\n
[5]
\n
e.
\n
\n

A polygonal number, Prn, can be represented by the series

\n

Σm=1n1+m-1r-2 where r+, r3.

\n

Use mathematical induction to prove that Prn=r-2n2-r-4n2 where n+.

\n
[8]
\n
f.
\n
", "Markscheme": "
\n

P3n=3-2n2-3-4n2  OR  P3n=n2--n2        A1

\n

P3n=n2+n2        A1

\n

 

\n

Note: Award A0A1 if P3n=n2+n2 only is seen.

\n

Do not award any marks for numerical verification.

\n

 

\n

so for triangular numbers, P3n=nn+12        AG

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

METHOD 1

\n

uses a table of values to find a positive integer that satisfies P3n=351        (M1)

\n

for example, a list showing at least 3 consecutive terms 325, 351, 378

\n

 

\n

Note: Award (M1) for use of a GDC’s numerical solve or graph feature.

\n

 

\n

n=26  (26th triangular number)        A1

\n

 

\n

Note: Award A0 for n=27,26. Award A0 if additional solutions besides n=26 are given.

\n

 

\n

METHOD 2

\n

attempts to solve nn+12=351 n2+n-702=0 for n        (M1)

\n

n=-1±12-41-7022  OR  n-26n+27=0

\n

n=26  (26th triangular number)        A1

\n

 

\n

Note: Award A0 for n=27,26. Award A0 if additional solutions besides n=26 are given.

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

attempts to form an expression for P3n+P3n+1 in terms of n        M1

\n

 

\n

EITHER

\n

P3n+P3n+1nn+12+n+1n+22

\n

n+12n+22 2n+1n+12         A1

\n

 

\n

OR

\n

P3n+P3n+1n22+n2+n+122+n+12

\n

n2+n2+n2+2n+1+n+12  n2+2n+1         A1

\n

 

\n

THEN

\n

n+12         AG

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

the sum of the nth and n+1th triangular numbers

\n

is the n+1th square number         A1

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

      A1

\n

 

\n

Note: Accept equivalent single diagrams, such as the one above, where the 4th and 5th triangular numbers and the 5th square number are clearly shown.
Award A1 for a diagram that show P34 (a triangle with 10 dots) and P35 (a triangle with 15 dots) and P45 (a square with 25 dots).

\n

 

\n

[1 mark]

\n
b.iii.
\n
\n

METHOD 1

\n

8P3n+1=8nn+12+1 =4nn+1+1          A1

\n

attempts to expand their expression for 8P3n+1          (M1)

\n

=4n2+4n+1

\n

=2n+12          A1

\n

and 2n+1 is odd          AG

\n

 

\n

METHOD 2

\n

8P3n+1=8n+12-P3n+1+1=8n+12-n+1n+22+1  A1

\n

attempts to expand their expression for 8P3n+1          (M1)

\n

8n2+2n+1-4n2+3n+2+1 =4n2+4n+1

\n

=2n+12          A1

\n

and 2n+1 is odd          AG

\n

 

\n

Method 3

\n

8P3n+1=8nn+12+1 =An+B2 (where A,B+)          A1

\n

attempts to expand their expression for 8P3n+1          (M1)

\n

4n2+4n+1 =A2n2+2ABn+B2

\n

now equates coefficients and obtains B=1 and A=2

\n

=2n+12          A1

\n

and 2n+1 is odd          AG

\n

 

\n

[3 marks]

\n
c.
\n
\n

EITHER

\n

u1=1 and d=3          (A1)

\n

substitutes their u1 and their d into P5n=n22u1+n-1d          M1

\n

P5n=n22+3n-1 =n22+3n-3          A1

\n

 

\n

OR

\n

u1=1 and un=3n-2          (A1)

\n

substitutes their u1 and their un into P5n=n2u1+un          M1

\n

P5n=n21+3n-2          A1

\n

 

\n

OR

\n

P5n=31-2+32-2+33-2+3n-2

\n

P5n=31+32+33++3n-2n =31+2+3++n-2n        (A1)

\n

substitutes nn+12 into their expression for P5n          M1

\n

P5n=3nn+12-2n

\n

P5n=n23n+1-4          A1

\n

 

\n

OR

\n

attempts to find the arithmetic mean of n terms          (M1)

\n

=1+3n-22          A1

\n

multiplies the above expression by the number of terms n

\n

P5n=n21+3n-2          A1

\n

 

\n

THEN

\n

so P5n=n3n-12          AG

\n

 

\n

[3 marks]

\n
d.
\n
\n

METHOD 1

\n

forms a table of P3n values that includes some values for n>5         (M1)

\n

forms a table of P5m values that includes some values for m>5         (M1)

\n

 

\n

Note: Award (M1) if at least one P3n value is correct. Award (M1) if at least one P5m value is correct. Accept as above for n2+n values and 3m2-m values.

\n

 

\n

n=20 for triangular numbers          (A1)

\n

m=12 for pentagonal numbers          (A1)

\n

 

\n

Note: Award (A1) if n=20 is seen in or out of a table. Award (A1) if m=12 is seen in or out of a table. Condone the use of the same parameter for triangular numbers and pentagonal numbers, for example, n=20 for triangular numbers and n=12 for pentagonal numbers.

\n

 

\n

210 (is a triangular number and a pentagonal number)          A1

\n

 

\n

Note: Award all five marks for 210 seen anywhere with or without working shown.

\n

 

\n

METHOD 2

\n

EITHER

\n

attempts to express P3n=P5m as a quadratic in n         (M1)

\n

n2+n+m-3m2=0 (or equivalent)

\n

attempts to solve their quadratic in n         (M1)

\n

n=-1±12m2-4m+12=-1±12-4m-3m22

\n

 

\n

OR

\n

attempts to express P3n=P5m as a quadratic in m         (M1)

\n

3m2-m-n2+n=0 (or equivalent)

\n

attempts to solve their quadratic in m         (M1)

\n

m=1±12n2-12n+16=1±-12+12n2+n6

\n

 

\n

THEN

\n

n=20 for triangular numbers          (A1)

\n

m=12 for pentagonal numbers          (A1)

\n

210 (is a triangular number and a pentagonal number)          A1

\n

 

\n

METHOD 3

\n

nn+12=m3m-12

\n

let n=m+k n>m and so 3m2-m=m+km+k+1        M1

\n

2m2-2k+1m-k2+k=0          A1

\n

attempts to find the discriminant of their quadratic

\n

and recognises that this must be a perfect square        M1

\n

Δ=4k+12+8k2+k

\n

N2=4k+12+8k2+k =4k+13k+1

\n

determines that k=8 leading to 2m2-18m-72=0m=-3,12 and so m=12          A1

\n

210 (is a triangular number and a pentagonal number)          A1

\n

 

\n

 

\n

METHOD 4

\n

nn+12=m3m-12

\n

let m=n-k m<n and so n2+n=n-k3n-k-1       M1

\n

2n2-23k+1n+3k2+k=0          A1

\n

attempts to find the discriminant of their quadratic

\n

and recognises that this must be a perfect square        M1

\n

Δ=43k+12-83k2+k

\n

N2=43k+12-83k2+k =4k+13k+1

\n

determines that k=8 leading to 2n2-50n+200=0n=5,20 and so n=20          A1

\n

210 (is a triangular number and a pentagonal number)          A1

\n

 

\n

[5 marks]

\n
e.
\n
\n

Note: Award a maximum of R1M0M0A1M1A1A1R0 for a ‘correct’ proof using n and n+1.

\n

 

\n

consider n=1: Pr1=1+1-1r-2=1 and Pr1=r-212-r-412=1

\n

so true for n=1              R1 

\n

 

\n

Note: Accept Pr1=1 and Pr1=r-212-r-412=1.
Do not accept one-sided considerations such as 'Pr1=1 and so true for n=1'.
Subsequent marks after this R1 are independent of this mark can be awarded.

\n

 

\n

Assume true for n=k, ie. Prk=r-2k2-r-4k2          M1

\n

 

\n

Note: Award M0 for statements such as “let n=k ”. The assumption of truth must be clear.
Subsequent marks after this M1 are independent of this mark and can be awarded.

\n

 

\n

Consider n=k+1:

\n

(Prk+1 can be represented by the sum

\n

Σm=1k+11+m-1r-2=Σm=1k1+m-1r-2+1+kr-2 and so

\n

Prk+1=r-2k2-r-4k2+1+kr-2  Prk+1=Prk+1+kr-2         M1

\n

=r-2k2-r-4k+2+2kr-22         A1

\n

 =r-2k2+2k-r-4k+22

\n

=r-2k2+2k+1-r-2-r-4k+22         M1

\n

=r-2k+12-r-4k-r-42          (A1)

\n

 =r-2k+12-r-4k+12         A1

\n

hence true for n=1 and n=k true n=k+1 true         R1

\n

therefore true for all n+

\n

 

\n

Note: Only award the final R1 if the first five marks have been awarded. Award marks as appropriate for solutions that expand both the LHS and (given) RHS of the equation.

\n

 

\n

[8 marks]

\n
f.
\n
", "Examiners report": "
\n

Part (a) (i) was generally well done. Unfortunately, some candidates adopted numerical verification. Part (a) (ii) was generally well done with the majority of successful candidates using their GDC judiciously and disregarding = −27 as a possible solution. A few candidates interpreted the question as needing to deal with P3(351).

\n

Although part (b) (i) was generally well done, a significant number of candidates laboured unnecessarily to show the required result. Many candidates set their LHS to equal the RHS throughout the solution. Part (b) (ii) was generally not well done with many candidates unable to articulate clearly in words and symbols what the given identity shows for the sum of two consecutive triangular numbers. In part (b) (iii), most candidates were unable to produce a clear diagram illustrating the identity stated in part (b) (i). 

\n

Part (c) was reasonably well done. Most candidates were able to show algebraically that 8P3(n)+1=4n2+4n+1. A good number of candidates were then able to express 4n2+4n+1 as (2n+1)2 and conclude that (2n+1) is odd. Rather than making the connection that 4n2+4n+1 is a perfect square, many candidates attempted instead to analyse the parity of either 4n(n+1)+1 or 4n2+4n+1. As with part (b) (i), many candidates set their LHS to equal the RHS throughout the solution. A number of candidates unfortunately adopted numerical verification.

\n

Part (d) was not answered as well as anticipated with many candidates not understanding what was
required. Instead of using the given arithmetic series to show that P5(n)=n(3n-1)2, a large number of
candidates used P5(n)=(5-2)n2-(5-4)n2 . Unfortunately, a number of candidates adopted numerical verification.

\n

In part (e), the overwhelming majority of candidates who successfully determined that 210 is the smallest positive integer greater than 1 that is both triangular and pentagonal used a table of values. Unfortunately, a large proportion of these candidates seemingly spent quite a few minutes listing the first 20 triangular numbers and the first 12 pentagonal numbers. And it can be surmised that a number of these candidates constructed their table of values either without the use of a GDC or with the arithmetic functionality of a GDC rather than with a GDC's table of values facility. Candidates should be aware that a relevant excerpt from a table of values is sufficient evidence of correct working. A number of candidates started constructing a table of values but stopped before identifying 210. Disappointingly, a significant number of candidates attempted to solve P3(n)=P5(n) for n.

\n

Part (f) proved beyond the reach of most with only a small number of candidates successfully proving the given result. A significant number of candidates were unable to show that the result is true for n=1. A number of candidates established the validity of the base case for the RHS only while a number of other candidates attempted to prove the base case for r = 3. A large number of candidates did not state the inductive step correctly with the assumption of truth not clear. A number of candidates then either attempted to work backwards from the given result or misinterpreted the question and attempted to prove the result stated in the question stem rather than the result stated in the question. Some candidates who were awarded the first answer mark when considering the n=k+1 case were unable to complete the square or equivalent simplification correctly. Disappointingly, a significant number listed the steps involved in an induction proof without engaging in the actual proof.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "22M.3.AHL.TZ1.1", "topics": [ "topic-1-number-and-algebra", "topic-2-functions" ], "subtopics": [ "sl-1-6-simple-proof", "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots", "sl-1-2-arithmetic-sequences-and-series", "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

Consider the differential equation

\n

dydx=fyx, x>0

\n
\n

The curve y=fx for x>0 has a gradient function given by

\n

dydx=y2+3xy+2x2x2.

\n

The curve passes through the point 1,-1.

\n
\n

Use the substitution y=vx to show that dvfv-v=lnx+C where C is an arbitrary constant.

\n
[3]
\n
a.
\n
\n

By using the result from part (a) or otherwise, solve the differential equation and hence show that the curve has equation y=xtanlnx-1.

\n
[9]
\n
b.
\n
\n

The curve has a point of inflexion at x1,y1 where e-π2<x1<eπ2. Determine the coordinates of this point of inflexion.

\n
[6]
\n
c.
\n
\n

Use the differential equation dydx=y2+3xy+2x2x2 to show that the points of zero gradient on the curve lie on two straight lines of the form y=mx where the values of m are to be determined.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

y=vxdydx=v+xdvdx       M1

\n

v+xdvdx=fv       A1

\n

dvfv-v=dxx       A1

\n

integrating the RHS, dvfv-v=lnx+C       AG

\n

 

\n

[3 marks]

\n
a.
\n
\n

EITHER

\n

attempts to find fv       M1

\n

fv=v2+3v+2       (A1)

\n

substitutes their fv into dvfv-v       M1

\n

dvfv-v=dvv2+2v+2

\n

attempts to complete the square       (M1)

\n

dvv+12+1       A1

\n

arctanv+1 =lnx+C       A1

\n

 

\n

OR

\n

attempts to find fv       M1

\n

v+xdvdx=v2+3v+2       A1

\n

dvv2+2v+2=dxx       M1

\n

attempts to complete the square       (M1)

\n

dvv+12+1=dxx       A1

\n

arctanv+1 =lnx+C       A1

\n

 

\n

THEN

\n

when x=1v=-1 (or y=-1) and so C=0       M1

\n

substitutes for v into their expression       M1

\n

arctanyx+1=lnx

\n

yx+1=tanlnx       A1

\n

so y=xtanlnx-1       AG

\n

 

\n

[9 marks]

\n
b.
\n
\n

METHOD 1

\n

EITHER

\n

a correct graph of y=f'x (for approximately e-π2<x<eπ2) with a local minimum point below the x-axis        A2

\n

 

\n

Note: Award M1A1 for dydx=tanlnx+sec2lnx-1.

\n

 

\n

attempts to find the x-coordinate of the local minimum point on the graph of y=f'x        (M1)

\n

\n

OR

\n

a correct graph of y=f''x (for approximately e-π2<x<eπ2) showing the location of the x-intercept        A2

\n

 

\n

Note: Award M1A1 for d2ydx2=sec2lnxx+2sec2lnxtanlnxx.

\n

 

\n

attempts to find the x-intercept        (M1)

\n

\n

THEN

\n

x=0.629  =e-arctan12       A1

\n

attempts to find f0.629 fe-arctan12        (M1)

\n

the coordinates are 0.629,-0.943 e-arctan12,-32e-arctan12       A1

\n

 

\n

METHOD 2

\n

attempts implicit differentiation on dydx to find d2ydx2        M1

\n

d2ydx2=2y+3xxdydx-yx3 (or equivalent)

\n

d2ydx2=0y=-3x2 (dydxyx)       A1

\n

attempts to solve -3x2=xtanlnx-1 for x where e-π2<x<eπ2        M1

\n

x=0.629  =e-arctan12       A1

\n

attempts to find f0.629 f=e-arctan12        (M1)

\n

the coordinates are 0.629,-0.943 e-arctan12,-32e-arctan12       A1

\n

 

\n

[6 marks]

\n
c.
\n
\n

dydx=0y2+3xy+2x2=0        M1 

\n

attempts to solve y2+3xy+2x2=0 for y        M1 

\n

y+2xy+x=0 or y=-3x±3x2-42x22 =-3x±x2, x>0        A1

\n

y=-2x and y=-x m=-2,-1        A1

\n

 

\n

Note: Award M1 for stating dydx=0M1 for substituting y=mx into dydx=0, A1 for m+2m+1=0 and A1 for m=-2,-1y=-2x and y=-x.

\n

 

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "EXN.2.AHL.TZ0.12", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\nx\n4\n\n\n\n54\n\n\nx\n2\n\n\n+\n60\nx\n, for \n\n1\n\nx\n\n6\n. The following diagram shows the graph of \nf\n.

\n

\n

There are \nx\n-intercepts at \nx\n=\n0\n and at \nx\n=\np\n. There is a maximum at point \n\nA\n\n where \nx\n=\na\n, and a point of inflexion at point \n\nB\n\n where \nx\n=\nb\n.

\n
\n

Find the value of p .

\n
[2]
\n
a.
\n
\n

Write down the coordinates of A .

\n
[2]
\n
b.i.
\n
\n

Find the equation of the tangent to the graph of f at A .

\n
[2]
\n
b.ii.
\n
\n

Find the coordinates of B .

\n
[5]
\n
c.i.
\n
\n

Find the rate of change of f at B .

\n
[2]
\n
c.ii.
\n
\n

Let R be the region enclosed by the graph of f , the x -axis and the lines x = p and x = b . The region R is rotated 360º about the x -axis. Find the volume of the solid formed.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

evidence of valid approach        (M1)

\n

eg        f ( x ) = 0 ,   y = 0

\n

1.13843

\n

p = 1.14        A1  N2

\n

[2 marks]

\n
a.
\n
\n

0.562134 16.7641

\n

( 0.562 16.8 )        A2  N2

\n

[2 marks]

\n
b.i.
\n
\n

valid approach        (M1)

\n

eg      tangent at maximum point is horizontal,  f = 0

\n

y = 16.8  (must be an equation)       A1  N2

\n

[2 marks]

\n
b.ii.
\n
\n

METHOD 1 (using GDC)

\n

valid approach         M1

\n

eg       f = 0 ,  max/min on  f x = 3

\n

sketch of either  f or  f , with max/min or root (respectively)       (A1)

\n

x = 3        A1  N1

\n

substituting their x value into f         (M1)

\n

eg       f ( 3 )

\n

y = 225 (exact)  (accept   ( 3 225 ) )       A1  N1

\n

 

\n

METHOD 2 (analytical)

\n

f = 12 x 2 108        A1

\n

valid approach       (M1)

\n

eg       f = 0 ,   x = ± 3

\n

x = 3        A1  N1

\n

substituting their  x value into f         (M1)

\n

eg       f ( 3 )

\n

y = 225 (exact)  (accept   ( 3 225 ) )       A1  N1

\n

 

\n

[5 marks]

\n
c.i.
\n
\n

recognizing rate of change is  f         (M1)

\n

eg       y ,   f ( 3 )

\n

rate of change is 156 (exact)       A1  N2

\n

[2 marks]

\n
c.ii.
\n
\n

attempt to substitute either their limits or the function into volume formula        (M1)

\n

eg        1.14 3 f 2 ,   π ( x 4 54 x 2 + 60 x ) 2 d x ,   25 752.0

\n

80 902.3

\n

volume  = 80 900        A2   N3

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "19N.2.SL.TZ0.S_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

A Gaussian integer is a complex number, z, such that z=a+bi where a,b. In this question, you are asked to investigate certain divisibility properties of Gaussian integers.

\n
\n

Consider two Gaussian integers, α=3+4i and β=1-2i, such that γ=αβ for some Gaussian integer γ.

\n
\n

Now consider two Gaussian integers, α=3+4i and γ=11+2i.

\n
\n

The norm of a complex number z, denoted by Nz, is defined by Nz=z2. For example, if z=2+3i then N2+3i=22+32=13.

\n
\n

A Gaussian prime is a Gaussian integer, z, that cannot be expressed in the form z=αβ where α,β are Gaussian integers with Nα,Nβ>1.

\n
\n

The positive integer 2 is a prime number, however it is not a Gaussian prime.

\n
\n

Let α,β be Gaussian integers.

\n
\n

The result from part (h) provides a way of determining whether a Gaussian integer is a Gaussian prime.

\n
\n

Find γ.

\n
[2]
\n
a.
\n
\n

Determine whether γα is a Gaussian integer.

\n
[3]
\n
b.
\n
\n

On an Argand diagram, plot and label all Gaussian integers that have a norm less than 3.

\n
[2]
\n
c.
\n
\n

Given that α=a+bi where a,b, show that Nα=a2+b2.

\n
[1]
\n
d.
\n
\n

By expressing the positive integer n=c2+d2 as a product of two Gaussian integers each of norm c2+d2, show that n is not a Gaussian prime.

\n
[3]
\n
e.
\n
\n

Verify that 2 is not a Gaussian prime.

\n
[2]
\n
f.
\n
\n

Write down another prime number of the form c2+d2 that is not a Gaussian prime and express it as a product of two Gaussian integers.

\n
[2]
\n
g.
\n
\n

Show that Nαβ=NαNβ.

\n
[6]
\n
h.
\n
\n

Hence show that 1+4i is a Gaussian prime.

\n
[3]
\n
i.
\n
\n

Use proof by contradiction to prove that a prime number, p, that is not of the form a2+b2 is a Gaussian prime.

\n
[6]
\n
j.
\n
", "Markscheme": "
\n

* This sample question was produced by experienced DP mathematics senior examiners to aid teachers in preparing for external assessment in the new MAA course. There may be minor differences in formatting compared to formal exam papers.

\n

3+4i1-2i=11-2i          (M1)A1 

\n

 

\n

[2 marks]

\n
a.
\n
\n

γα=4125-3825i          (M1)A1 

\n

(Since Reγα=4125 and/or Imγα=-3825 are not integers)

\n

γα is not a Gaussian integer         R1

\n

 

\n

Note: Award R1 for correct conclusion from their answer.

\n

 

\n

[3 marks]

\n
b.
\n
\n

±1,±i,0 plotted and labelled        A1

\n

1±i,-1±i plotted and labelled        A1

\n

 

\n

Note: Award A1A0 if extra points to the above are plotted and labelled.

\n

  

\n

[2 marks]

\n
c.
\n
\n

z=a2+b2  (and as Nz=z2)       A1

\n

then N(α)=a2+b2        AG

\n

   

\n

[1 mark]

\n
d.
\n
\n

c2+d2=c+dic-di       A1

\n

and Nc+di=Nc-di=c2+d2       R1

\n

Nc+di,Nc-di>1 (since c,d are positive)       R1

\n

so c2+d2 is not a Gaussian prime, by definition        AG

\n

   

\n

[3 marks]

\n
e.
\n
\n

2=12+12=1+i1-i       (A1)

\n

N1+i=N1-i=2        A1

\n

so 2 is not a Gaussian prime       AG

\n

   

\n

[2 marks]

\n
f.
\n
\n

For example, 5=12+22=1+2i1-2i       (M1)A1

\n

   

\n

[2 marks]

\n
g.
\n
\n

METHOD 1

\n

Let α=m+ni and β=p+qi

\n

LHS:

\n

αβ=mp-nq+mq+npi        M1

\n

Nαβ=mp-nq2+mq+np2       A1

\n

mp2-2mnpq+nq2+mq2+2mnpq+np2       A1

\n

mp2+nq2+mq2+np2       A1

\n

RHS:

\n

NαNβ=m2+n2p2+q2        M1

\n

mp2+mq2+np2+nq2       A1

\n

LHS = RHS and so Nαβ=NαNβ       AG

\n

 

\n

METHOD 2

\n

Let α=m+ni and β=p+qi

\n

LHS

\n

Nαβ=m2+n2p2+q2        M1

\n

=m+nim-nip+qip-qi       A1

\n

=m+nip+qim-nip-qi

\n

=mp-nq+mq+npimp-nq-mq+npi        M1A1

\n

=mp-nq2+mq+np2       A1

\n

N=mp-nq+mq+npi       A1

\n

=NαNβ (= RHS)       AG

\n

   

\n

[6 marks]

\n
h.
\n
\n

N1+4i=17 which is a prime (in )        R1

\n

if 1+4i=αβ then 17=Nαβ=NαNβ        R1

\n

we cannot have Nα,Nβ>1        R1

\n

 

\n

Note: Award R1 for stating that 1+4i is not the product of Gaussian integers of smaller norm because no such norms divide 17

\n

 

\n

so 1+4i is a Gaussian prime        AG

\n

   

\n

[3 marks]

\n
i.
\n
\n

Assume p is not a Gaussian prime

\n

p=αβ where α,β are Gaussian integers and Nα,Nβ>1         M1

\n

Np=NαNβ         M1

\n

p2=NαNβ        A1

\n

It cannot be Nα=1,Nβ=p2 from definition of Gaussian prime        R1

\n

hence Nα=p,Nβ=p        R1

\n

If α=a+bi then Nα=a2+b2=p which is a contradiction        R1

\n

hence a prime number, p, that is not of the form a2+b2 is a Gaussian prime        AG

\n

 

\n

[6 marks]

\n
j.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
\n[N/A]\n
i.
\n
\n[N/A]\n
j.
\n
", "question_id": "EXN.3.AHL.TZ0.2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form", "sl-1-6-simple-proof" ] }, { "Question": "
\n

This question asks you to explore cubic polynomials of the form x-rx2-2ax+a2+b2 for x and corresponding cubic equations with one real root and two complex roots of the form (z-r)(z2-2az+a2+b2)=0 for z.

\n

 

\n
\n

In parts (a), (b) and (c), let r=1, a=4 and b=1.

\n

Consider the equation z-1z2-8z+17=0 for z.

\n
\n

Consider the function fx=x-1x2-8x+17 for x.

\n
\n

Consider the function gx=x-rx2-2ax+a2+b2 for x where r, a and b, b>0.

\n
\n

The equation z-rz2-2az+a2+b2=0 for z has roots r and a±bi where r, a and b, b>0.

\n
\n

On the Cartesian plane, the points C1a, g'a and C2a, -g'a represent the real and imaginary parts of the complex roots of the equation z-rz2-2az+a2+b2=0.

\n


The following diagram shows a particular curve of the form y=x-rx2-2ax+a2+16 and the tangent to the curve at the point Aa, 80. The curve and the tangent both intersect the x-axis at the point R-2, 0. The points C1 and C2 are also shown.

\n

\n
\n

Consider the curve y=(x-r)(x2-2ax+a2+b2) for ar, b>0. The points A(a, g(a)) and R(r, 0) are as defined in part (d)(ii). The curve has a point of inflexion at point P.

\n
\n

Consider the special case where a=r and b>0.

\n
\n

Given that 1 and 4+i are roots of the equation, write down the third root.

\n
[1]
\n
a.i.
\n
\n

Verify that the mean of the two complex roots is 4.

\n
[1]
\n
a.ii.
\n
\n

Show that the line y=x-1 is tangent to the curve y=fx at the point A4, 3.

\n
[4]
\n
b.
\n
\n

Sketch the curve y=f(x) and the tangent to the curve at point A, clearly showing where the tangent crosses the x-axis.

\n
[2]
\n
c.
\n
\n

Show that g'x=2x-rx-a+x2-2ax+a2+b2.

\n
[2]
\n
d.i.
\n
\n

Hence, or otherwise, prove that the tangent to the curve y=gx at the point Aa, ga intersects the x-axis at the point Rr, 0.

\n
[6]
\n
d.ii.
\n
\n

Deduce from part (d)(i) that the complex roots of the equation z-rz2-2az+a2+b2=0 can be expressed as a±ig'a.

\n
[1]
\n
e.
\n
\n

Use this diagram to determine the roots of the corresponding equation of the form z-rz2-2az+a2+16=0 for z.

\n
[4]
\n
f.i.
\n
\n

State the coordinates of C2.

\n
[1]
\n
f.ii.
\n
\n

Show that the x-coordinate of P is 132a+r.

\n

You are not required to demonstrate a change in concavity.

\n
[2]
\n
g.i.
\n
\n

Hence describe numerically the horizontal position of point P relative to the horizontal positions of the points R and A.

\n
[1]
\n
g.ii.
\n
\n

Sketch the curve y=x-rx2-2ax+a2+b2 for a=r=1 and b=2.

\n
[2]
\n
h.i.
\n
\n

For a=r and b>0, state in terms of r, the coordinates of points P and A.

\n
[1]
\n
h.ii.
\n
", "Markscheme": "
\n

4-i        A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

mean=124+i+4-i          A1

\n

=4          AG

\n

  

\n

[1 mark]

\n
a.ii.
\n
\n

METHOD 1

\n

attempts product rule differentiation        (M1)

\n

 

\n

Note: Award (M1) for attempting to express fx as fx=x3-9x2+25x-17

\n

 

\n

f'x=x-12x-8+x2-8x+17  f'x=3x2-18x+25        A1

\n

f'4=1        A1

\n

 

\n

Note: Where f'x is correct, award A1 for solving f'x=1 and obtaining x=4.

\n


EITHER

\n

y-3=1x-4        A1

\n


OR

\n

y=x+c

\n

3=4+cc=-1        A1

\n


OR

\n

states the gradient of y=x-1 is also 1 and verifies that 4, 3 lies on the line y=x-1        A1

\n


THEN

\n

so y=x-1 is the tangent to the curve at A4, 3        AG

\n

 

\n

Note: Award a maximum of (M0)A0A1A1 to a candidate who does not attempt to find f'x.

\n

 

\n

METHOD 2

\n

sets fx=x-1 to form x-1=x-1x2-8x+17        (M1)

\n


EITHER

\n

x-1x2-8x+16=0  x3-9x2+24x-16=0        A1

\n

attempts to solve a correct cubic equation        (M1)

\n

x-1x-42=0x=1, 4

\n


OR

\n

recognises that x1 and forms x2-8x+17=1  x2-8x+16=0        A1

\n

attempts to solve a correct quadratic equation        (M1)

\n

x-42=0x=4

\n


THEN

\n

x=4 is a double root        R1

\n

so y=x-1 is the tangent to the curve at A4, 3        AG

\n

 

\n

Note: Candidates using this method are not required to verify that y=3.

\n

  

\n

[4 marks]

\n
b.
\n
\n

\n

a positive cubic with an  x-intercept x=1, and a local maximum and local minimum in the first quadrant both positioned to the left of A        A1

\n

 

\n

Note: As the local minimum and point A are very close to each other, condone graphs that seem to show these points coinciding.
For the point of tangency, accept labels such as A, 4,3 or the point labelled from both axes. Coordinates are not required.

\n

 

\n

a correct sketch of the tangent passing through A and crossing the x-axis at the same point x=1 as the curve        A1

\n

 

\n

Note: Award A1A0 if both graphs cross the x-axis at distinctly different points.

\n

  

\n

[2 marks]

\n
c.
\n
\n

EITHER

\n

g'x=x-r2x-2a+x2-2ax+a2+b2         (M1)A1

\n


OR

\n

gx=x3-2a+rx2+a2+b2+2arx-a2+b2r

\n

attempts to find g'x        M1

\n

g'x=3x2-22a+rx+a2+b2+2ar

\n

=2x2-2a+rx+2ar+x2-2ax+a2+b2        A1

\n

=2x2-ax-rx+ar+x2-2ax+a2+b2

\n


THEN

\n

g'x=2x-rx-a+x2-2ax+a2+b2        AG

\n

  

\n

[2 marks]

\n
d.i.
\n
\n

METHOD 1

\n

ga=b2a-r         (A1)

\n

g'a=b2         (A1)

\n

attempts to substitute their ga and g'a into y-ga=g'ax-a        M1

\n

y-b2a-r=b2x-a

\n


EITHER

\n

y=b2x-r y=b2x-b2r        A1

\n

sets y=0 so b2x-r=0        M1

\n

b>0x=r OR b0x=r        R1

\n


OR 

\n

sets y=0 so -b2a-r=b2x-a        M1

\n

b>0 OR b0-a-r=x-a        R1

\n

x=r        A1

THEN

\n

so the tangent intersects the x-axis at the point Rr, 0        AG

\n

 

\n

METHOD 2

\n

g'a=b2         (A1)

\n

ga=b2a-r         (A1)

\n

attempts to substitute their ga and g'a into y=g'ax+c and attempts to find c        M1

\n

c=-b2r

\n


EITHER

\n

y=b2x-r y=b2x-b2r        A1

\n

sets y=0 so b2x-r=0        M1

\n

b>0x=r OR b0x=r        R1

\n


OR

\n

sets y=0 so b2x-r=0        M1

\n

b>0 OR b0x-r=0        R1

\n

x=r        A1

\n

 

\n

METHOD 3

\n

g'a=b2         (A1)

\n

the line through Rr, 0 parallel to the tangent at A has equation
y=b2x-r        A1

\n

sets gx=b2x-r to form b2x-r=x-rx2-2ax+a2+b2        M1

\n

b2=x2-2ax+a2+b2, xr        A1

\n

x-a2=0        A1

\n

since there is a double root x=a, this parallel line through Rr, 0 is the required tangent at A        R1

\n

 

\n

[6 marks]

\n
d.ii.
\n
\n

EITHER

\n

g'a=b2b=g'a (since b>0)        R1


Note: Accept b=±g'a.

\n


OR

\n

a±bi=a±ib2 and g'a=b2        R1

\n


THEN

\n

hence the complex roots can be expressed as a±ig'a        AG

\n

 

\n

[1 mark]

\n
e.
\n
\n

b=4 (seen anywhere)        A1

\n


EITHER

\n

attempts to find the gradient of the tangent in terms of a and equates to 16       (M1)


OR

\n

substitutes r=-2, x=a  and  y=80 to form 80=a--2a2-2a2+a2+16       (M1)

\n


OR

\n

substitutes r=-2, x=a  and  y=80 into y=16x-r       (M1)

\n


THEN

\n

80a+2=16a=3

\n

roots are -2 (seen anywhere) and 3±4i        A1A1

\n

 

\n

Note: Award A1 for -2 and A1 for 3±4i. Do not accept coordinates.

\n

 

\n

[4 marks]

\n
f.i.
\n
\n

3, -4        A1

\n

 

\n

Note: Accept “x=3 and y=4”.
Do not award A1FT for (a, 4)

\n

 

\n

[1 mark]

\n
f.ii.
\n
\n

g'x=2x-rx-a+x2-2ax+a2+b2

\n

attempts to find g''x        M1

\n

g''x=2x-a+2x-r+2x-2a =6x-2r-4a

\n

sets g''x=0 and correctly solves for x        A1

\n

for example, obtaining x-r+2x-a=0 leading to 3x=2a+r

\n

so x=132a+r        AG

\n


Note: Do not award A1 if the answer does not lead to the AG.

\n

 

\n

[2 marks]

\n
g.i.
\n
\n

point P is 23 of the horizontal distance (way) from point R to point A       A1

\n


Note: Accept equivalent numerical statements or a clearly labelled diagram displaying the numerical relationship.
Award A0 for non-numerical statements such as “P is between R and A, closer to A”.

\n

 

\n

[1 mark]

\n
g.ii.
\n
\n

y=x-1x2-2x+5       (A1)

\n

\n

a positive cubic with no stationary points and a non-stationary point of inflexion at x=1       A1

\n


Note: Graphs may appear approximately linear. Award this A1 if a change of concavity either side of x=1 is apparent.
Coordinates are not required and the y-intercept need not be indicated.

\n

 

\n

[2 marks]

\n
h.i.
\n
\n

r, 0         A1

\n

 

\n

[1 mark]

\n
h.ii.
\n
", "Examiners report": "
\n

Part (a) (i) was generally well done with a significant majority of candidates using the conjugate root theorem to state 4-i as the third root. A number of candidates, however, wasted considerable time attempting an algebraic method to determine the third root. Part (a) (ii) was reasonably well done. A few candidates however attempted to calculate the product of 4+i and 4-i.

\n

Part (b) was reasonably well done by a significant number of candidates. Most were able to find a correct expression for f'(x) and a good number of those candidates were able to determine that f'(4)=1. Candidates that did not determine the equation of the tangent had to state that the gradient of y=x-1 is also 1 and verify that the point (4,3) lies on the line. A few candidates only met one of those requirements. Weaker candidates tended to only verify that the point (4,3) lies on the curve and the tangent line without attempting to find f'(x).

\n

Part (c) was not answered as well as anticipated. A number of sketches were inaccurate and carelessly drawn with many showing both graphs crossing the x-axis at distinctly different points.

\n

Part (d) (i) was reasonably well done by a good number of candidates. Most successful responses involved use of the product rule. A few candidates obtained full marks by firstly expanding g(x), then differentiating to find g'(x)and finally simplifying to obtain the desired result. A number of candidates made elementary mistakes when differentiating. In general, the better candidates offered reasonable attempts at showing the general result in part (d) (ii). A good number gained partial credit by determining that g'(a)=b2 and/or g(a)=b2(a-r). Only the very best candidates obtained full marks by concluding that as b>0 or b0, then x=r when y=0.

\n

In general, only the best candidates were able to use the result g'(a)=b2 to deduce that the complex roots of the equation can be expressed as a±ig'(a). Although given the complex roots a±bi, a significant number of candidates attempted, with mixed success, to use the quadratic formula to solve the equation z2-2az+a2+b2=0.

\n

In part (f) (i), only a small number of candidates were able to determine all the roots of the equation. Disappointingly, a large number did not state -2 as a root. Some candidates determined that b=4 but were unable to use the diagram to determine that a=3. Of the candidates who determined all the roots in part (f) (i), very few gave the correct coordinates for C2 . The most frequent error was to give the y-coordinate as 3-4i.

\n

Of the candidates who attempted part (g) (i), most were able to find an expression for g''(x) and a reasonable number of these were then able to convincingly show that x=13(2a+r). It was very rare to see a correct response to part (g) (ii). A few candidates stated that P is between R and A with some stating that P was closer to A. A small number restated x=13(2a+r) in words.

\n

Of the candidates who attempted part (h) (i), most were able to determine that y=(x-1)x2-2x+5. However, most graphs were poorly drawn with many showing a change in concavity at x=0 rather than at x=1. In part (h) (ii), only a very small number of candidates determined that A and P coincide at (r,0).

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
\n[N/A]\n
g.i.
\n
\n[N/A]\n
g.ii.
\n
\n[N/A]\n
h.i.
\n
\n[N/A]\n
h.ii.
\n
", "question_id": "22M.3.AHL.TZ1.2", "topics": [ "topic-1-number-and-algebra", "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers", "sl-5-4-tangents-and-normal", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots", "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion", "sl-2-3-graphing" ] }, { "Question": "
\n

This question asks you to investigate some properties of the sequence of functions of the form \n\n\nf\nn\n\n\n(\nx\n)\n=\n\ncos\n\n\n(\n\nn\n\n\narccos\n\n\nx\n\n)\n\n, −1 ≤ \nx\n ≤ 1 and \nn\n\n\n\n\nZ\n\n+\n\n\n.

\n

Important: When sketching graphs in this question, you are not required to find the coordinates of any axes intercepts or the coordinates of any stationary points unless requested.

\n
\n

For odd values of \nn\n > 2, use your graphic display calculator to systematically vary the value of \nn\n. Hence suggest an expression for odd values of \nn\n describing, in terms of \nn\n, the number of

\n
\n

For even values of \nn\n > 2, use your graphic display calculator to systematically vary the value of \nn\n. Hence suggest an expression for even values of \nn\ndescribing, in terms of \nn\n, the number of

\n
\n

The sequence of functions, \n\n\nf\nn\n\n\n(\nx\n)\n, defined above can be expressed as a sequence of polynomials of degree \nn\n.

\n
\n

Consider \n\n\nf\n\nn\n+\n1\n\n\n\n(\nx\n)\n=\n\ncos\n\n\n(\n\n\n(\n\nn\n+\n1\n\n)\n\n\n\narccos\n\n\nx\n\n)\n\n.

\n
\n

On the same set of axes, sketch the graphs of y = f 1 ( x ) and y = f 3 ( x ) for −1 ≤  x ≤ 1.

\n
[2]
\n
a.
\n
\n

local maximum points;

\n
[3]
\n
b.i.
\n
\n

local minimum points;

\n
[1]
\n
b.ii.
\n
\n

On a new set of axes, sketch the graphs of y = f 2 ( x ) and y = f 4 ( x ) for −1 ≤ x ≤ 1.

\n
[2]
\n
c.
\n
\n

local maximum points;

\n
[3]
\n
d.i.
\n
\n

local minimum points.

\n
[1]
\n
d.ii.
\n
\n

Solve the equation f n ( x ) = 0 and hence show that the stationary points on the graph of y = f n ( x ) occur at x = cos k π n where k Z + and 0 < k < n .

\n
[4]
\n
e.
\n
\n

Use an appropriate trigonometric identity to show that f 2 ( x ) = 2 x 2 1 .

\n
[2]
\n
f.
\n
\n

Use an appropriate trigonometric identity to show that  f n + 1 ( x ) = cos ( n arccos x ) cos ( arccos x ) sin ( n arccos x ) sin ( arccos x ) .

\n
[2]
\n
g.
\n
\n

Hence show that  f n + 1 ( x ) + f n 1 ( x ) = 2 x f n ( x ) n Z + .

\n
[3]
\n
h.i.
\n
\n

Hence express f 3 ( x ) as a cubic polynomial.

\n
[2]
\n
h.ii.
\n
", "Markscheme": "
\n

correct graph of y = f 1 ( x )       A1

\n

correct graph of y = f 3 ( x )       A1

\n

\n

[2 marks]

\n
a.
\n
\n

graphical or tabular evidence that n has been systematically varied        M1

\n

eg n = 3, 1 local maximum point and 1 local minimum point

\n

n  = 5, 2 local maximum points and 2 local minimum points

\n

n  = 7, 3 local maximum points and 3 local minimum points        (A1)

\n

n 1 2  local maximum points      A1

\n

[3 marks]

\n
b.i.
\n
\n

n 1 2  local minimum points      A1

\n

Note: Allow follow through from an incorrect local maximum formula expression.

\n

[1 mark]

\n
b.ii.
\n
\n

correct graph of y = f 2 ( x )        A1

\n

correct graph of y = f 4 ( x )        A1

\n

\n

[2 marks]

\n
c.
\n
\n

graphical or tabular evidence that n has been systematically varied       M1

\n

eg n  = 2, 0 local maximum point and 1 local minimum point

\n

n  = 4, 1 local maximum points and 2 local minimum points

\n

n  = 6, 2 local maximum points and 3 local minimum points       (A1)

\n

n 2 2 local maximum points     A1

\n

[3 marks]

\n
d.i.
\n
\n

n 2 local minimum points     A1

\n

[1 mark]

\n
d.ii.
\n
\n

f n ( x ) = cos ( n arccos ( x ) )

\n

f n ( x ) = n sin ( n arccos ( x ) ) 1 x 2       M1A1

\n

Note: Award M1 for attempting to use the chain rule.

\n

f n ( x ) = 0 n sin ( n arccos ( x ) ) = 0      M1

\n

n arccos ( x ) = k π ( k Z + )      A1

\n

leading to

\n

x = cos k π n   ( k Z +  and 0 <  k n )     AG

\n

[4 marks]

\n
e.
\n
\n

f 2 ( x ) = cos ( 2 arccos x )

\n

= 2 ( cos ( arccos x ) ) 2 1      M1

\n

stating that  ( cos ( arccos x ) ) = x      A1

\n

so  f 2 ( x ) = 2 x 2 1      AG

\n

[2 marks]

\n
f.
\n
\n

 

\n

f n + 1 ( x ) = cos ( ( n + 1 ) arccos x )

\n

= cos ( n arccos x + arccos x )      A1

\n

use of cos(A + B) = cos A cos B − sin A sin B leading to      M1

\n

= cos ( n arccos x ) cos ( arccos x ) sin ( n arccos x ) sin ( arccos x )       AG

\n

[2 marks]

\n
g.
\n
\n

f n 1 ( x ) = cos ( ( n 1 ) arccos x )      A1

\n

= cos ( n arccos x ) cos ( arccos x ) + sin ( n arccos x ) sin ( arccos x )     M1

\n

f n + 1 ( x ) + f n 1 ( x ) = 2 cos ( n arccos x ) cos ( arccos x )      A1

\n

= 2 x f n ( x )      AG

\n

[3 marks]

\n
h.i.
\n
\n

f 3 ( x ) = 2 x f 2 ( x ) f 1 ( x )       (M1)

\n

= 2 x ( 2 x 2 1 ) x

\n

= 4 x 3 3 x    A1

\n

[2 marks]

\n
h.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.i.
\n
\n[N/A]\n
h.ii.
\n
", "question_id": "SPM.3.AHL.TZ0.2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

This question investigates the sum of sine and cosine functions

\n
\n

The expression \n3\n\n\nsin\n\n\nx\n+\n4\n\n\ncos\n\n\nx\n can be written in the form \nA\n\n\ncos\n\n(\nB\nx\n+\nC\n)\n+\nD\n, where \nA\n\n,\n\n\n\nB\n\n\n\n\nR\n\n+\n\n\n and \nC\n\n,\n\n\n\nD\n\n\nR\n\n and \n\nπ\n<\nC\n\nπ\n.

\n
\n

The expression \n5\n\n\nsin\n\n\nx\n+\n12\n\n\ncos\n\n\nx\n can be written in the form \nA\n\n\ncos\n\n(\nB\nx\n+\nC\n)\n+\nD\n, where \nA\n\n,\n\n\n\nB\n\n\n\n\nR\n\n+\n\n\n and \nC\n\n,\n\n\n\nD\n\n\nR\n\n and \n\nπ\n<\nC\n\nπ\n.

\n
\n

In general, the expression \na\n\n\nsin\n\n\nx\n+\nb\n\n\ncos\n\n\nx\n can be written in the form \nA\n\n\ncos\n\n(\nB\nx\n+\nC\n)\n+\nD\n, where \na\n\n,\n\n\n\nb\n\n,\n\n\n\nA\n\n,\n\n\n\nB\n\n\n\n\nR\n\n+\n\n\n and \nC\n\n,\n\n\n\nD\n\n\nR\n\n and \n\nπ\n<\nC\n\nπ\n.

\n
\n

Conjecture an expression, in terms of \na\n and \nb\n, for

\n
\n

The expression \na\n\n\nsin\n\n\nx\n+\nb\n\n\ncos\n\n\nx\n can also be written in the form \n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n(\n\n\na\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n\n\nsin\n\n\nx\n+\n\nb\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n\n\ncos\n\n\nx\n\n)\n\n.

\n

Let \n\na\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n\n=\n\nsin\n\n\nθ\n

\n
\n

Sketch the graph \ny\n=\n3\n\n\nsin\n\n\nx\n+\n4\n\n\ncos\n\n\nx\n, for \n\n2\nπ\n\nx\n\n2\nπ\n

\n
[1]
\n
a.i.
\n
\n

Write down the amplitude of this graph

\n
[1]
\n
a.ii.
\n
\n

Write down the period of this graph

\n
[1]
\n
a.iii.
\n
\n

Use your answers from part (a) to write down the value of \nA\n, \nB\n and \nD\n.

\n
[1]
\n
b.i.
\n
\n

Find the value of \nC\n.

\n
[2]
\n
b.ii.
\n
\n

Find \n\narctan\n\n\n3\n4\n\n, giving the answer to 3 significant figures.

\n
[1]
\n
c.i.
\n
\n

Comment on your answer to part (c)(i).

\n
[1]
\n
c.ii.
\n
\n

By considering the graph of \ny\n=\n5\n\n\nsin\n\n\nx\n+\n12\n\n\ncos\n\n\nx\n, find the value of \nA\n\nB\n\nC\n and \nD\n.

\n
[5]
\n
d.
\n
\n

\nA\n.

\n
[1]
\n
e.i.
\n
\n

\nB\n.

\n
[1]
\n
e.ii.
\n
\n

\nC\n.

\n
[1]
\n
e.iii.
\n
\n

\nD\n.

\n
[1]
\n
e.iv.
\n
\n

Show that \n\nb\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n\n=\n\ncos\n\n\nθ\n.

\n
[2]
\n
f.i.
\n
\n

Show that \n\na\nb\n\n=\n\ntan\n\n\nθ\n.

\n
[1]
\n
f.ii.
\n
\n

Hence prove your conjectures in part (e).

\n
[6]
\n
g.
\n
", "Markscheme": "
\n

      A1

\n

[1 mark]

\n
a.i.
\n
\n

5       A1

\n

[1 mark]

\n
a.ii.
\n
\n

\n2\nπ\n      A1

\n

[1 mark]

\n
a.iii.
\n
\n

\nA\n=\n5\n\nB\n=\n1\n\nD\n=\n0\n      A1

\n

[1 mark]

\n
b.i.
\n
\n

maximum at \nx\n=\n0.644\n      M1

\n

So \nC\n=\n\n0.644\n      A1

\n

[2 marks]

\n
b.ii.
\n
\n

0.644      A1

\n

[1 mark]

\n
c.i.
\n
\n

it appears that \nC\n=\n\n\narctan\n\n\n3\n4\n\n      A1

\n

[1 mark]

\n
c.ii.
\n
\n

        M1

\n

\nA\n=\n13\n        A1

\n

\nB\n=\n1\n and \nD\n=\n0\n        A1

\n

maximum at \nx\n=\n0.395\n        M1

\n

So C = −0.395  \n\n(\n\n=\n\n\narctan\n\n\n5\n\n12\n\n\n\n)\n\n      A1

\n

[5 marks]

\n
d.
\n
\n

\nA\n=\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n       A1

\n

[1 mark]

\n
e.i.
\n
\n

\nB\n=\n1\n       A1

\n

[1 mark]

\n
e.ii.
\n
\n

\nC\n=\n\n\narctan\n\n\na\nb\n\n      A1

\n

[1 mark]

\n
e.iii.
\n
\n

\nD\n=\n0\n      A1

\n

[1 mark]

\n
e.iv.
\n
\n

EITHER

\n

use of a right triangle and Pythgoras’ to show the missing side length is \nb\n         M1A1

\n

OR

\n

Use of \n\nsi\n\n\n\n\nn\n\n2\n\n\nθ\n+\n\nco\n\n\n\n\ns\n\n2\n\n\nθ\n=\n1\n, leading to the required result         M1A1

\n

[2 marks]

\n
f.i.
\n
\n

EITHER

\n

use of a right triangle, leading to the required result.         M1

\n

OR

\n

Use of \n\ntan\n\n\nθ\n=\n\n\n\nsin\n\n\nθ\n\n\n\ncos\n\n\nθ\n\n\n, leading to the required result.       M1

\n

[1 mark]

\n
f.ii.
\n
\n

\na\n\n\nsin\n\n\nx\n+\nb\n\n\ncos\n\n\nx\n=\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n(\n\n\nsin\n\n\nθ\n\n\nsin\n\n\nx\n+\n\ncos\n\n\nθ\n\n\ncos\n\n\nx\n\n)\n\n        M1

\n

\na\n\n\nsin\n\n\nx\n+\nb\n\n\ncos\n\n\nx\n=\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n(\n\n\ncos\n\n\n(\n\nx\n\nθ\n\n)\n\n\n)\n\n        M1A1

\n

So \nA\n=\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\nB\n=\n1\n and \nD\n=\n0\n       A1

\n

And \nC\n=\n\nθ\n        M1

\n

So \nC\n=\n\n\narctan\n\n\na\nb\n\n       A1

\n

[6 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
e.iii.
\n
\n[N/A]\n
e.iv.
\n
\n[N/A]\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
\n[N/A]\n
g.
\n
", "question_id": "EXM.3.AHL.TZ0.5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

Consider the function \ng\n\n(\nx\n)\n\n=\n4\n\n\ncos\n\n\nx\n+\n1\n\na\n\nx\n\n\nπ\n2\n\n where \na\n<\n\nπ\n2\n\n.

\n
\n

For  a = π 2 , sketch the graph of  y = g ( x ) . Indicate clearly the maximum and minimum values of the function.

\n
[3]
\n
a.
\n
\n

Write down the least value of a such that g has an inverse.

\n
[1]
\n
b.
\n
\n

For the value of a found in part (b), write down the domain of g 1 .

\n
[1]
\n
c.i.
\n
\n

For the value of a found in part (b), find an expression for g 1 ( x ) .

\n
[2]
\n
c.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

\n

concave down and symmetrical over correct domain       A1

\n

indication of maximum and minimum values of the function (correct range)       A1A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

a = 0      A1

\n

Note: Award A1 for a = 0 only if consistent with their graph.

\n

 

\n

[1 mark]

\n
b.
\n
\n

1 x 5      A1

\n

Note: Allow FT from their graph.

\n

 

\n

[1 mark]

\n
c.i.
\n
\n

y = 4 cos x + 1

\n

x = 4 cos y + 1

\n

x 1 4 = cos y       (M1)

\n

y = arccos ( x 1 4 )

\n

g 1 ( x ) = arccos ( x 1 4 )       A1

\n

 

\n

[2 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "18N.1.AHL.TZ0.H_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-9-reciprocal-trig-ratios-and-their-pythagorean-identities-inverse-circular-functions" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n\n1\n\n1\n\n\n\nx\n2\n\n\n\n\n for \n\n1\n<\nx\n<\n1\n. Use partial fractions to find \n\n\nf\n\n(\nx\n)\n\n\n\n \n\nd\nx\n.

\n
", "Markscheme": "
\n

\n\n1\n\n1\n\n\n\nx\n2\n\n\n\n\n=\n\n1\n\n\n(\n\n1\n\nx\n\n)\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n\n\nA\n\n1\n\nx\n\n\n+\n\nB\n\n1\n+\nx\n\n\n    M1M1A1

\n

\n\n1\n\nA\n\n(\n\n1\n+\nx\n\n)\n\n+\nB\n\n(\n\n1\n\nx\n\n)\n\n\nA\n=\nB\n=\n\n1\n2\n\n     M1A1A1

\n

\n\n\n\n\n\n\n1\n2\n\n\n\n\n1\n\nx\n\n\n\n+\n\n\n\n\n1\n2\n\n\n\n\n1\n+\nx\n\n\nd\nx\n=\n\n\n\n1\n\n2\n\nln\n\n\n(\n\n1\n\nx\n\n)\n\n+\n\n1\n2\n\nln\n\n\n(\n\n1\n+\nx\n\n)\n\n+\nc\n    \n\n(\n\n=\nln\n\nk\n\n\n\n1\n+\nx\n\n\n1\n\nx\n\n\n\n\n)\n\n    M1A1

\n

[8 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "EXM.1.AHL.TZ0.1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-11-partial-fractions" ] }, { "Question": "
\n

Consider the integral \n\n\n1\nt\n\n\n\n\n\n1\n\n\nx\n+\n\n\nx\n2\n\n\n\n\n\n \n\n\nd\nx\n for \nt\n>\n1\n.

\n
\n

Very briefly, explain why the value of this integral must be negative.

\n
[1]
\n
a.
\n
\n

Express the function \nf\n\n(\nx\n)\n\n=\n\n\n\n1\n\n\nx\n+\n\n\nx\n2\n\n\n\n\n in partial fractions.

\n
[6]
\n
b.
\n
\n

Use parts (a) and (b) to show that \n\nln\n\n\n(\n\n1\n+\nt\n\n)\n\n\n\nln\n\n\nt\n<\n\nln\n\n\n2\n.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

The numerator is negative but the denominator is positive. Thus the integrand is negative and so the value of the integral will be negative.     R1AG

\n

[1 mark]

\n
a.
\n
\n

\n\n\n\n1\n\n\nx\n+\n\n\nx\n2\n\n\n\n\n=\n\n\n\n1\n\n\n\n(\n\n1\n+\nx\n\n)\n\nx\n\n\n\n\nA\n\n1\n+\nx\n\n\n+\n\nB\nx\n\n     M1M1A1

\n

\n\n\n1\n\nA\nx\n+\nB\n(\n1\n+\nx\n)\n\nA\n=\n1\n,\n\nB\n=\n\n1\n     M1A1

\n

\n\n\n\n1\n\n\nx\n+\n\n\nx\n2\n\n\n\n\n\n\n1\n\n1\n+\nx\n\n\n+\n\n\n\n1\n\nx\n\n     A1

\n

[6 marks]

\n
b.
\n
\n

\n\n\n1\nt\n\n\n\n1\n\n1\n+\nx\n\n\n+\n\n\n\n1\n\nx\n\nd\nx\n\n=\n\n\n[\n\n\nln\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\nln\n\n\nx\n\n]\n\n1\nt\n\n=\n\nln\n\n\n(\n\n1\n+\nt\n\n)\n\n\n\nln\n\n\nt\n\n\nln\n\n\n2\n    M1A1A1

\n

Hence \n\nln\n\n\n(\n\n1\n+\nt\n\n)\n\n\n\nln\n\n\nt\n\n\nln\n\n\n2\n<\n0\n\n\nln\n\n\n(\n\n1\n+\nt\n\n)\n\n\n\nln\n\n\nt\n<\n\nln\n\n\n2\n     R1AG

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXM.1.AHL.TZ0.2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-11-partial-fractions" ] }, { "Question": "
\n

Consider the rectangle OABC such that AB = OC = 10 and BC = OA = 1 , with the points P , Q and R placed on the line OC such that OP = \np\n, OQ = \nq\n and OR = \nr\n, such that 0 < \np\n < \nq\n < \nr\n < 10.

\n

\n

Let \n\n\nθ\np\n\n\n be the angle APO, \n\n\nθ\nq\n\n\n be the angle AQO and \n\n\nθ\nr\n\n\n be the angle ARO.

\n
\n

Consider the case when \n\n\nθ\np\n\n\n=\n\n\nθ\nq\n\n\n+\n\n\nθ\nr\n\n\n and QR = 1.

\n
\n

Find an expression for  θ p in terms of  p .

\n
[3]
\n
a.
\n
\n

Show that  p = q 2 + q 1 2 q + 1 .

\n
[6]
\n
b.
\n
\n

By sketching the graph of p as a function of q , determine the range of values of p for which there are possible values of q .

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1

\n

use of tan       (M1)

\n

tan θ p = 1 p        (A1)

\n

θ p = arctan ( 1 p )       A1

\n

 

\n

METHOD 2

\n

AP = p 2 + 1       (A1)

\n

use of sin, cos, sine rule or cosine rule using the correct length of AP      (M1)

\n

θ p = arcsin ( 1 p 2 + 1 )   or   θ p = arccos ( p p 2 + 1 )       A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

QR = 1 ⇒  r = q + 1       (A1)

\n

Note: This may be seen anywhere.

\n

 

\n

tan θ p = tan ( θ q + θ r )

\n

attempt to use compound angle formula for tan       M1

\n

tan θ p = tan θ q + tan θ r 1 tan θ q tan θ r       (A1)

\n

1 p = 1 q + 1 r 1 ( 1 q ) ( 1 r )       (M1)

\n

1 p = 1 q + 1 q + 1 1 ( 1 q ) ( 1 q + 1 )   or   p = 1 ( 1 q ) ( 1 q + 1 ) ( 1 q ) + ( 1 q + 1 )       A1

\n

1 p = q + q + 1 q ( q + 1 ) 1        M1

\n

Note: Award M1 for multiplying top and bottom by q ( q + 1 ) .

\n

 

\n

p = q 2 + q 1 2 q + 1        AG

\n

 

\n

[6 marks]

\n
b.
\n
\n

\n

increasing function with positive q -intercept       A1

\n

Note: Accept curves which extend beyond the domain shown above.

\n

 

\n

(0.618 <)  q < 9      (A1)

\n

⇒ range is (0 <) p < 4.68       (A1)

\n

0 < p < 4.68      A1

\n

 

\n

[4 marks]

\n

 

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.2.AHL.TZ0.H_11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n4\nx\n\n5\n\n\n\n\nx\n2\n\n\n\n3\nx\n+\n2\n\n\n     \nx\n\n1\n\n,\n\n\nx\n\n2\n.

\n
\n

Express \nf\n(\nx\n)\n in partial fractions.

\n
[6]
\n
a.
\n
\n

Use part (a) to show that \nf\n(\nx\n)\n is always decreasing.

\n
[3]
\n
b.
\n
\n

Use part (a) to find the exact value of \n\n\n\n\n1\n\n0\n\n\nf\n(\nx\n)\nd\nx\n\n, giving the answer in the form \n\nln\n\n\nq\n,   \nq\n\n\nQ\n\n.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

\nf\n\n(\nx\n)\n\n=\n\n\n4\nx\n\n5\n\n\n\n(\n\nx\n\n1\n\n)\n\n\n(\n\nx\n\n2\n\n)\n\n\n\n\n\nA\n\nx\n\n1\n\n\n+\n\nB\n\nx\n\n2\n\n\n   M1A1

\n

\n\n4\nx\n\n5\n\nA\n\n(\n\nx\n\n2\n\n)\n\n+\nB\n\n(\n\nx\n\n1\n\n)\n\n      M1A1

\n

\nx\n=\n1\n\nA\n=\n1\n      \nx\n=\n2\n\nB\n=\n3\n      A1A1

\n

\nf\n\n(\nx\n)\n\n=\n\n1\n\nx\n\n1\n\n\n+\n\n3\n\nx\n\n2\n\n\n

\n

[6 marks]

\n
a.
\n
\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n\n\n(\n\nx\n\n1\n\n)\n\n\n\n2\n\n\n\n\n3\n\n\n\n(\n\nx\n\n2\n\n)\n\n\n\n2\n\n\n\n   M1A1

\n

This is always negative so function is always decreasing.     R1AG

\n

[3 marks]

\n
b.
\n
\n

\n\n\n\n\n1\n\n0\n\n\n\n1\n\nx\n\n1\n\n\n+\n\n3\n\nx\n\n2\n\n\n\n \n\n\nd\nx\n=\n\n\n[\n\n\nln\n\n\n|\n\nx\n\n1\n\n|\n\n+\n3\n\n\nln\n\n\n|\n\nx\n\n2\n\n|\n\n\n]\n\n\n\n1\n\n0\n\n   M1A1

\n

\n=\n\n(\n\n3\n\n\nln\n\n\n2\n\n)\n\n\n\n(\n\n\n\nln\n\n\n2\n+\n3\n\n\nln\n\n\n3\n\n)\n\n=\n2\n\n\nln\n\n\n2\n\n3\n\n\nln\n\n\n3\n=\n\n\nln\n\n\n4\n\n27\n\n\n    A1A1

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXM.1.AHL.TZ0.3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-11-partial-fractions" ] }, { "Question": "
\n

Find the value of sin π 4 + sin 3 π 4 + sin 5 π 4 + sin 7 π 4 + sin 9 π 4 .

\n
[2]
\n
a.
\n
\n

Show that 1 cos 2 x 2 sin x sin x ,   x k π  where k Z .

\n
[2]
\n
b.
\n
\n

Use the principle of mathematical induction to prove that

\n

sin x + sin 3 x + + sin ( 2 n 1 ) x = 1 cos 2 n x 2 sin x ,   n Z + ,   x k π where k Z .

\n
[9]
\n
c.
\n
\n

Hence or otherwise solve the equation sin x + sin 3 x = cos x  in the interval 0 < x < π .

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

sin π 4 + sin 3 π 4 + sin 5 π 4 + sin 7 π 4 + sin 9 π 4 = 2 2 + 2 2 2 2 2 2 + 2 2 = 2 2    (M1)A1

\n

 

\n

Note: Award M1 for 5 equal terms with \\) + \\) or signs.

\n

 

\n

[2 marks]

\n
a.
\n
\n

1 cos 2 x 2 sin x 1 ( 1 2 sin 2 x ) 2 sin x    M1

\n

2 sin 2 x 2 sin x    A1

\n

sin x    AG

\n

[2 marks]

\n
b.
\n
\n

let  P ( n ) : sin x + sin 3 x + + sin ( 2 n 1 ) x 1 cos 2 n x 2 sin x

\n

if  n = 1

\n

P ( 1 ) : 1 cos 2 x 2 sin x sin x which is true (as proved in part (b))     R1

\n

assume P ( k )  true, sin x + sin 3 x + + sin ( 2 k 1 ) x 1 cos 2 k x 2 sin x      M1

\n

 

\n

Notes: Only award M1 if the words “assume” and “true” appear. Do not award M1 for “let n = k only. Subsequent marks are independent of this M1.

\n

 

\n

consider P ( k + 1 ) :

\n

P ( k + 1 ) : sin x + sin 3 x + + sin ( 2 k 1 ) x + sin ( 2 k + 1 ) x 1 cos 2 ( k + 1 ) x 2 sin x

\n

L H S = sin x + sin 3 x + + sin ( 2 k 1 ) x + sin ( 2 k + 1 ) x    M1

\n

1 cos 2 k x 2 sin x + sin ( 2 k + 1 ) x    A1

\n

1 cos 2 k x + 2 sin x sin ( 2 k + 1 ) x 2 sin x

\n

1 cos 2 k x + 2 sin x cos x sin 2 k x + 2 sin 2 x cos 2 k x 2 sin x    M1

\n

1 ( ( 1 2 sin 2 x ) cos 2 k x sin 2 x sin 2 k x ) 2 sin x    M1

\n

1 ( cos 2 x cos 2 k x sin 2 x sin 2 k x ) 2 sin x    A1

\n

1 cos ( 2 k x + 2 x ) 2 sin x    A1

\n

1 cos 2 ( k + 1 ) x 2 sin x

\n

so if true for n = k , then also true for  n = k + 1

\n

as true for n = 1 then true for all n Z +      R1

\n

 

\n

Note: Accept answers using transformation formula for product of sines if steps are shown clearly.

\n

 

\n

Note: Award R1 only if candidate is awarded at least 5 marks in the previous steps.

\n

 

\n

[9 marks]

\n
c.
\n
\n

EITHER

\n

sin x + sin 3 x = cos x 1 cos 4 x 2 sin x = cos x    M1

\n

1 cos 4 x = 2 sin x cos x ,   ( sin x 0 )    A1

\n

1 ( 1 2 sin 2 2 x ) = sin 2 x    M1

\n

sin 2 x ( 2 sin 2 x 1 ) = 0    M1

\n

sin 2 x = 0  or sin 2 x = 1 2      A1

\n

2 x = π ,   2 x = π 6 and  2 x = 5 π 6

\n

OR

\n

sin x + sin 3 x = cos x 2 sin 2 x cos x = cos x    M1A1

\n

( 2 sin 2 x 1 ) cos x = 0 ,   ( sin x 0 )    M1A1

\n

sin 2 x = 1 2 of cos x = 0     A1

\n

2 x = π 6 ,   2 x = 5 π 6 and  x = π 2

\n

THEN

\n

x = π 2 ,   x = π 12  and x = 5 π 12      A1

\n

 

\n

Note: Do not award the final A1 if extra solutions are seen.

\n

 

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "16N.1.AHL.TZ0.H_13", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule", "sl-3-6-pythagorean-identity-double-angles" ] }, { "Question": "
\n

Explain why any integer can be written in the form \n4\nk\n or \n4\nk\n+\n1\n or \n4\nk\n+\n2\n or \n4\nk\n+\n3\n, where \nk\n\n\nZ\n\n.

\n
[2]
\n
a.
\n
\n

Hence prove that the square of any integer can be written in the form \n4\nt\n or \n4\nt\n+\n1\n, where \nt\n\n\n\n\nZ\n\n+\n\n\n.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

Upon division by 4        M1

\n

any integer leaves a remainder of 0, 1, 2 or 3.      R1

\n

Hence, any integer can be written in the form \n4\nk\n or \n4\nk\n+\n1\n or \n4\nk\n+\n2\n or \n4\nk\n+\n3\n, where \nk\n\n\nZ\n\n      AG

\n

[2 marks]

\n
a.
\n
\n

\n\n\n\n(\n\n4\nk\n\n)\n\n2\n\n\n=\n16\n\n\nk\n2\n\n\n=\n4\nt\n        M1A1

\n

\n\n\n\n(\n\n4\nk\n+\n1\n\n)\n\n2\n\n\n=\n16\n\n\nk\n2\n\n\n+\n8\nk\n+\n1\n=\n4\nt\n+\n1\n        M1A1

\n

\n\n\n\n(\n\n4\nk\n+\n2\n\n)\n\n2\n\n\n=\n16\n\n\nk\n2\n\n\n+\n16\nk\n+\n4\n=\n4\nt\n      A1

\n

\n\n\n\n(\n\n4\nk\n+\n3\n\n)\n\n2\n\n\n=\n16\n\n\nk\n2\n\n\n+\n24\nk\n+\n9\n=\n4\nt\n+\n1\n      A1

\n

Hence, the square of any integer can be written in the form \n4\nt\n or \n4\nt\n+\n1\n, where \nt\n\n\n\n\nZ\n\n+\n\n\n.      AG

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "EXM.1.SL.TZ0.1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-6-simple-proof" ] }, { "Question": "
\n

This question will investigate power series, as an extension to the Binomial Theorem for negative and fractional indices.

\n

A power series in \nx\n is defined as a function of the form \nf\n\n(\nx\n)\n\n=\n\n\na\n0\n\n\n+\n\n\na\n1\n\n\nx\n+\n\n\na\n2\n\n\n\n\nx\n2\n\n\n+\n\n\na\n3\n\n\n\n\nx\n3\n\n\n+\n.\n.\n.\n where the \n\n\na\ni\n\n\n\n\nR\n\n.

\n

It can be considered as an infinite polynomial.

\n
\n

This is an example of a power series, but is only a finite power series, since only a finite number of the \n\n\na\ni\n\n\n are non-zero.

\n
\n

We will now attempt to generalise further.

\n

Suppose \n\n\n\n(\n\n1\n+\nx\n\n)\n\nq\n\n\n\n,\n\n\n\nq\n\n\nQ\n\n can be written as the power series \n\n\na\n0\n\n\n+\n\n\na\n1\n\n\nx\n+\n\n\na\n2\n\n\n\n\nx\n2\n\n\n+\n\n\na\n3\n\n\n\n\nx\n3\n\n\n+\n.\n.\n.\n.

\n
\n

Expand \n\n\n\n(\n\n1\n+\nx\n\n)\n\n5\n\n\n using the Binomial Theorem.

\n
[2]
\n
a.
\n
\n

Consider the power series \n1\n\nx\n+\n\n\nx\n2\n\n\n\n\n\nx\n3\n\n\n+\n\n\nx\n4\n\n\n\n.\n.\n.\n

\n

By considering the ratio of consecutive terms, explain why this series is equal to \n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n1\n\n\n\n and state the values of \nx\n for which this equality is true.

\n
[4]
\n
b.
\n
\n

Differentiate the equation obtained part (b) and hence, find the first four terms in a power series for \n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n2\n\n\n\n.

\n
[2]
\n
c.
\n
\n

Repeat this process to find the first four terms in a power series for \n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n3\n\n\n\n.

\n
[2]
\n
d.
\n
\n

Hence, by recognising the pattern, deduce the first four terms in a power series for \n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\nn\n\n\n\n, \nn\n\n\n\n\nZ\n\n+\n\n\n.

\n
[3]
\n
e.
\n
\n

By substituting \nx\n=\n0\n, find the value of \n\n\na\n0\n\n\n.

\n
[1]
\n
f.
\n
\n

By differentiating both sides of the expression and then substituting \nx\n=\n0\n, find the value of \n\n\na\n1\n\n\n.

\n
[2]
\n
g.
\n
\n

Repeat this procedure to find \n\n\na\n2\n\n\n and \n\n\na\n3\n\n\n.

\n
[4]
\n
h.
\n
\n

Hence, write down the first four terms in what is called the Extended Binomial Theorem for \n\n\n\n(\n\n1\n+\nx\n\n)\n\nq\n\n\n\n,\n\n\n\nq\n\n\nQ\n\n.

\n
[1]
\n
i.
\n
\n

Write down the power series for \n\n1\n\n1\n+\n\n\nx\n2\n\n\n\n\n.

\n
[2]
\n
j.
\n
\n

Hence, using integration, find the power series for \n\narctan\n\n\nx\n, giving the first four non-zero terms.

\n
[4]
\n
k.
\n
", "Markscheme": "
\n

\n1\n+\n5\nx\n+\n10\n\n\nx\n2\n\n\n+\n10\n\n\nx\n3\n\n\n+\n5\n\n\nx\n4\n\n\n+\n\n\nx\n5\n\n\n      M1A1

\n

[2 marks]

\n
a.
\n
\n

It is an infinite GP with \na\n=\n1\n\n,\n\n\n\nr\n=\n\nx\n      R1A1

\n

\n\n\nS\n\n\n\n=\n\n1\n\n1\n\n\n(\n\n\nx\n\n)\n\n\n\n=\n\n1\n\n1\n+\nx\n\n\n=\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n1\n\n\n\n      M1A1AG

\n

[4 marks]

\n
b.
\n
\n

\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n1\n\n\n\n=\n1\n\nx\n+\n\n\nx\n2\n\n\n\n\n\nx\n3\n\n\n+\n\n\nx\n4\n\n\n\n.\n.\n.\n

\n

\n\n1\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n2\n\n\n\n=\n\n1\n+\n2\nx\n\n3\n\n\nx\n2\n\n\n+\n4\n\n\nx\n3\n\n\n\n.\n.\n.\n       A1

\n

\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n2\n\n\n\n=\n1\n\n2\nx\n+\n3\n\n\nx\n2\n\n\n\n4\n\n\nx\n3\n\n\n+\n.\n.\n.\n       A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

\n\n2\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n3\n\n\n\n=\n\n2\n+\n6\nx\n\n12\n\n\nx\n2\n\n\n+\n20\n\n\nx\n3\n\n\n.\n.\n.\n      A1

\n

\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\n3\n\n\n\n=\n1\n\n3\nx\n+\n6\n\n\nx\n2\n\n\n\n10\n\n\nx\n3\n\n\n.\n.\n.\n      A1

\n

[2 marks]

\n
d.
\n
\n

\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\n\nn\n\n\n\n=\n1\n\nn\nx\n+\n\n\nn\n\n(\n\nn\n+\n1\n\n)\n\n\n\n2\n\n!\n\n\n\n\n\nx\n2\n\n\n\n\n\nn\n\n(\n\nn\n+\n1\n\n)\n\n\n(\n\nn\n+\n2\n\n)\n\n\n\n3\n\n!\n\n\n\n\n\nx\n3\n\n\n.\n.\n.\n     A1A1A1

\n

[3 marks]

\n
e.
\n
\n

\n\n\n1\nq\n\n\n=\n\n\na\n0\n\n\n\n\n\na\n0\n\n\n=\n1\n      A1

\n

[1 mark]

\n
f.
\n
\n

\nq\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\nq\n\n1\n\n\n\n=\n\n\na\n1\n\n\n+\n2\n\n\na\n2\n\n\nx\n+\n3\n\n\na\n3\n\n\n\n\nx\n2\n\n\n+\n.\n.\n.\n       A1

\n

\n\n\na\n1\n\n\n=\nq\n       A1

\n

[2 marks]

\n
g.
\n
\n

\nq\n\n(\n\nq\n\n1\n\n)\n\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\nq\n\n2\n\n\n\n=\n1\n×\n2\n\n\na\n2\n\n\n+\n2\n×\n3\n\n\na\n3\n\n\nx\n+\n.\n.\n.\n       A1

\n

\n\n\na\n2\n\n\n=\n\n\nq\n\n(\n\nq\n\n1\n\n)\n\n\n\n2\n\n!\n\n\n\n       A1

\n

\nq\n\n(\n\nq\n\n1\n\n)\n\n\n(\n\nq\n\n2\n\n)\n\n\n\n\n(\n\n1\n+\nx\n\n)\n\n\nq\n\n3\n\n\n\n=\n1\n×\n2\n×\n3\n\n\na\n3\n\n\n+\n.\n.\n.\n       A1

\n

\n\n\na\n3\n\n\n=\n\n\nq\n\n(\n\nq\n\n1\n\n)\n\n\n(\n\nq\n\n2\n\n)\n\n\n\n3\n\n!\n\n\n\n       A1

\n

[4 marks]

\n
h.
\n
\n

\n\n\n\n(\n\n1\n+\nx\n\n)\n\nq\n\n\n=\n1\n+\nq\nx\n+\n\n\nq\n\n(\n\nq\n\n1\n\n)\n\n\n\n2\n\n!\n\n\n\n\n\nx\n2\n\n\n+\n\n\nq\n\n(\n\nq\n\n1\n\n)\n\n\n(\n\nq\n\n2\n\n)\n\n\n\n3\n\n!\n\n\n\n\n\nx\n3\n\n\n.\n.\n.\n     A1

\n

[1 mark]

\n
i.
\n
\n

\n\n1\n\n1\n+\n\n\nx\n2\n\n\n\n\n=\n1\n\n\n\nx\n2\n\n\n+\n\n\nx\n4\n\n\n\n\n\nx\n6\n\n\n+\n.\n.\n.\n    M1A1

\n

[2 marks]

\n
j.
\n
\n

\n\narctan\n\n\nx\n+\nc\n=\nx\n\n\n\n\n\nx\n3\n\n\n\n3\n\n+\n\n\n\n\nx\n5\n\n\n\n5\n\n\n\n\n\n\nx\n7\n\n\n\n7\n\n+\n.\n.\n.\n    M1A1

\n

Putting \nx\n=\n0\n\nc\n=\n0\n        R1

\n

So \n\narctan\n\n\nx\n=\nx\n\n\n\n\n\nx\n3\n\n\n\n3\n\n+\n\n\n\n\nx\n5\n\n\n\n5\n\n\n\n\n\n\nx\n7\n\n\n\n7\n\n+\n.\n.\n.\n        A1

\n

[4 marks]

\n
k.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
\n[N/A]\n
i.
\n
\n[N/A]\n
j.
\n
\n[N/A]\n
k.
\n
", "question_id": "EXM.3.AHL.TZ0.1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n(\nx\n)\n\n \n\n=\n\n \n\n\n(\narcsin\n\n\n \n\nx\n\n)\n2\n\n\n,\n\n \n\n\n1\n\nx\n\n1\n.

\n

 

\n
\n

The function \nf\n satisfies the equation \n\n(\n\n1\n\n\n\nx\n2\n\n\n\n)\n\n\nf\n\n\n\n(\nx\n)\n\n\nx\n\nf\n\n\n\n(\nx\n)\n\n\n2\n=\n0\n.

\n
\n

Show that \n\nf\n\n\n\n(\n0\n)\n\n=\n0\n.

\n
[2]
\n
a.
\n
\n

By differentiating the above equation twice, show that

\n

\n\n(\n\n1\n\n\n\nx\n2\n\n\n\n)\n\n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\nx\n)\n\n\n5\nx\n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\nx\n)\n\n\n4\n\nf\n\n\n\n(\nx\n)\n\n=\n0\n

\n

where \n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\nx\n)\n\n and \n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\nx\n)\n\n denote the 3rd and 4th derivative of \nf\n\n(\nx\n)\n\n respectively.

\n
[4]
\n
b.
\n
\n

Hence show that the Maclaurin series for \nf\n\n(\nx\n)\n\n up to and including the term in \n\n\nx\n4\n\n\n is \n\n\nx\n2\n\n\n+\n\n1\n3\n\n\n\nx\n4\n\n\n.

\n
[3]
\n
c.
\n
\n

Use this series approximation for \nf\n\n(\nx\n)\n\n with \nx\n=\n\n1\n2\n\n to find an approximate value for \n\n\nπ\n2\n\n\n.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n2\n\n\narcsin\n\n\n\n(\nx\n)\n\n\n\n\n1\n\n\n\nx\n2\n\n\n\n\n\n     M1A1

\n

Note: Award M1 for an attempt at chain rule differentiation.
Award M0A0 for \n\nf\n\n\n\n(\nx\n)\n\n=\n2\n\n\narcsin\n\n\n\n(\nx\n)\n\n.

\n

\n\nf\n\n\n\n(\n0\n)\n\n=\n0\n     AG

\n

[2 marks]

\n
a.
\n
\n

differentiating gives \n\n(\n\n1\n\n\n\nx\n2\n\n\n\n)\n\n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\nx\n)\n\n\n2\nx\n\nf\n\n\n\n(\nx\n)\n\n\n\nf\n\n\n\n(\nx\n)\n\n\nx\n\nf\n\n\n\n(\nx\n)\n\n\n(\n\n=\n0\n\n)\n\n      M1A1

\n

differentiating again gives \n\n(\n\n1\n\n\n\nx\n2\n\n\n\n)\n\n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\nx\n)\n\n\n2\nx\n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\nx\n)\n\n\n3\n\nf\n\n\n\n(\nx\n)\n\n\n3\nx\n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\nx\n)\n\n\n\nf\n\n\n\n(\nx\n)\n\n\n(\n\n=\n0\n\n)\n\n     M1A1

\n

Note: Award M1 for an attempt at product rule differentiation of at least one product in each of the above two lines.
Do not penalise candidates who use poor notation.

\n

\n\n(\n\n1\n\n\n\nx\n2\n\n\n\n)\n\n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\nx\n)\n\n\n5\nx\n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\nx\n)\n\n\n4\n\nf\n\n\n\n(\nx\n)\n\n=\n0\n      AG

\n

[4 marks]

\n
b.
\n
\n

attempting to find one of \n\nf\n\n\n\n(\n0\n)\n\n\n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\n0\n)\n\n or \n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\n0\n)\n\n by substituting \nx\n=\n0\n into relevant differential equation(s)       (M1)

\n

Note: Condone \n\nf\n\n\n\n(\n0\n)\n\n found by calculating \n\n\nd\n\n\n\nd\n\nx\n\n\n\n(\n\n\n\n2\n\n\narcsin\n\n\n\n(\nx\n)\n\n\n\n\n1\n\n\n\nx\n2\n\n\n\n\n\n\n)\n\n at \nx\n=\n0\n.

\n

\n\n(\n\nf\n\n(\n0\n)\n\n=\n0\n,\n\n\nf\n\n\n\n(\n0\n)\n\n=\n0\n\n)\n\n

\n

\n\nf\n\n\n\n(\n0\n)\n\n=\n2\n and \n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\n0\n)\n\n\n4\n\nf\n\n\n\n(\n0\n)\n\n=\n0\n\n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\n0\n)\n\n=\n8\n      A1

\n

\n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\n0\n)\n\n=\n0\n and so \n\n2\n\n2\n\n!\n\n\n\n\n\nx\n2\n\n\n+\n\n8\n\n4\n\n!\n\n\n\n\n\nx\n4\n\n\n     A1

\n

Note: Only award the above A1, for correct first differentiation in part (b) leading to \n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\n0\n)\n\n=\n0\n stated or \n\n\nf\n\n\n(\n3\n)\n\n\n\n\n\n(\n0\n)\n\n=\n0\n seen from use of the general Maclaurin series.
Special Case: Award (M1)A0A1 if \n\n\nf\n\n\n(\n4\n)\n\n\n\n\n\n(\n0\n)\n\n=\n8\n is stated without justification or found by working backwards from the general Maclaurin series.

\n

so the Maclaurin series for \nf\n\n(\nx\n)\n\n up to and including the term in \n\n\nx\n4\n\n\n is \n\n\nx\n2\n\n\n+\n\n1\n3\n\n\n\nx\n4\n\n\n     AG

\n

[3 marks]

\n
c.
\n
\n

substituting \nx\n=\n\n1\n2\n\n into \n\n\nx\n2\n\n\n+\n\n1\n3\n\n\n\nx\n4\n\n\n      M1

\n

the series approximation gives a value of \n\n\n13\n\n\n48\n\n\n

\n

so \n\n\nπ\n2\n\n\n\n\n\n13\n\n\n48\n\n\n×\n36\n

\n

\n\n9.75\n\n\n\n(\n\n\n\n\n39\n\n4\n\n\n)\n\n     A1

\n

Note: Accept 9.76.

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18M.3.AHL.TZ0.HCA_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

Note: In this question, distance is in metres and time is in seconds.

\n

A particle P moves in a straight line for five seconds. Its acceleration at time \nt\n is given by \na\n=\n3\n\n\nt\n2\n\n\n\n14\nt\n+\n8\n, for \n0\n\nt\n\n5\n.

\n
\n

When \nt\n=\n0\n, the velocity of P is \n3\n\n m\n\n\n\n\n\ns\n\n\n\n1\n\n\n\n.

\n
\n

Write down the values of \nt\n when \na\n=\n0\n.

\n
[2]
\n
a.
\n
\n

Hence or otherwise, find all possible values of \nt\n for which the velocity of P is decreasing.

\n
[2]
\n
b.
\n
\n

Find an expression for the velocity of P at time \nt\n.

\n
[6]
\n
c.
\n
\n

Find the total distance travelled by P when its velocity is increasing.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nt\n=\n\n2\n3\n\n\n (exact), \n\n0.667\n,\n\n \n\nt\n=\n4\n     A1A1     N2

\n

[2 marks]

\n
a.
\n
\n

recognizing that \nv\n is decreasing when \na\n is negative     (M1)

\n

eg\n\n\n\n\n\n\na\n<\n0\n,\n\n \n\n3\n\n\nt\n2\n\n\n\n14\nt\n+\n8\n\n0\n, sketch of \na\n

\n

correct interval     A1     N2

\n

eg\n\n\n\n\n\n\n\n2\n3\n\n<\nt\n<\n4\n

\n

[2 marks]

\n
b.
\n
\n

valid approach (do not accept a definite integral)     (M1)

\n

eg\n\n\n\n\n\n\nv\n\na\n

\n

correct integration (accept missing \nc\n)     (A1)(A1)(A1)

\n

\n\n\nt\n3\n\n\n\n7\n\n\nt\n2\n\n\n+\n8\nt\n+\nc\n

\n

substituting \nt\n=\n0\n,\n\n \n\nv\n=\n3\n , (must have \nc\n)     (M1)

\n

eg\n\n\n\n\n\n\n3\n=\n\n\n0\n3\n\n\n\n7\n(\n\n\n0\n2\n\n\n)\n+\n8\n(\n0\n)\n+\nc\n,\n\n \n\nc\n=\n3\n

\n

\nv\n=\n\n\nt\n3\n\n\n\n7\n\n\nt\n2\n\n\n+\n8\nt\n+\n3\n     A1     N6

\n

[6 marks]

\n
c.
\n
\n

recognizing that \nv\n increases outside the interval found in part (b)     (M1)

\n

eg\n\n\n\n\n\n\n0\n<\nt\n<\n\n2\n3\n\n,\n\n \n\n4\n<\nt\n<\n5\n, diagram

\n

one correct substitution into distance formula     (A1)

\n

eg\n\n\n\n\n\n\n\n\n0\n\n\n2\n3\n\n\n\n\n\n|\nv\n|\n\n,\n\n \n\n\n\n4\n5\n\n\n\n|\nv\n|\n\n\n,\n\n \n\n\n\n\n\n2\n3\n\n\n4\n\n\n\n|\nv\n|\n\n\n,\n\n \n\n\n\n0\n5\n\n\n\n|\nv\n|\n\n\n\n

\n

one correct pair     (A1)

\n

eg\n\n\n\n\n\n3.13580 and 11.0833, 20.9906 and 35.2097

\n

14.2191     A1     N2

\n

\nd\n=\n14.2\n\n (m)\n\n

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17N.2.SL.TZ0.S_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n\n\nx\n2\n\n\n\nx\n, for \nx\n\n\nR\n\n. The following diagram shows part of the graph of \nf\n.

\n

\"N17/5/MATME/SP1/ENG/TZ0/08\"

\n

The graph of \nf\n crosses the \nx\n-axis at the origin and at the point \n\nP\n\n(\n1\n,\n\n \n\n0\n)\n.

\n
\n

The line \nL\n intersects the graph of \nf\n at another point Q, as shown in the following diagram.

\n

\"N17/5/MATME/SP1/ENG/TZ0/08.c.d\"

\n
\n

Find the area of the region enclosed by the graph of f and the line L .

\n
", "Markscheme": "
\n

valid approach     (M1)

\n

eg L f ,   1 1 ( 1 x 2 ) d x , splitting area into triangles and integrals

\n

correct integration     (A1)(A1)

\n

eg [ x x 3 3 ] 1 1 ,   x 3 3 x 2 2 + x 2 2 + x

\n

substituting their limits into their integrated function and subtracting (in any order)     (M1)

\n

eg 1 1 3 ( 1 1 3 )

\n

 

\n

Note:     Award M0 for substituting into original or differentiated function.

\n

 

\n

area = 4 3     A2     N3

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.SL.TZ0.S_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n\n0.5\n\n\nx\n4\n\n\n+\n3\n\n\nx\n2\n\n\n+\n2\nx\n. The following diagram shows part of the graph of \nf\n.

\n

\"M17/5/MATME/SP2/ENG/TZ2/08\"

\n

 

\n

There are \nx\n-intercepts at \nx\n=\n0\n and at \nx\n=\np\n. There is a maximum at A where \nx\n=\na\n, and a point of inflexion at B where \nx\n=\nb\n.

\n
\n

Find the value of p .

\n
[2]
\n
a.
\n
\n

Write down the coordinates of A.

\n
[2]
\n
b.i.
\n
\n

Write down the rate of change of f  at A.

\n
[1]
\n
b.ii.
\n
\n

Find the coordinates of B.

\n
[4]
\n
c.i.
\n
\n

Find the the rate of change of f at B.

\n
[3]
\n
c.ii.
\n
\n

Let R be the region enclosed by the graph of f , the x -axis, the line x = b and the line x = a . The region R is rotated 360° about the x -axis. Find the volume of the solid formed.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of valid approach     (M1)

\n

eg f ( x ) = 0 ,   y = 0

\n

2.73205

\n

p = 2.73     A1     N2

\n

[2 marks]

\n
a.
\n
\n

1.87938, 8.11721

\n

( 1.88 ,   8.12 )     A2     N2

\n

[2 marks]

\n
b.i.
\n
\n

rate of change is 0 (do not accept decimals)     A1     N1

\n

[1 marks]

\n
b.ii.
\n
\n

METHOD 1 (using GDC)

\n

valid approach     M1

\n

eg f = 0 , max/min on f ,   x = 1

\n

sketch of either f or f , with max/min or root (respectively)     (A1)

\n

x = 1     A1     N1

\n

Substituting their x value into f     (M1)

\n

eg f ( 1 )

\n

y = 4.5     A1     N1

\n

METHOD 2 (analytical)

\n

f = 6 x 2 + 6     A1

\n

setting f = 0     (M1)

\n

x = 1     A1     N1

\n

substituting their x value into f     (M1)

\n

eg f ( 1 )

\n

y = 4.5     A1     N1

\n

[4 marks]

\n
c.i.
\n
\n

recognizing rate of change is f     (M1)

\n

eg y ,   f ( 1 )

\n

rate of change is 6     A1     N2

\n

[3 marks]

\n
c.ii.
\n
\n

attempt to substitute either limits or the function into formula     (M1)

\n

involving f 2 (accept absence of π and/or d x )

\n

eg π ( 0.5 x 4 + 3 x 2 + 2 x ) 2 d x ,   1 1.88 f 2

\n

128.890

\n

volume = 129     A2     N3

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.2.SL.TZ2.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

This question will explore connections between complex numbers and regular polygons.

\n

The diagram below shows a sector of a circle of radius 1, with the angle subtended at the centre \nO\n being \nα\n\n,\n\n\n\n0\n<\nα\n<\n\nπ\n2\n\n. A perpendicular is drawn from point \nP\n to intersect the \nx\n-axis at \nQ\n. The tangent to the circle at \nP\n intersects the \nx\n-axis at \nR\n.

\n

\n
\n

By considering the area of two triangles and the area of the sector show that cos α sin α < α < sin α cos α .

\n
[5]
\n
a.
\n
\n

Hence show that lim α 0 α sin α = 1 .

\n
[2]
\n
b.
\n
\n

Let  z n = 1 , z C , n N , n 5 . Working in modulus/argument form find the n solutions to this equation.

\n
[8]
\n
c.
\n
\n

Represent these n solutions on an Argand diagram. Let their positions be denoted by  P 0 , P 1 , P 2 , P n 1  placed in order in an anticlockwise direction round the circle, starting on the positive x -axis. Show the positions of  P 0 , P 1 , P 2 and  P n 1 .

\n
[1]
\n
d.
\n
\n

Show that the length of the line segment  P 0 P 1 is 2 sin π n .

\n
[4]
\n
e.
\n
\n

Hence, write down the total length of the perimeter of the regular n  sided polygon  P 0 P 1 P 2 P n 1 P 0 .

\n
[1]
\n
f.
\n
\n

Using part (b) find the limit of this perimeter as n .

\n
[2]
\n
g.
\n
\n

Find the total area of this n sided polygon.

\n
[3]
\n
h.
\n
\n

Using part (b) find the limit of this area as n .

\n
[2]
\n
i.
\n
", "Markscheme": "
\n

Area triangle  O P Q = 1 2 cos α sin α        A1

\n

Area sector  = 1 2 1 2 α        A1

\n

Area triangle  O P R = 1 2 1 tan α        A1

\n

So looking at the diagram  1 2 cos α sin α < 1 2 α < 1 2 sin α cos α        M1

\n

cos α sin α < α < sin α cos α        AG

\n

[5 marks]

\n
a.
\n
\n

Hence  cos α < α sin α < 1 cos α and as  α 0 , cos α 1   we have     M1R1

\n

lim α 0 α sin α = 1      AG

\n

[2 marks]

\n
b.
\n
\n

( r c i s θ ) n = 1 c i s 0 r n c i s n θ = 1 c i s θ       M1A1M1A1

\n

r n = 1 r = 1          n θ = 0 + 2 π k , k Z        A1A1

\n

θ = 2 π k n , 0 k n 1        A1

\n

z = c i s 2 π k n , 0 k n 1        A1

\n

[8 marks]

\n
c.
\n
\n

     A1

\n

[1 mark]

\n
d.
\n
\n

Bisecting the triangle  O P 0 P 1 to form two right angle triangles         M1

\n

    

\n

Length of  P 0 P 1 = 2 t where t = sin ( 2 π n 2 )       M1A1A1

\n

So length is  2 sin π n       AG

\n

[4 marks]

\n
e.
\n
\n

Length of perimeter is 2 n sin π n        A1

\n

[1 mark]

\n
f.
\n
\n

2 n sin π n = 2 π n π sin π n 2 π as  n       M1A1

\n

[2 marks]

\n
g.
\n
\n

Area of  O P 0 P 1 = 1 2 1 × 1 sin 2 π n    so total area is  n 2 sin 2 π n .   M1A1A1

\n

[3 marks]

\n
h.
\n
\n

n 2 sin 2 π n = π n 2 π sin 2 π n π as  n       M1A1

\n

[2 marks]

\n
i.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
\n[N/A]\n
i.
\n
", "question_id": "EXM.3.AHL.TZ0.2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form" ] }, { "Question": "
\n

Let g(x) = −(x − 1)2 + 5.

\n
\n

Let f(x) = x2. The following diagram shows part of the graph of f.

\n

\n

The graph of g intersects the graph of f at x = −1 and x = 2.

\n
\n

Write down the coordinates of the vertex of the graph of g.

\n
[1]
\n
a.
\n
\n

On the grid above, sketch the graph of g for −2 ≤ x ≤ 4.

\n
[3]
\n
b.
\n
\n

Find the area of the region enclosed by the graphs of f and g.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(1,5) (exact)      A1 N1

\n

[1 mark]

\n
a.
\n
\n

      A1A1A1  N3

\n

Note: The shape must be a concave-down parabola.
Only if the shape is correct, award the following for points in circles:
A1 for vertex,
A1 for correct intersection points,
A1 for correct endpoints.

\n

[3 marks]

\n
b.
\n
\n

integrating and subtracting functions (in any order)      (M1)
eg  \n\n\nf\n\ng\n\n

\n

correct substitution of limits or functions (accept missing dx, but do not accept any errors, including extra bits)     (A1)
eg \n\n\n\n\n1\n\n2\n\n\ng\n\nf\n,\n\n\n\n\n\n\n\n\n\n(\n\nx\n\n1\n\n)\n\n\n2\n\n\n\n\n+\n5\n\n\n\nx\n2\n\n\n

\n

area = 9  (exact)      A1 N2

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.SL.TZ1.S_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n\nsin\n\n\n\n(\n\n\n\ne\nx\n\n\n\n)\n\n for 0 ≤ \nx\n ≤ 1.5. The following diagram shows the graph of \nf\n.

\n

\n
\n

Find the x-intercept of the graph of \nf\n.

\n
[2]
\n
a.
\n
\n

The region enclosed by the graph of \nf\n, the y-axis and the x-axis is rotated 360° about the x-axis.

\n

Find the volume of the solid formed.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)
eg  \nf\n\n(\nx\n)\n\n=\n0\n,\n\n\n\n\n\n\ne\nx\n\n\n=\n180\n or 0…

\n

1.14472

\n

\nx\n=\n\nln\n\n\nπ\n   (exact), 1.14      A1 N2

\n

[2 marks]

\n
a.
\n
\n

attempt to substitute either their limits or the function into formula involving \n\n\nf\n2\n\n\n.     (M1)

\n

eg  \n\n\n\n0\n\n1.14\n\n\n\n\n\n\nf\n2\n\n\n,\n\n\nπ\n\n\n\n(\n\n\nsin\n\n\n\n(\n\n\n\ne\nx\n\n\n\n)\n\n\n)\n\n\n\n2\n\n\nd\nx\n,\n\n\n0.795135\n

\n

2.49799

\n

volume = 2.50      A2 N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.SL.TZ2.S_3", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Two unbiased tetrahedral (four-sided) dice with faces labelled 1, 2, 3, 4 are thrown and the scores recorded. Let the random variable T be the maximum of these two scores.

\n

The probability distribution of T is given in the following table.

\n

\n
\n

Find the value of a and the value of b.

\n
[3]
\n
a.
\n
\n

Find the expected value of T.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\na\n=\n\n3\n\n16\n\n\n and \nb\n=\n\n5\n\n16\n\n\n     (M1)A1A1

\n

[3 marks]

\n

Note: Award M1 for consideration of the possible outcomes when rolling the two dice.

\n
a.
\n
\n

\n\nE\n\n\n(\nT\n)\n\n=\n\n\n1\n+\n6\n+\n15\n+\n28\n\n\n16\n\n\n=\n\n\n25\n\n8\n\n\n(\n\n=\n3.125\n\n)\n\n     (M1)A1

\n

Note: Allow follow through from part (a) even if probabilities do not add up to 1.

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.AHL.TZ1.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\nln\n\nx\n and \ng\n(\nx\n)\n=\n3\n+\nln\n\n\n(\n\n\nx\n2\n\n\n)\n\n, for \nx\n>\n0\n.

\n

The graph of \ng\n can be obtained from the graph of \nf\n by two transformations:

\n

\n\n\n\n\n\na horizontal stretch of scale factor \n\nq\n\n followed by\n\n\n\n\n\n\n\n\na translation of \n\n\n(\n\n\n\n\nh\n\n\n\n\nk\n\n\n\n\n)\n\n.\n\n\n\n\n

\n
\n

Let \nh\n(\nx\n)\n=\ng\n(\nx\n)\n×\ncos\n\n(\n0.1\nx\n)\n, for \n0\n<\nx\n<\n4\n. The following diagram shows the graph of \nh\n and the line \ny\n=\nx\n.

\n

\"M17/5/MATME/SP2/ENG/TZ1/10.b.c\"

\n

The graph of \nh\n intersects the graph of \n\n\nh\n\n\n1\n\n\n\n at two points. These points have \nx\n coordinates 0.111 and 3.31 correct to three significant figures.

\n
\n

Write down the value of q ;

\n
[1]
\n
a.i.
\n
\n

Write down the value of h ;

\n
[1]
\n
a.ii.
\n
\n

Write down the value of k .

\n
[1]
\n
a.iii.
\n
\n

Find 0.111 3.31 ( h ( x ) x ) d x .

\n
[2]
\n
b.i.
\n
\n

Hence, find the area of the region enclosed by the graphs of h and h 1 .

\n
[3]
\n
b.ii.
\n
\n

Let d be the vertical distance from a point on the graph of h to the line y = x . There is a point P ( a ,   b ) on the graph of h where d is a maximum.

\n

Find the coordinates of P, where 0.111 < a < 3.31 .

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

q = 2     A1     N1

\n

 

\n

Note:     Accept q = 1 , h = 0 , and k = 3 ln ( 2 ) , 2.31 as candidate may have rewritten g ( x ) as equal to 3 + ln ( x ) ln ( 2 ) .

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

h = 0     A1     N1

\n

 

\n

Note:     Accept q = 1 , h = 0 , and k = 3 ln ( 2 ) , 2.31 as candidate may have rewritten g ( x ) as equal to 3 + ln ( x ) ln ( 2 ) .

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

k = 3     A1     N1

\n

 

\n

Note:     Accept q = 1 , h = 0 , and k = 3 ln ( 2 ) , 2.31 as candidate may have rewritten g ( x ) as equal to 3 + ln ( x ) ln ( 2 ) .

\n

 

\n

[1 mark]

\n
a.iii.
\n
\n

2.72409

\n

2.72     A2     N2

\n

[2 marks]

\n
b.i.
\n
\n

recognizing area between y = x and h equals 2.72     (M1)

\n

eg \"M17/5/MATME/SP2/ENG/TZ1/10.b.ii/M\"

\n

recognizing graphs of h and h 1 are reflections of each other in y = x     (M1)

\n

eg area between y = x and h equals between y = x and h 1

\n

2 × 2.72 0.111 3.31 ( x h 1 ( x ) ) d x = 2.72

\n

5.44819

\n

5.45     A1     N3

\n

[??? marks]

\n
b.ii.
\n
\n

valid attempt to find d     (M1)

\n

eg difference in y -coordinates, d = h ( x ) x

\n

correct expression for d     (A1)

\n

eg ( ln 1 2 x + 3 ) ( cos 0.1 x ) x

\n

valid approach to find when d is a maximum     (M1)

\n

eg max on sketch of d , attempt to solve d = 0

\n

0.973679

\n

x = 0.974     A2     N4 

\n

substituting their x value into h ( x )     (M1)

\n

2.26938

\n

y = 2.27     A1     N2

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.SL.TZ1.S_10", "topics": [ "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis", "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

The continuous random variable X has probability density function \nf\n given by

\n

\nf\n\n(\nx\n)\n\n=\n\n{\n\n\n\n\n\n3\na\nx\n\n\n\n,\n\n\n\n0\n\nx\n<\n0.5\n\n\n\n\n\n\na\n\n(\n\n2\n\nx\n\n)\n\n\n\n\n,\n\n\n\n0.5\n\nx\n<\n2\n\n\n\n\n\n0\n\n\n,\n\n\n\n\notherwise\n\n\n\n\n\n\n\n\n

\n

 

\n
\n

Show that  a = 2 3 .

\n
[3]
\n
a.
\n
\n

Find  P ( X < 1 ) .

\n
[3]
\n
b.
\n
\n

Given that P ( s < X < 0.8 ) = 2 × P ( 2 s < X < 0.8 ) , and that 0.25 < s < 0.4 , find the value of s.

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

 

\n

a [ 0 0.5 3 x d x + 0.5 2 ( 2 x ) d x ] = 1      M1

\n

Note: Award the M1 for the total integral equalling 1, or equivalent.

\n

a ( 3 2 ) = 1      (M1)A1

\n

a = 2 3      AG

\n

[3 marks]

\n
a.
\n
\n

EITHER

\n

0 0.5 2 x d x + 2 3 0.5 1 ( 2 x ) d x      (M1)(A1)

\n

= 2 3      A1

\n

OR

\n

2 3 1 2 ( 2 x ) d x = 1 3      (M1)

\n

so  P ( X < 1 ) = 2 3       (M1)A1

\n

[3 marks]

\n
b.
\n
\n

P ( s < X < 0.8 ) = s 0.5 2 x d x + 2 3 0.5 0.8 ( 2 x ) d x      M1A1

\n

= [ x 2 ] s 0.5 + 0.27

\n

0.25 s 2 + 0.27      (A1)

\n

P ( 2 s < X < 0.8 ) = 2 3 2 s 0.8 ( 2 x ) d x      A1

\n

= 2 3 [ 2 x x 2 2 ] 2 s 0.8

\n

2 3 ( 1.28 ( 4 s 2 s 2 ) )

\n

equating

\n

0.25 s 2 + 0.27 = 4 3 ( 1.28 ( 4 s 2 s 2 ) )      (A1)

\n

attempt to solve for s      (M1)

\n

s = 0.274      A1

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.AHL.TZ1.H_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "ahl-4-14-properties-of-discrete-and-continuous-random-variables" ] }, { "Question": "
\n

A continuous random variable \nX\n has probability density function \nf\n given by

\n

\nf\n(\nx\n)\n=\n\n{\n\n\n\n\n\n\n\n\n\nx\n2\n\n\n\na\n\n+\nb\n,\n\n\n\n\n0\n\nx\n\n4\n\n\n\n\n\n0\n\n\n\n\notherwise\n\n\n\n\n\n\n\n\n\nwhere \n\na\n\n and \n\nb\n\n are positive constants.\n\n

\n

It is given that \n\nP\n\n(\nX\n\n2\n)\n=\n0.75\n.

\n
\n

Eight independent observations of \nX\n are now taken and the random variable \nY\n is the number of observations such that \nX\n\n2\n.

\n
\n

Show that a = 32 and b = 1 12 .

\n
[5]
\n
a.
\n
\n

Find E ( X ) .

\n
[2]
\n
b.
\n
\n

Find Var ( X ) .

\n
[2]
\n
c.
\n
\n

Find the median of X .

\n
[3]
\n
d.
\n
\n

Find E ( Y ) .

\n
[2]
\n
e.
\n
\n

Find P ( Y 3 ) .

\n
[1]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

0 4 ( x 2 a + b ) d x = 1 [ x 3 3 a + b x ] 0 4 = 1 64 3 a + 4 b = 1     M1A1

\n

2 4 ( x 2 a + b ) d x = 0.75 56 3 a + 2 b = 0.75     M1A1

\n

 

\n

Note:    0 2 ( x 2 a + b ) d x = 0.25 8 3 a + 2 b = 0.25 could be seen/used in place of either of the above equations.

\n

 

\n

evidence of an attempt to solve simultaneously (or check given a,b values are consistent)     M1

\n

a = 32 ,   b = 1 12      AG

\n

[5 marks]

\n
a.
\n
\n

E ( X ) = 0 4 x ( x 2 32 + 1 12 ) d x     (M1)

\n

E ( X ) = 8 3 ( = 2.67 )      A1

\n

[2 marks]

\n
b.
\n
\n

E ( X 2 ) = 0 4 x 2 ( x 2 32 + 1 12 ) d x      (M1)

\n

Var ( X ) = E ( X 2 ) [ E ( X ) ] 2 = 16 15 ( = 1.07 )      A1

\n

[2 marks]

\n
c.
\n
\n

0 m ( x 2 32 + 1 12 ) d x = 0.5     (M1)

\n

m 3 96 + m 12 = 0.5 ( m 3 + 8 m 48 = 0 )      (A1)

\n

m = 2.91      A1

\n

[3 marks]

\n
d.
\n
\n

Y B ( 8 ,   0.75 )      (M1)

\n

E ( Y ) = 8 × 0.75 = 6      A1

\n

[2 marks]

\n
e.
\n
\n

P ( Y 3 ) = 0.996      A1

\n

[1 mark]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "17M.2.AHL.TZ2.H_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

Write down and simplify the first three terms, in ascending powers of \nx\n, in the Extended Binomial expansion of \n\n\n\n(\n\n1\n\nx\n\n)\n\n\n\n1\n3\n\n\n\n\n.

\n
[3]
\n
a.
\n
\n

By substituting \nx\n=\n\n1\n9\n\n find a rational approximation to \n\n9\n3\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

\n\n\n\n(\n\n1\n\nx\n\n)\n\n\n\n1\n3\n\n\n\n\n=\n1\n+\n\n1\n3\n\n\n(\n\n\nx\n\n)\n\n+\n\n1\n3\n\n\n(\n\n\n\n\n2\n\n3\n\n\n)\n\n\n\n\n\n\n\n(\n\n\nx\n\n)\n\n\n2\n\n\n\n\n2\n\n!\n\n\n\n\n=\n1\n\n\nx\n3\n\n\n\n\n\n\nx\n2\n\n\n\n9\n\n\n       M1A1A1

\n

[3 marks]

\n
a.
\n
\n

\n\n\n\n(\n\n\n8\n9\n\n\n)\n\n\n\n1\n3\n\n\n\n\n\n1\n\n\n1\n\n27\n\n\n\n\n1\n\n729\n\n\n\n\n2\n\n\n9\n3\n\n\n\n\n\n\n701\n\n\n729\n\n\n\n\n9\n3\n\n\n\n\n1458\n\n\n701\n\n\n      M1A1A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "EXM.2.AHL.TZ0.1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n2\nx\n+\n6\n\n\n\n\nx\n2\n\n\n+\n6\nx\n+\n10\n\n\n\n,\n\n\n\nx\n\n\nR\n\n.\n

\n
\n

Show that \nf\n\n(\nx\n)\n\n has no vertical asymptotes.

\n
[3]
\n
a.
\n
\n

Find the equation of the horizontal asymptote. 

\n
[2]
\n
b.
\n
\n

Find the exact value of \n\n\n0\n1\n\n\nf\n\n(\nx\n)\n\n\n\nd\nx\n, giving the answer in the form \n\nln\n\n\nq\n\n,\n\n\n\nq\n\n\nQ\n\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

\n\n\nx\n2\n\n\n+\n6\nx\n+\n10\n=\n\n\nx\n2\n\n\n+\n6\nx\n+\n9\n+\n1\n=\n\n\n\n(\n\nx\n+\n3\n\n)\n\n2\n\n\n+\n1\n      M1A1

\n

So the denominator is never zero and thus there are no vertical asymptotes. (or use of discriminant is negative)       R1

\n

[3 marks]

\n
a.
\n
\n

\nx\n\n±\n\n\n,\n\n\n\nf\n\n(\nx\n)\n\n\n0\n so the equation of the horizontal asymptote is \ny\n=\n0\n   M1A1

\n

[2 marks]

\n
b.
\n
\n

\n\n\n0\n1\n\n\n\n\n2\nx\n+\n6\n\n\n\n\nx\n2\n\n\n+\n6\nx\n+\n10\n\n\n\n\nd\nx\n=\n\n\n[\n\n\nln\n\n\n(\n\n\n\nx\n2\n\n\n+\n6\nx\n+\n10\n\n)\n\n\n]\n\n0\n1\n\n=\n\nln\n\n\n17\n\n\nln\n\n\n10\n=\n\nln\n\n\n\n\n17\n\n\n10\n\n\n      M1A1A1

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXM.1.AHL.TZ0.4", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-13-rational-functions" ] }, { "Question": "
\n

A particle P starts from a point A and moves along a horizontal straight line. Its velocity \nv\n\n cm\n\n\n\n\n\ns\n\n\n\n1\n\n\n\n after \nt\n seconds is given by

\n

\nv\n(\nt\n)\n=\n\n{\n\n\n\n\n\n\n2\nt\n+\n2\n,\n\n\n\n\n\nfor \n\n0\n\nt\n\n1\n\n\n\n\n\n\n3\n\nt\n\n+\n\n4\n\n\n\nt\n2\n\n\n\n\n\n7\n,\n\n\n\n\n\nfor \n\n1\n\nt\n\n12\n\n\n\n\n\n\n\n

\n

The following diagram shows the graph of \nv\n.

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\"N16/5/MATME/SP2/ENG/TZ0/09\"

\n
\n

P is at rest when \nt\n=\n1\n and \nt\n=\np\n.

\n
\n

When \nt\n=\nq\n, the acceleration of P is zero.

\n
\n

Find the initial velocity of \nP\n.

\n
[2]
\n
a.
\n
\n

Find the value of \np\n.

\n
[2]
\n
b.
\n
\n

(i)     Find the value of \nq\n.

\n

(ii)     Hence, find the speed of P when \nt\n=\nq\n.

\n
[4]
\n
c.
\n
\n

(i)     Find the total distance travelled by P between \nt\n=\n1\n and \nt\n=\np\n.

\n

(ii)     Hence or otherwise, find the displacement of P from A when \nt\n=\np\n.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid attempt to substitute \nt\n=\n0\n into the correct function     (M1)

\n

eg\n\n\n\n\n\n\n\n2\n(\n0\n)\n+\n2\n

\n

2     A1     N2

\n

[2 marks]

\n
a.
\n
\n

recognizing \nv\n=\n0\n when P is at rest     (M1)

\n

5.21834

\n

\np\n=\n5.22\n\n \n\n(\n\nseconds\n\n)\n     A1     N2

\n

[2 marks]

\n
b.
\n
\n

(i)     recognizing that \na\n=\n\nv\n\n\n     (M1)

\n

eg\n\n\n\n\n\n\n\nv\n\n\n=\n0\n, minimum on graph

\n

1.95343

\n

\nq\n=\n1.95\n     A1     N2

\n

(ii)     valid approach to find their minimum     (M1)

\n

eg\n\n\n\n\n\n\nv\n(\nq\n)\n,\n\n \n\n\n1.75879\n, reference to min on graph

\n

1.75879

\n

speed \n=\n1.76\n\n \n\n(\nc\n\n\nm\n\n\n\n\n\ns\n\n\n\n1\n\n\n\n)\n     A1     N2

\n

[4 marks]

\n
c.
\n
\n

(i)     substitution of correct \nv\n(\nt\n)\n into distance formula,     (A1)

\n

eg\n\n\n\n\n\n\n\n\n1\np\n\n\n\n|\n\n3\n\nt\n\n+\n\n4\n\n\n\nt\n2\n\n\n\n\n\n7\n\n|\n\n\nd\n\nt\n,\n\n \n\n\n|\n\n\n\n3\n\nt\n\n+\n\n4\n\n\n\nt\n2\n\n\n\n\n\n7\n\nd\n\nt\n\n\n|\n\n\n

\n

4.45368

\n

distance \n=\n4.45\n\n \n\n(\n\ncm\n\n)\n     A1     N2

\n

(ii)     displacement from \nt\n=\n1\n to \nt\n=\np\n (seen anywhere)     (A1)

\n

eg\n\n\n\n\n\n\n\n4.45368\n,\n\n \n\n\n\n1\np\n\n\n\n(\n\n3\n\nt\n\n+\n\n4\n\n\n\nt\n2\n\n\n\n\n\n7\n\n)\n\n\nd\n\nt\n\n

\n

displacement from \nt\n=\n0\n to \nt\n=\n1\n     (A1)

\n

eg\n\n\n\n\n\n\n\n\n0\n1\n\n\n(\n\n2\nt\n+\n2\n)\n\nd\n\nt\n,\n\n \n\n0.5\n×\n1\n×\n2\n,\n\n 1\n\n\n

\n

valid approach to find displacement for \n0\n\nt\n\np\n     M1

\n

eg\n\n\n\n\n\n\n\n\n0\n1\n\n\n(\n\n2\nt\n+\n2\n)\n\nd\n\nt\n+\n\n\n1\np\n\n\n\n(\n\n3\n\nt\n\n+\n\n4\n\n\n\nt\n2\n\n\n\n\n\n7\n\n)\n\n\nd\n\nt\n,\n\n \n\n\n\n0\n1\n\n\n(\n\n2\nt\n+\n2\n)\n\nd\n\nt\n\n4.45\n\n\n\n

\n

\n\n3.45368\n

\n

displacement \n=\n\n3.45\n\n \n\n(\n\ncm\n\n)\n     A1     N2

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "16N.2.SL.TZ0.S_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A particle P moves along a straight line. The velocity v m s−1 of P after t seconds is given by v (t) = 7 cos t − 5t cos t, for 0 ≤ t ≤ 7.

\n

The following diagram shows the graph of v.

\n

\n
\n

Find the initial velocity of P.

\n
[2]
\n
a.
\n
\n

Find the maximum speed of P.

\n
[3]
\n
b.
\n
\n

Write down the number of times that the acceleration of P is 0 m s−2 .

\n
[3]
\n
c.
\n
\n

Find the acceleration of P when it changes direction.

\n
[4]
\n
d.
\n
\n

Find the total distance travelled by P.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

initial velocity when t = 0      (M1)

\n

eg v(0)

\n

v = 7 (m s−1)      A1 N2

\n

[2 marks]

\n
a.
\n
\n

recognizing maximum speed when \n\n|\nv\n|\n\n is greatest      (M1)

\n

eg  minimum, maximum, v' = 0

\n

one correct coordinate for minimum      (A1)

\n

eg  6.37896, −24.6571

\n

24.7 (ms−1)     A1 N2

\n

[3 marks]

\n
b.
\n
\n

recognizing a = v ′     (M1)

\n

eg  \na\n=\n\n\n\nd\n\nv\n\n\n\nd\n\nt\n\n\n, correct derivative of first term

\n

identifying when a = 0      (M1)

\n

eg  turning points of v, t-intercepts of v 

\n

3       A1 N3

\n

[3 marks]

\n
c.
\n
\n

recognizing P changes direction when = 0       (M1)

\n

t = 0.863851      (A1)

\n

−9.24689

\n

a = −9.25 (ms−2)      A2 N3

\n

[4 marks]

\n
d.
\n
\n

correct substitution of limits or function into formula      (A1)
eg   \n\n\n0\n7\n\n\n\n|\n\n\nv\n\n\n|\n\n,\n\n\n\n0\n\n0.8638\n\n\n\nv\n\nd\n\nt\n\n\n\n\n0.8638\n\n7\n\n\nv\n\nd\n\nt\n\n\n,\n\n\n\n\n\n|\n\n\n7\n\n\ncos\n\n\nx\n\n5\n\n\nx\n\n\ncos\n\n\nx\n\n\n\n\n\n|\n\n\n\nd\nx\n,\n\n\n3.32\n=\n60.6\n\n

\n

63.8874

\n

63.9 (metres)      A2 N3

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.2.SL.TZ2.S_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A particle P starts from point O and moves along a straight line. The graph of its velocity, \nv\n ms−1 after \nt\n seconds, for 0 ≤ \nt\n ≤ 6 , is shown in the following diagram.

\n

\n

The graph of \nv\n has \nt\n-intercepts when \nt\n = 0, 2 and 4.

\n

The function \ns\n\n(\nt\n)\n\n represents the displacement of P from O after \nt\n seconds.

\n

It is known that P travels a distance of 15 metres in the first 2 seconds. It is also known that \ns\n\n(\n2\n)\n\n=\ns\n\n(\n5\n)\n\n and \n\n\n2\n4\n\n\nv\n\n\nd\n\nt\n\n=\n9\n.

\n
\n

Find the value of \ns\n\n(\n4\n)\n\n\ns\n\n(\n2\n)\n\n.

\n
[2]
\n
a.
\n
\n

Find the total distance travelled in the first 5 seconds.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognizing relationship between \nv\n and \ns\n      (M1)

\n

eg     \n\n\nv\n=\ns\n\n,  \n\ns\n\n\n=\nv\n

\n

\ns\n\n(\n4\n)\n\n\ns\n\n(\n2\n)\n\n=\n9\n      A1  N2

\n

[2 marks]

\n
a.
\n
\n

correctly interpreting distance travelled in first 2 seconds (seen anywhere, including part (a) or the area of 15 indicated on diagram)        (A1)

\n

eg    \n\n\n0\n2\n\n\nv\n=\n15\n\n\ns\n\n(\n2\n)\n\n=\n15\n

\n

valid approach to find total distance travelled       (M1)

\n

eg    sum of 3 areas,  \n\n\n0\n4\n\n\nv\n+\n\n\n\n4\n5\n\nv\n,  shaded areas in diagram between 0 and 5

\n

Note: Award M0 if only \n\n\n0\n5\n\n\n\n|\nv\n|\n\n\n is seen.

\n

correct working towards finding distance travelled between 2 and 5 (seen anywhere including within total area expression or on diagram)       (A1)

\n

eg   \n\n\n2\n4\n\n\nv\n\n\n\n\n4\n5\n\nv\n,  \n\n\n2\n4\n\n\nv\n=\n\n\n\n4\n5\n\n\n\n|\nv\n|\n\n\n,  \n\n\n4\n5\n\n\nv\n\n\nd\n\nt\n\n=\n\n9\n,  \ns\n\n(\n4\n)\n\n\ns\n\n(\n2\n)\n\n\n\n[\n\ns\n\n(\n5\n)\n\n\ns\n\n(\n4\n)\n\n\n]\n\n,

\n

equal areas 

\n

correct working using \ns\n\n(\n5\n)\n\n=\ns\n\n(\n2\n)\n\n      (A1)

\n

eg   \n15\n+\n9\n\n\n(\n\n\n9\n\n)\n\n,  \n15\n+\n2\n\n[\n\ns\n\n(\n4\n)\n\n\ns\n\n(\n2\n)\n\n\n]\n\n,  \n15\n+\n2\n\n(\n9\n)\n\n,  \n2\n×\ns\n\n(\n4\n)\n\n\ns\n\n(\n2\n)\n\n,  \n48\n\n15\n

\n

total distance travelled = 33 (m)        A1   N2

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.SL.TZ1.S_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

This question will investigate methods for finding definite integrals of powers of trigonometrical functions.

\n

Let \n\n\nI\nn\n\n\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\nsi\n\n\n\n\nn\n\nn\n\n\n\nx\n\nd\nx\n\n,\n\n\n\nn\n\n\nN\n\n.

\n

 

\n
\n

Let \n\n\nJ\nn\n\n\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\nco\n\n\n\n\ns\n\nn\n\n\n\nx\n\nd\nx\n\n,\n\n\n\nn\n\n\nN\n\n.\n

\n
\n

Let \n\n\nT\nn\n\n\n=\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\nn\n\n\n\nx\n\nd\nx\n\n,\n\n\n\nn\n\n\nN\n\n.

\n
\n

Find the exact values of \n\n\nI\n0\n\n\n\n\n\nI\n1\n\n\n and \n\n\nI\n2\n\n\n.

\n
[6]
\n
a.
\n
\n

Use integration by parts to show that \n\n\nI\nn\n\n\n=\n\n\nn\n\n1\n\nn\n\n\n\nI\n\nn\n\n2\n\n\n\n\n,\n\n\n\nn\n\n2\n.

\n
[5]
\n
b.i.
\n
\n

Explain where the condition \nn\n\n2\n was used in your proof.

\n
[1]
\n
b.ii.
\n
\n

Hence, find the exact values of \n\n\nI\n3\n\n\n and \n\n\nI\n4\n\n\n.

\n
[2]
\n
c.
\n
\n

Use the substitution \nx\n=\n\nπ\n2\n\n\nu\n to show that \n\n\nJ\nn\n\n\n=\n\n\nI\nn\n\n\n.

\n
[4]
\n
d.
\n
\n

Hence, find the exact values of \n\n\nJ\n\n5\n\n\n\n and \n\n\nJ\n\n6\n\n\n\n

\n
[2]
\n
e.
\n
\n

Find the exact values of \n\n\nT\n\n0\n\n\n\n and \n\n\nT\n\n1\n\n\n\n.

\n
[3]
\n
f.
\n
\n

Use the fact that \n\nta\n\n\n\n\nn\n\n2\n\n\nx\n=\n\nse\n\n\n\n\nc\n\n2\n\n\nx\n\n1\n to show that \n\n\nT\nn\n\n\n=\n\n1\n\nn\n\n1\n\n\n\n\n\nT\n\nn\n\n2\n\n\n\n\n,\n\n\n\nn\n\n2\n.

\n
[3]
\n
g.i.
\n
\n

Explain where the condition \nn\n\n2\n was used in your proof.

\n
[1]
\n
g.ii.
\n
\n

Hence, find the exact values of \n\n\nT\n\n2\n\n\n\n and \n\n\nT\n\n3\n\n\n\n.

\n
[2]
\n
h.
\n
", "Markscheme": "
\n

\n\n\nI\n0\n\n\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n1\n\nd\nx\n=\n\n\n[\nx\n]\n\n0\n\n\n\nπ\n2\n\n\n\n\n=\n\nπ\n2\n\n      M1A1

\n

\n\n\nI\n1\n\n\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\nsin\n\n\nx\n\n\nd\nx\n=\n\n\n[\n\n\n\ncos\n\n\nx\n\n]\n\n0\n\n\n\nπ\n2\n\n\n\n\n=\n1\n      M1A1

\n

\n\n\nI\n2\n\n\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\nsi\n\n\n\n\nn\n\n2\n\n\nx\n\n\nd\nx\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\n\n1\n\n\ncos\n\n\n2\nx\n\n2\n\n\n\nd\nx\n=\n\n\n[\n\n\nx\n2\n\n\n\n\n\nsin\n\n\n2\nx\n\n4\n\n\n]\n\n0\n\n\n\nπ\n2\n\n\n\n\n=\n\nπ\n4\n\n      M1A1

\n

[6 marks]

\n
a.
\n
\n

\n\nu\n=\n\nsi\n\n\n\n\nn\n\n\nn\n\n1\n\n\n\nx\n\n                               \n\nv\n=\n\ncos\n\nx\n\n

\n

\n\n\n\nd\nu\n\n\nd\nx\n\n\n=\n\n(\n\nn\n\n1\n\n)\n\n\nsi\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\nx\n\n\ncos\n\n\nx\n\n     \n\n\n\nd\nv\n\n\nd\nx\n\n\n=\n\nsin\n\n\nx\n\n

\n

\n\n\nI\nn\n\n\n=\n\n\n[\n\n\n\nsi\n\n\n\n\nn\n\n\nn\n\n1\n\n\n\nx\n\n\ncos\n\n\nx\n\n]\n\n0\n\n\n\nπ\n2\n\n\n\n\n+\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\n(\n\nn\n\n1\n\n)\n\n\nsi\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\nx\n\n\ncos\n\n\n\n\n2\n\n\nx\n\n\nd\nx\n      M1A1A1

\n

\n=\n0\n+\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\n(\n\nn\n\n1\n\n)\n\n\nsi\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\nx\n\n(\n\n1\n\n\nsi\n\n\n\n\nn\n\n2\n\n\nx\n\n)\n\n\n\nd\nx\n=\n\n(\n\nn\n\n1\n\n)\n\n\n(\n\n\n\nI\n\nn\n\n2\n\n\n\n\n\n\nI\nn\n\n\n\n)\n\n      M1A1

\n

\n\nn\n\n\nI\nn\n\n\n=\n\n(\n\nn\n\n1\n\n)\n\n\n\nI\n\nn\n\n2\n\n\n\n\n\n\nI\nn\n\n\n=\n\n\n\n(\n\nn\n\n1\n\n)\n\n\nn\n\n\n\nI\n\nn\n\n2\n\n\n\n        AG

\n

[6 marks]

\n
b.i.
\n
\n

need \nn\n\n2\n so that \n\nsi\n\n\n\n\nn\n\n\nn\n\n1\n\n\n\n\n\nπ\n2\n\n\n=\n0\n in \n\n\n[\n\n\n\nsi\n\n\n\n\nn\n\n\nn\n\n1\n\n\n\n\nx\n\n\ncos\n\n\nx\n\n]\n\n0\n\n\n\nπ\n2\n\n\n\n\n       R1

\n

[1 mark]

\n
b.ii.
\n
\n

\n\n\nI\n3\n\n\n=\n\n2\n3\n\n\n\nI\n1\n\n\n=\n\n2\n3\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nI\n4\n\n\n=\n\n3\n4\n\n\n\nI\n2\n\n\n=\n\n\n3\nπ\n\n\n16\n\n\n      A1A1

\n

[2 marks]

\n
c.
\n
\n

\nx\n=\n\nπ\n2\n\n\nu\n\n\n\nd\nx\n\n\nd\nu\n\n\n=\n\n1\n      A1

\n

\n\n\nJ\nn\n\n\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\nco\n\n\n\n\ns\n\nn\n\n\n\nx\n\nd\nx\n\n\n=\n\n\n\n\n\nπ\n2\n\n\n\n0\n\n\n\n\nco\n\n\n\n\ns\n\nn\n\n\n\n\n(\n\n\nπ\n2\n\n\nu\n\n)\n\n\nd\nu\n=\n\n\n\n\n\n\nπ\n2\n\n\n\n0\n\n\n\nsi\n\n\n\n\nn\n\nn\n\n\n\nu\n\nd\nu\n\n=\n\n\n0\n\n\n\nπ\n2\n\n\n\n\n\n\nsi\n\n\n\n\nn\n\nn\n\n\n\nu\n\nd\nu\n\n=\n\n\nI\nn\n\n\n      M1A1A1AG

\n

[4 marks]

\n
d.
\n
\n

\n\n\nJ\n5\n\n\n=\n\n\nI\n5\n\n\n=\n\n4\n5\n\n\n\nI\n3\n\n\n=\n\n4\n5\n\n×\n\n2\n3\n\n=\n\n8\n\n15\n\n\n\n\n\n\n\n\n\n\n\n\n\n\nJ\n6\n\n\n=\n\n\nI\n6\n\n\n=\n\n5\n6\n\n\n\nI\n4\n\n\n=\n\n5\n6\n\n×\n\n\n3\nπ\n\n\n16\n\n\n=\n\n\n5\nπ\n\n\n32\n\n\n     A1A1

\n

[2 marks]

\n
e.
\n
\n

\n\n\nT\n\n0\n\n\n\n\n\n = \n\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n1\n\nd\nx\n\n=\n\n\n[\nx\n]\n\n0\n\n\n\nπ\n4\n\n\n\n\n=\n\nπ\n4\n\n      A1

\n

\n\n\nT\n\n1\n\n\n\n\n\n = \n\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\ntan\n\n\nd\nx\n\n=\n\n\n[\n\n\nln\n\n\n|\n\n\ncos\n\n\nx\n\n|\n\n\n]\n\n0\n\n\n\nπ\n4\n\n\n\n\n=\n\n\nln\n\n\n1\n\n\n2\n\n\n\n=\n\nln\n\n\n2\n\n       M1A1

\n

[3 marks]

\n
f.
\n
\n

\n\n\nT\nn\n\n\n=\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\nn\n\n\n\nx\n\nd\nx\n\n=\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\n\nx\n\n\nta\n\n\n\n\nn\n\n2\n\n\nx\n\nd\nx\n\n=\n\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\n\nx\n\n(\n\n\nse\n\n\n\n\nc\n\n2\n\n\nx\n\n1\n\n)\n\n\nd\nx\n         M1

\n

\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\n\nx\n\n\nse\n\n\n\n\nc\n\n2\n\n\nx\n\nd\nx\n\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\n\nx\n\nd\nx\n=\n\n\n[\n\n\n\n\nta\n\n\n\n\nn\n\n\nn\n\n1\n\n\n\nx\n\n\nn\n\n1\n\n\n\n]\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\n\nT\n\nn\n\n2\n\n\n\n=\n\n1\n\nn\n\n1\n\n\n\n\n\nT\n\nn\n\n2\n\n\n\n\n\n\n        A1A1AG

\n

[3 marks]

\n
g.i.
\n
\n

need \nn\n\n2\n so that the powers of tan in \n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\n\nx\n\n\nse\n\n\n\n\nc\n\n2\n\n\nx\n\nd\nx\n\n\n\n0\n\n\n\nπ\n4\n\n\n\n\n\n\nta\n\n\n\n\nn\n\n\nn\n\n2\n\n\n\n\nx\n\nd\nx\n are not negative         R1   

\n

 

\n

[1 mark]

\n
g.ii.
\n
\n

\n\n\nT\n2\n\n\n=\n1\n\n\n\nT\n0\n\n\n=\n1\n\n\nπ\n4\n\n         A1 

\n

\n\n\nT\n3\n\n\n=\n\n1\n2\n\n\n\n\nT\n1\n\n\n=\n\n1\n2\n\n\nln\n\n\n2\n\n         A1

\n

[2 marks]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.i.
\n
\n[N/A]\n
g.ii.
\n
\n[N/A]\n
h.
\n
", "question_id": "EXM.3.AHL.TZ0.3", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

Consider \nf\n(\nx\n)\n=\n\nx\n\n\n\nsin\n\n\n(\n\n\nπ\n4\n\nx\n\n)\n\n and \ng\n(\nx\n)\n=\n\nx\n\n for \nx\n ≥ 0. The first time the graphs of \nf\n and \ng\n intersect is at \nx\n=\n0\n.

\n
\n

The set of all non-zero values that satisfy \nf\n(\nx\n)\n=\ng\n(\nx\n)\n can be described as an arithmetic sequence, \n\n\nu\nn\n\n\n=\na\n+\nb\nn\n where \nn\n ≥ 1.

\n
\n

Find the two smallest non-zero values of x for which f ( x ) = g ( x ) .

\n
[5]
\n
a.
\n
\n

At point P, the graphs of f and g intersect for the 21st time. Find the coordinates of P.

\n
[4]
\n
c.
\n
\n

The following diagram shows part of the graph of g reflected in the x -axis. It also shows part of the graph of f and the point P.

\n

\n

Find an expression for the area of the shaded region. Do not calculate the value of the expression.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct working        (A1)

\n

eg    sin ( π 4 x ) = 1 ,   x ( 1 sin ( π 4 x ) ) = 0

\n

sin ( π 2 ) = 1   (seen anywhere)        (A1)

\n

correct working (ignore additional values)        (A1)

\n

eg    π 4 x = π 2 ,   π 4 x = π 2 + 2 π

\n

x = 2, 10       A1A1    N1N1

\n

[5 marks]

\n
a.
\n
\n

valid approach        (M1)

\n

eg     first intersection at  x = 0 n = 20

\n

correct working        A1

\n

eg    6 + 8 × 20 ,   2 + ( 20 1 ) × 8 , u 20 = 154

\n

P(154,  154 )   (accept  x = 154 and  y = 154 )      A1A1    N3

\n

[4 marks]

\n
c.
\n
\n

valid attempt to find upper boundary         (M1)

\n

eg    half way between u 20 and u 21 , u 20 + d 2 , 154 + 4,  2 + 8 n , at least two values of new sequence {6, 14, ...}

\n

upper boundary at  x = 158 (seen anywhere)        (A1)

\n

correct integral expression (accept missing d x )    A1A1    N4

\n

eg    0 158 ( x sin ( π 4 x ) + x ) d x 0 158 ( g + f ) d x ) ,   0 158 x sin ( π 4 x ) d x 0 158 x d x

\n

Note: Award A1 for two correct limits and A1 for correct integrand. The A1 for correct integrand may be awarded independently of all the other marks.

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.1.SL.TZ1.S_10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Steffi the stray cat often visits Will’s house in search of food. Let \nX\n be the discrete random variable “the number of times per day that Steffi visits Will’s house”.

\n

The random variable \nX\n can be modelled by a Poisson distribution with mean 2.1.

\n
\n

Let Y be the discrete random variable “the number of times per day that Steffi is fed at Will’s house”. Steffi is only fed on the first four occasions that she visits each day.

\n
\n

Find the probability that on a randomly selected day, Steffi does not visit Will’s house.

\n
[2]
\n
a.
\n
\n

Copy and complete the probability distribution table for Y.

\n

\n
[4]
\n
b.
\n
\n

Hence find the expected number of times per day that Steffi is fed at Will’s house.

\n
[3]
\n
c.
\n
\n

In any given year of 365 days, the probability that Steffi does not visit Will for at most \nn\n days in total is 0.5 (to one decimal place). Find the value of \nn\n.

\n
[3]
\n
d.
\n
\n

Show that the expected number of occasions per year on which Steffi visits Will’s house and is not fed is at least 30.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nX\n\n\nPo\n\n\n(\n\n2.1\n\n)\n\n

\n

\n\nP\n\n\n(\n\nX\n=\n0\n\n)\n\n=\n0.122\n\n(\n\n=\n\n\n\ne\n\n\n\n2.1\n\n\n\n\n)\n\n       (M1)A1

\n

[2 marks]

\n
a.
\n
\n

      A1A1A1A1

\n

Note: Award A1 for each correct probability for Y = 1, 2, 3, 4. Accept 0.162 for P(Y = 4).

\n

[4 marks]

\n
b.
\n
\n

\n\nE\n\n\n(\nY\n)\n\n=\n\n\ny\n\nP\n\n\n(\n\nY\n=\ny\n\n)\n\n\n      (M1)

\n

\n=\n1\n×\n0.257\n\n+\n2\n×\n0.270\n\n+\n3\n×\n0.189\n+\n4\n×\n0.161\n\n      (A1)

\n

\n=\n2.01\n      A1

\n

[3 marks]

\n
c.
\n
\n

let \nT\n be the no of days per year that Steffi does not visit

\n

\nT\n\nB\n\n(\n\n365\n\n,\n\n\n\n0.122\n\n\n)\n\n      (M1)

\n

require \n0.45\n\n\nP\n\n\n(\n\nT\n\nn\n\n)\n\n<\n0.55\n      (M1)

\n

\n\nP\n\n\n(\n\nT\n\n44\n\n)\n\n=\n0.51\n

\n

\nn\n=\n44\n      A1

\n

[3 marks]

\n
d.
\n
\n

METHOD 1

\n

let \nV\n be the discrete random variable “number of times Steffi is not fed per day”

\n

\n\nE\n\n\n(\nV\n)\n\n=\n1\n×\n\nP\n\n\n(\n\nX\n=\n5\n\n)\n\n+\n2\n×\n\nP\n\n\n(\n\nX\n=\n6\n\n)\n\n+\n3\n×\n\nP\n\n\n(\n\nX\n=\n7\n\n)\n\n+\n\n        M1

\n

\n=\n1\n×\n0.0416\n\n+\n2\n×\n0.0145\n\n+\n3\n×\n0.00437\n\n+\n\n      A1

\n

= 0.083979...      A1

\n

expected no of occasions per year > 0.083979... × 365 = 30.7      A1

\n

hence Steffi can expect not to be fed on at least 30 occasions       AG

\n

Note: Candidates may consider summing more than three terms in their calculation for \n\nE\n\n\n(\nV\n)\n\n.

\n

 

\n

METHOD 2

\n

\n\nE\n\n\n(\nX\n)\n\n\n\nE\n\n\n(\nY\n)\n\n=\n0.0903\n\n       M1A1

\n

0.0903… × 365       M1

\n

= 33.0 > 30       A1AG

\n

  

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "19M.2.AHL.TZ2.H_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Olivia’s house consists of four vertical walls and a sloping roof made from two rectangles. The height, \n\nCD\n\n, from the ground to the base of the roof is 4.5 m.

\n

The base angles of the roof are \n\nA\n\n\n\nB\n\n\n\n\n\nC\n\n=\n\n27\n\n\n and \n\nA\n\n\n\nC\n\n\n\n\n\nB\n\n=\n\n26\n\n\n.

\n

\n

The house is 10 m long and 5 m wide.

\n
\n

The length \n\nAC\n\n is approximately 2.84 m.

\n
\n

Olivia decides to put solar panels on the roof. The solar panels are fitted to both sides of the roof.

\n

\n

Each panel is 1.6 m long and 0.95 m wide. All the panels must be arranged in uniform rows, with the shorter edge of each panel parallel to \n\nAB\n\n or \n\nAC\n\n. Each panel must be at least 0.3 m from the edge of the roof and the top of the roof, \n\nAF\n\n.

\n
\n

Olivia estimates that the solar panels will cover an area of 29 m2.

\n
\n

Find the length \n\nAB\n\n, giving your answer to four significant figures.

\n
[5]
\n
a.
\n
\n

Find the total area of the two rectangles that make up the roof.

\n
[3]
\n
b.
\n
\n

Find the maximum number of complete panels that can be fitted to the whole roof.

\n
[3]
\n
c.
\n
\n

Find the percentage error in her estimate.

\n
[3]
\n
d.
\n
\n

Olivia investigates arranging the panels, such that the longer edge of each panel is parallel to \n\nAB\n\n or \n\nAC\n\n.

State whether this new arrangement will allow Olivia to fit more solar panels to the roof. Justify your answer.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

180° − 27° − 26°      (M1)

\n

Note: Award (M1) for correct working to find angle \n\nB\n\n\n\nA\n\n\n\n\n\nC\n\n or 127 seen.

\n

\n\n\n\nAB\n\n\n\n\nsin\n\n\n\n26\n\n\n\n\n=\n\n5\n\n\nsin\n\n\n\n127\n\n\n\n\n       (M1)(A1)

\n

Note: Award (M1) for substitution into sine rule formula and (A1) for correct substitution.

\n

2.74450 (m)      (A1)

\n

(\n\nAB\n\n =) 2.745 (m)      (A1)(ft)(G4)

\n

Note: The final (A1)(ft) is for correctly rounding their unrounded \n\nAB\n\n to 4 sf. If 2.745 is given as the final answer, the unrounded answer need not be seen, award (M1)(M1)(A1)(A2). For all other answers, the unrounded answer must be seen to an accuracy greater than 4 sf.

\n

Award (G3) for a final answer of 2.74450…(m) with no working. If radians are used then award at most (M1)(M1)(A1)(A0)(A1)(ft) for an answer of 3.920 (m).

\n

[5 marks]

\n
a.
\n
\n

Units are required in this question part.

\n

 

\n

10 × 2.84 + 10 × 2.74450…       (M1)(M1)

\n

Note: Award (M1) for finding their area of each rectangle and (M1) for adding their areas.

\n

OR

\n

10 × (2.84 + 2.74450…)       (M1)(M1)

\n

Note: Award (M1) for adding \n\nAC\n\n and their \n\nAB\n\n. Award (M1) for multiplying their total area by 10.

\n

55.8 (55.8450…) m2       (A1)(ft)(G3)

\n

Note: Follow through from their \n\nAB\n\n in part (a).

\n

[3 marks]

\n
b.
\n
\n

\n\n\n10\n\n2\n\n(\n\n0.3\n\n)\n\n\n\n1.6\n\n\n      (M1)

\n

Note: Award (M1) for correct calculation of the number of panels on the long side.

\n

\n\n\n2.745\n\n2\n\n(\n\n0.3\n\n)\n\n\n\n0.95\n\n\n  OR  \n\n\n2.84\n\n2\n\n(\n\n0.3\n\n)\n\n\n\n0.95\n\n\n      (M1)

\n

Note: Award (M1) for correct calculation of the number of panels on either short side with no further incorrect working.

\n

20       (A1)(ft)(G2)

\n

Note: Follow through from part (a). Do not award (M0)(M1)(A1)(ft).

\n

[3 marks]

\n
c.
\n
\n

20 × 1.6 × 0.95  (= 30.4)       (M1)

\n

Note: Award (M1) for their 20 × 1.6 × 0.95 or 30.4 seen. Follow through from their 20 in part (c). Award (M0) if their 20 is not an integer.

\n

\n\n|\n\n\n\n29\n\n30.4\n\n\n30.4\n\n\n\n|\n\n×\n100\n\n\n\n      (M1)

\n

Note: Award (M1) for correct substitution of their 30.4 into the percentage error formula. Their 30.4 must be exact.

\n

found. Accept a method in two steps where “×100” is implicit from their answer.

\n

The second (M1) is contingent on the first (M1) being awarded, eg do not award (M0)(M1)(A0).

\n

4.61 (%) (4.60526 (%))       (A1)(ft)(G3)

\n

Note: Follow through from their answer to part (c). Percentage sign is not required.

\n

Award (G2) for an unsupported final answer of 4.61.

\n

[3 marks]

\n
d.
\n
\n

1 × 9 (array)  OR  18 (total panels)       (R1)(ft)

\n

Note: Award (R1) for one correct array seen (1 × 9) or total number of panels (18). Working is not required, but award (R0) for incorrect working seen. Correct working is as follows. \n\n(\n\n\n\n10\n\n0.6\n\n\n0.95\n\n\n\n,\n\n\n\n\n\n2.84\n\n0.6\n\n\n1.6\n\n\n\n,\n\n\n\n\n\n2.745\n\n0.6\n\n\n1.6\n\n\n\n)\n\n
Reasoning may compare both sides of the roof or just one side; accept correct comparisons with part (c) values. Follow through from their treatment of tolerances in part (c) and maximum number of panels.
Award (R0) for any approach with no clearance or for any method which includes further incorrect working.

\n

No    (new arrangement will mean fewer solar panels)         (A1)(ft)

\n

Note: Follow through from their maximum number of panels in part (c). Do not award (R0)(A1)(ft).

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "19M.2.SL.TZ1.T_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Note:     In this question, distance is in metres and time is in seconds.

\n

 

\n

A particle moves along a horizontal line starting at a fixed point A. The velocity \nv\n of the particle, at time \nt\n, is given by \nv\n(\nt\n)\n=\n\n\n2\n\n\nt\n2\n\n\n\n4\nt\n\n\n\n\nt\n2\n\n\n\n2\nt\n+\n2\n\n\n, for \n0\n\nt\n\n5\n. The following diagram shows the graph of \nv\n

\n

\"M17/5/MATME/SP2/ENG/TZ2/07\"

\n

There are \nt\n-intercepts at \n(\n0\n,\n\n \n\n0\n)\n and \n(\n2\n,\n\n \n\n0\n)\n.

\n

Find the maximum distance of the particle from A during the time \n0\n\nt\n\n5\n and justify your answer.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 (displacement)

\n

recognizing \ns\n=\n\n\nv\n\nd\n\nt\n\n     (M1)

\n

consideration of displacement at \nt\n=\n2\n and \nt\n=\n5\n (seen anywhere)     M1

\n

eg\n\n\n\n\n\n\n\n\n0\n2\n\nv\n and \n\n\n0\n5\n\nv\n

\n

 

\n

Note:     Must have both for any further marks.

\n

 

\n

correct displacement at \nt\n=\n2\n and \nt\n=\n5\n (seen anywhere)     A1A1

\n

\n\n2.28318\n (accept 2.28318), 1.55513

\n

valid reasoning comparing correct displacements     R1

\n

eg\n\n\n\n\n\n\n\n|\n\n\n2.28\n\n|\n\n>\n\n|\n\n1.56\n\n|\n\n, more left than right

\n

2.28 (m)     A1     N1

\n

 

\n

Note:     Do not award the final A1 without the R1.

\n

 

\n

METHOD 2 (distance travelled)

\n

recognizing distance \n=\n\n\n\n|\nv\n|\n\n\nd\n\nt\n\n     (M1)

\n

consideration of distance travelled from \nt\n=\n0\n to 2 and \nt\n=\n2\n to 5 (seen anywhere)     M1

\n

eg\n\n\n\n\n\n\n\n\n0\n2\n\nv\n and \n\n\n2\n5\n\nv\n

\n

 

\n

Note:     Must have both for any further marks

\n

 

\n

correct distances travelled (seen anywhere)     A1A1

\n

2.28318, (accept \n\n2.28318\n), 3.83832

\n

valid reasoning comparing correct distance values     R1

\n

eg\n\n\n\n\n\n\n3.84\n\n2.28\n<\n2.28\n,\n\n \n\n3.84\n<\n2\n×\n2.28\n

\n

2.28 (m)     A1     N1

\n

 

\n

Note:     Do not award the final A1 without the R1.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.SL.TZ2.S_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

The following table shows the probability distribution of a discrete random variable \nA\n, in terms of an angle \nθ\n.

\n

\"M17/5/MATME/SP1/ENG/TZ1/10\"

\n
\n

Show that cos θ = 3 4 .

\n
[6]
\n
a.
\n
\n

Given that tan θ > 0 , find tan θ .

\n
[3]
\n
b.
\n
\n

Let y = 1 cos x , for 0 < x < π 2 . The graph of y between x = θ and  x = π 4 is rotated 360° about the x -axis. Find the volume of the solid formed.

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of summing to 1     (M1)

\n

eg p = 1

\n

correct equation     A1

\n

eg cos θ + 2 cos 2 θ = 1

\n

correct equation in cos θ     A1

\n

eg cos θ + 2 ( 2 cos 2 θ 1 ) = 1 ,   4 cos 2 θ + cos θ 3 = 0

\n

evidence of valid approach to solve quadratic     (M1)

\n

eg factorizing equation set equal to 0 ,   1 ± 1 4 × 4 × ( 3 ) 8

\n

correct working, clearly leading to required answer     A1

\n

eg ( 4 cos θ 3 ) ( cos θ + 1 ) ,   1 ± 7 8

\n

correct reason for rejecting cos θ 1     R1

\n

eg cos θ is a probability (value must lie between 0 and 1), cos θ > 0

\n

 

\n

Note:     Award R0 for cos θ 1 without a reason.

\n

 

\n

cos θ = 3 4    AG  N0

\n
a.
\n
\n

valid approach     (M1)

\n

eg sketch of right triangle with sides 3 and 4, sin 2 x + cos 2 x = 1

\n

correct working     

\n

(A1)

\n

eg missing side = 7 ,   7 4 3 4

\n

tan θ = 7 3     A1     N2

\n

[3 marks]

\n
b.
\n
\n

attempt to substitute either limits or the function into formula involving f 2     (M1)

\n

eg π θ π 4 f 2 ,   ( 1 cos x ) 2

\n

correct substitution of both limits and function     (A1)

\n

eg π θ π 4 ( 1 cos x ) 2 d x

\n

correct integration     (A1)

\n

eg tan x

\n

substituting their limits into their integrated function and subtracting     (M1)

\n

eg tan π 4 tan θ

\n

 

\n

Note:     Award M0 if they substitute into original or differentiated function.

\n

 

\n

tan π 4 = 1     (A1)

\n

eg 1 tan θ

\n

V = π π 7 3     A1     N3

\n

 

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ1.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

The faces of a fair six-sided die are numbered 1, 2, 2, 4, 4, 6. Let \nX\n be the discrete random variable that models the score obtained when this die is rolled.

\n
\n

Complete the probability distribution table for \nX\n.

\n

\"N16/5/MATHL/HP1/ENG/TZ0/02.a\"

\n
[2]
\n
a.
\n
\n

Find the expected value of \nX\n.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"N16/5/MATHL/HP1/ENG/TZ0/02.a/M\"     A1A1

\n

 

\n

Note:     Award A1 for each correct row.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n\nE\n\n(\nX\n)\n=\n1\n×\n\n1\n6\n\n+\n2\n×\n\n1\n3\n\n+\n4\n×\n\n1\n3\n\n+\n6\n×\n\n1\n6\n\n    (M1)

\n

\n=\n\n\n19\n\n6\n\n\n \n\n\n(\n\n=\n3\n\n1\n6\n\n\n)\n\n    A1

\n

 

\n

Note:     If the probabilities in (a) are not values between 0 and 1 or lead to \n\nE\n\n(\nX\n)\n>\n6\n award M1A0 to correct method using the incorrect probabilities; otherwise allow FT marks.

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.AHL.TZ0.H_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\nx\n\n\n\ne\n\n\n\nx\n\n\n\n and \ng\n(\nx\n)\n=\n\n3\nf\n(\nx\n)\n+\n1\n.

\n

The graphs of \nf\n and \ng\n intersect at \nx\n=\np\n and \nx\n=\nq\n, where \np\n<\nq\n.

\n
\n

Find the value of \np\n and of \nq\n.

\n
[3]
\n
a.
\n
\n

Hence, find the area of the region enclosed by the graphs of \nf\n and \ng\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid attempt to find the intersection     (M1)

\n

eg\n\n\n\n\n\n\nf\n=\ng\n, sketch, one correct answer

\n

\np\n=\n0.357402\n,\n\n \n\nq\n=\n2.15329\n

\n

\np\n=\n0.357\n,\n\n \n\nq\n=\n2.15\n     A1A1     N3

\n

[3 marks]

\n
a.
\n
\n

attempt to set up an integral involving subtraction (in any order)     (M1)

\n

eg\n\n\n\n\n\n\n\n\np\nq\n\n\n\n[\n\nf\n(\nx\n)\n\ng\n(\nx\n)\n\n]\n\n\nd\n\nx\n,\n\n \n\n\n\n\np\nq\n\n\nf\n(\nx\n)\n\nd\n\nx\n\n\n\n\np\nq\n\n\ng\n(\nx\n)\n\nd\n\nx\n\n

\n

0.537667

\n

\n\narea\n\n=\n0.538\n     A2     N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.2.SL.TZ0.S_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A random variable \nX\n has a probability distribution given in the following table.

\n

\"N16/5/MATHL/HP2/ENG/TZ0/01\"

\n
\n

Determine the value of \n\nE\n\n(\n\n\nX\n2\n\n\n)\n.

\n
[2]
\n
a.
\n
\n

Find the value of \n\nVar\n\n(\nX\n)\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nE\n\n(\n\n\nX\n2\n\n\n)\n=\nΣ\n\n\nx\n2\n\n\n\n\nP\n\n(\nX\n=\nx\n)\n=\n10.37\n\n \n\n(\n=\n10.4\n\n 3 sf)\n\n    (M1)A1

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

\n\nsd\n\n(\nX\n)\n=\n1.44069\n\n    (M1)(A1)

\n

\n\nVar\n\n(\nX\n)\n=\n2.08\n\n \n\n(\n=\n2.0756\n)\n    A1

\n

METHOD 2

\n

\n\nE\n\n(\nX\n)\n=\n2.88\n\n \n\n(\n=\n0.06\n+\n0.27\n+\n0.5\n+\n0.98\n+\n0.63\n+\n0.44\n)\n    (A1)

\n

use of \n\nVar\n\n(\nX\n)\n=\n\nE\n\n(\n\n\nX\n2\n\n\n)\n\n\n\n\n(\n\n\nE\n\n(\nX\n)\n\n)\n\n2\n\n\n     (M1)

\n

 

\n

Note: Award (M1) only if \n\n\n\n(\n\n\nE\n\n(\nX\n)\n\n)\n\n2\n\n\n is used correctly.

\n

 

\n

\n\n(\n\n\nVar\n\n(\nX\n)\n=\n10.37\n\n8.29\n\n)\n\n

\n

\n\nVar\n\n(\nX\n)\n=\n2.08\n\n \n\n(\n=\n2.0756\n)\n    A1

\n

 

\n

Note: Accept 2.11.

\n

 

\n

METHOD 3

\n

\n\nE\n\n(\nX\n)\n=\n2.88\n\n \n\n(\n=\n0.06\n+\n0.27\n+\n0.5\n+\n0.98\n+\n0.63\n+\n0.44\n)\n    (A1)

\n

use of \n\nVar\n\n(\nX\n)\n=\n\nE\n\n\n(\n\n\n\n\n\n(\n\nX\n\n\nE\n\n(\nX\n)\n\n)\n\n\n2\n\n\n\n)\n\n     (M1)

\n

\n(\n0.679728\n+\n\n+\n0.549152\n)\n

\n

\n\nVar\n\n(\nE\n)\n=\n2.08\n\n \n\n(\n=\n2.0756\n)\n    A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.2.AHL.TZ0.H_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

The width of a rectangular garden is 4.5 metres shorter than its length, which is \nx\n metres.

\n
\n

The perimeter of the garden is 111 m.

\n
\n

Write down an expression for the width of the garden in terms of x .

\n
[1]
\n
a.
\n
\n

Write down an equation for the perimeter of the garden in terms of x .

\n
[1]
\n
b.
\n
\n

Find the value of x .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

x 4.5      (A1) (C1)

\n

Note: Accept w = x 4.5   OR  width = x 4.5 .

\n

[1 mark]

\n
a.
\n
\n

2 x + 2 ( x 4.5 ) = 111      (A1)(ft) (C1)

\n

Note: Follow through from their expression for the width from part (a).

\n

[1 mark]

\n
b.
\n
\n

4 x 9 = 111  (or equivalent)     (M1)

\n

Note: Award (M1) for correctly removing the parentheses and collecting x terms. This may be seen in part (b).

\n

( x = ) 30      (A1)(ft) (C2)

\n

Note: Follow through from their equation from part (b) provided x > 4.5 .

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_7", "topics": [], "subtopics": [] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n6\n\nln\n\n(\n\n\nx\n2\n\n\n+\n2\n)\n, for \nx\n\n\nR\n\n. The graph of \nf\n passes through the point \n(\np\n,\n\n \n\n4\n)\n, where \np\n>\n0\n.

\n
\n

Find the value of p .

\n
[2]
\n
a.
\n
\n

The following diagram shows part of the graph of f .

\n

\"N17/5/MATME/SP2/ENG/TZ0/05.b\"

\n

The region enclosed by the graph of f , the x -axis and the lines x = p and x = p is rotated 360° about the x -axis. Find the volume of the solid formed.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

valid approach     (M1)

\n

eg f ( p ) = 4 , intersection with y = 4 ,   ± 2.32

\n

2.32143

\n

p = e 2 2 (exact), 2.32     A1     N2

\n

[2 marks]

\n
a.
\n
\n

attempt to substitute either their limits or the function into volume formula (must involve f 2 , accept reversed limits and absence of π and/or d x , but do not accept any other errors)     (M1)

\n

eg 2.32 2.32 f 2 ,   π ( 6 ln ( x 2 + 2 ) ) 2 d x ,  105.675

\n

331.989

\n

volume = 332     A2     N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.2.SL.TZ0.S_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Let \ny\n=\n\n\n\n(\n\n\n\nx\n3\n\n\n+\nx\n\n)\n\n\n\n3\n2\n\n\n\n\n.

\n
\n

Consider the functions \nf\n\n(\nx\n)\n\n=\n\n\n\nx\n3\n\n\n+\nx\n\n and \ng\n\n(\nx\n)\n\n=\n6\n\n3\n\n\nx\n2\n\n\n\n\n\nx\n3\n\n\n+\nx\n\n, for \nx\n ≥ 0.

\n

The graphs of \nf\n and \ng\n are shown in the following diagram.

\n

\n

The shaded region \nR\n is enclosed by the graphs of \nf\n, \ng\n, the \ny\n-axis and \nx\n=\n1\n.

\n
\n

Hence find \n\n\n\n(\n\n3\n\n\nx\n2\n\n\n+\n1\n\n)\n\n\n\n\nx\n3\n\n\n+\nx\n\n\n\n\nd\n\nx\n.

\n
[3]
\n
b.
\n
\n

Write down an expression for the area of \nR\n.

\n
[2]
\n
c.
\n
\n

Hence find the exact area of \nR\n.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

integrating by inspection from (a) or by substitution       (M1)

\n

eg   \n\n2\n3\n\n\n\n\n3\n2\n\n\n\n(\n\n3\n\n\nx\n2\n\n\n+\n1\n\n)\n\n\n\n\nx\n3\n\n\n+\nx\n\n\n\nd\n\nx\n\nu\n=\n\n\nx\n3\n\n\n+\nx\n\n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n3\n\n\nx\n2\n\n\n+\n1\n, \n\n\n\n\nu\n\n\n1\n2\n\n\n\n\n\n\n\n\n\n\nu\n\n\n3\n2\n\n\n\n\n\n\n1.5\n\n\n

\n

correct integrated expression in terms of \nx\n       A2 N3

\n

eg   \n\n2\n3\n\n\n\n\n(\n\n\n\nx\n3\n\n\n+\nx\n\n)\n\n\n\n3\n2\n\n\n\n\n+\nC\n,  \n\n\n\n\n\n\n(\n\n\n\nx\n3\n\n\n+\nx\n\n)\n\n\n\n1.5\n\n\n\n\n\n1.5\n\n\n+\nC\n

\n

[3 marks]

\n

 

\n

 

\n
b.
\n
\n

integrating and subtracting functions (in any order)        (M1)

\n

eg   \n\n\ng\n\nf\n\n,  \n\n\nf\n\n\ng\n\n

\n

correct integral (including limits, accept absence of \n\n\nd\n\nx\n\n)       A1 N2

\n

eg   \n\n\n0\n1\n\n\n\n(\n\ng\n\nf\n\n)\n\n\n\n\nd\n\nx\n,  \n\n\n0\n1\n\n\n6\n\n3\n\n\nx\n2\n\n\n\n\n\nx\n3\n\n\n+\nx\n\n\n\n\n\nx\n3\n\n\n+\nx\n\n\n\n\nd\n\nx\n,  \n\n\n0\n1\n\n\ng\n\n(\nx\n)\n\n\n\n\n\n0\n1\n\n\nf\n\n(\nx\n)\n\n\n

\n

[2 marks]

\n
c.
\n
\n

recognizing \n\n\n\nx\n3\n\n\n+\nx\n\n is a common factor (seen anywhere, may be seen in part (c))       (M1)

\n

eg   \n\n(\n\n\n3\n\n\nx\n2\n\n\n\n1\n\n)\n\n\n\n\nx\n3\n\n\n+\nx\n\n\n\n\n6\n\n\n(\n\n3\n\n\nx\n2\n\n\n+\n1\n\n)\n\n\n\n\n\nx\n3\n\n\n+\nx\n\n,   \n\n(\n\n3\n\n\nx\n2\n\n\n\n1\n\n)\n\n\n\n\nx\n3\n\n\n+\nx\n\n

\n

correct integration      (A1)(A1)

\n

eg   \n6\nx\n\n\n2\n3\n\n\n\n\n(\n\n\n\nx\n3\n\n\n+\nx\n\n)\n\n\n\n3\n2\n\n\n\n\n

\n

Note: Award A1 for \n6\nx\n and award A1 for \n\n\n2\n3\n\n\n\n\n(\n\n\n\nx\n3\n\n\n+\nx\n\n)\n\n\n\n3\n2\n\n\n\n\n.

\n

substituting limits into their integrated function and subtracting (in any order)       (M1)

\n

eg   \n6\n\n\n2\n3\n\n\n\n\n(\n\n\n\n1\n3\n\n\n+\n1\n\n)\n\n\n\n3\n2\n\n\n\n\n,  \n0\n\n\n[\n\n6\n\n\n2\n3\n\n\n\n\n\n(\n\n\n\n1\n3\n\n\n+\n1\n\n)\n\n\n\n\n3\n2\n\n\n\n\n\n]\n\n

\n

correct working       (A1)

\n

eg   \n6\n\n\n2\n3\n\n×\n2\n\n2\n\n,  \n6\n\n\n2\n3\n\n×\n\n4\n\n×\n\n2\n\n

\n

area of \nR\n=\n6\n\n\n\n4\n\n2\n\n\n3\n\n\n\n\n\n(\n\n=\n6\n\n\n2\n3\n\n\n8\n\n\n,\n\n\n\n\n6\n\n\n2\n3\n\n×\n\n\n2\n\n\n3\n2\n\n\n\n\n\n,\n\n\n\n\n\n\n18\n\n4\n\n2\n\n\n3\n\n\n)\n\n       A1  N3

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.1.SL.TZ2.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

The number of bananas that Lucca eats during any particular day follows a Poisson distribution with mean 0.2.

\n
\n

Find the probability that Lucca eats at least one banana in a particular day.

\n
[2]
\n
a.
\n
\n

Find the expected number of weeks in the year in which Lucca eats no bananas.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

let X be the number of bananas eaten in one day

\n

X Po ( 0.2 )

\n

P ( X 1 ) = 1 P ( X = 0 )     (M1)

\n

= 0.181   ( = 1 e 0.2 )     A1

\n

[2 marks]

\n
a.
\n
\n

EITHER

\n

let Y be the number of bananas eaten in one week

\n

Y Po ( 1.4 )     (A1)

\n

P ( Y = 0 ) = 0.246596   ( = e 1.4 )     (A1)

\n

OR

\n

let Z be the number of days in one week at least one banana is eaten

\n

Z B ( 7 ,   0.181 )     (A1)

\n

P ( Z = 0 ) = 0.246596     (A1)

\n

THEN

\n

52 × 0.246596     (M1)

\n

= 12.8   ( = 52 e 1.4 )     A1

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.2.AHL.TZ0.H_6", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-13-rational-functions" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n1\n\n\n2\nx\n\n1\n\n\n\n, for \nx\n>\n\n1\n2\n\n.

\n
\n

Find \n\n\n\n\n\n\n(\n\nf\n\n(\nx\n)\n\n\n)\n\n\n2\n\n\n\nd\n\nx\n\n.

\n
[3]
\n
a.
\n
\n

Part of the graph of f is shown in the following diagram.

\n

\n

The shaded region R is enclosed by the graph of f, the x-axis, and the lines x = 1 and x = 9 . Find the volume of the solid formed when R is revolved 360° about the x-axis.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct working      (A1)

\n

eg   \n\n\n\n1\n\n2\nx\n\n1\n\n\n\nd\n\nx\n,\n\n\n\n\n\n\n\n\n(\n\n2\nx\n\n1\n\n)\n\n\n\n\n1\n\n\n\n,\n\n\n\n1\n\n2\nx\n\n1\n\n\n,\n\n\n\n\n\n\n\n\n(\n\n\n1\n\n\nu\n\n\n\n\n)\n\n\n2\n\n\n\n\n\nd\n\nu\n\n2\n\n\n\n\n

\n

\n\n\n\n\n\n(\n\nf\n\n(\nx\n)\n\n\n)\n\n\n2\n\n\n\nd\n\nx\n=\n\n1\n2\n\n\nln\n\n\n(\n\n2\nx\n\n1\n\n)\n\n+\nc\n      A2 N3

\n

Note: Award A1 for \n\n1\n2\n\n\nln\n\n\n(\n\n2\nx\n\n1\n\n)\n\n.

\n

[3 marks]

\n
a.
\n
\n

attempt to substitute either limits or the function into formula involving f 2 (accept absence of \nπ\n / dx)     (M1)

\n

eg   \n\n\n1\n9\n\n\n\n\ny\n2\n\n\n\nd\n\nx\n,\n\n\n\nπ\n\n\n\n\n\n(\n\n\n1\n\n\n2\nx\n\n1\n\n\n\n\n)\n\n\n2\n\n\n\nd\n\nx\n,\n\n\n\n\n[\n\n\n1\n2\n\n\nln\n\n\n(\n\n2\nx\n\n1\n\n)\n\n\n]\n\n1\n9\n\n

\n

substituting limits into their integral and subtracting (in any order)     (M1)

\n

eg  \n\nπ\n2\n\n\n(\n\n\nln\n\n\n(\n\n17\n\n)\n\n\n\nln\n\n\n(\n1\n)\n\n\n)\n\n,\n\n\nπ\n\n(\n\n0\n\n\n1\n2\n\n\nln\n\n\n(\n\n2\n×\n9\n\n1\n\n)\n\n\n)\n\n

\n

correct working involving calculating a log value or using log law     (A1)

\n

eg  \n\nln\n\n\n(\n1\n)\n\n=\n0\n,\n\n\n\nln\n\n\n(\n\n\n\n17\n\n1\n\n\n)\n\n

\n

\n\nπ\n2\n\n\nln\n\n17\n\n\n\n\n\n(\n\n\naccept \n\nπ\n\nln\n\n\n17\n\n\n)\n\n    A1 N3

\n

Note: Full FT may be awarded as normal, from their incorrect answer in part (a), however, do not award the final two A marks unless they involve logarithms.

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ1.S_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A particle P moves along a straight line. Its velocity \n\n\nv\n\nP\n\n\n\n\n m\n\n\n\n\n\ns\n\n\n\n1\n\n\n\n after \nt\n seconds is given by \n\n\nv\n\nP\n\n\n\n=\n\nt\n\nsin\n\n\n(\n\n\nπ\n2\n\nt\n\n)\n\n, for \n0\n\nt\n\n8\n. The following diagram shows the graph of \n\n\nv\n\nP\n\n\n\n.

\n

\"M17/5/MATME/SP2/ENG/TZ1/07\"

\n
\n

Write down the first value of \nt\n at which P changes direction.

\n
[1]
\n
a.i.
\n
\n

Find the total distance travelled by P, for \n0\n\nt\n\n8\n.

\n
[2]
\n
a.ii.
\n
\n

A second particle Q also moves along a straight line. Its velocity, \n\n\nv\n\nQ\n\n\n\n\n m\n\n\n\n\n\ns\n\n\n\n1\n\n\n\n after \nt\n seconds is given by \n\n\nv\n\nQ\n\n\n\n=\n\nt\n\n for \n0\n\nt\n\n8\n. After \nk\n seconds Q has travelled the same total distance as P.

\n

Find \nk\n.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

\nt\n=\n2\n     A1     N1

\n

[1 mark]

\n
a.i.
\n
\n

substitution of limits or function into formula or correct sum     (A1)

\n

eg\n\n\n\n\n\n\n\n\n0\n8\n\n\n\n|\nv\n|\n\n\nd\n\nt\n,\n\n \n\n\n\n\n|\n\n\n\nv\nQ\n\n\n\n|\n\n\nd\n\nt\n,\n\n \n\n\n\n0\n2\n\n\nv\n\nd\n\nt\n\n\n\n2\n4\n\n\nv\n\nd\n\nt\n+\n\n\n4\n6\n\n\nv\n\nd\n\nt\n\n\n\n6\n8\n\n\nv\n\nd\n\nt\n\n\n\n\n\n\n

\n

9.64782

\n

distance \n=\n9.65\n\n (metres)\n\n     A1     N2

\n

[2 marks]

\n
a.ii.
\n
\n

correct approach     (A1)

\n

eg\n\n\n\n\n\n\ns\n=\n\n\n\nt\n\n,\n\n \n\n\n\n0\nk\n\n\n\nt\n\n\n\n\nd\n\nt\n,\n\n \n\n\n\n0\nk\n\n\n\n|\n\n\n\nv\n\nQ\n\n\n\n\n|\n\n\nd\n\nt\n\n

\n

correct integration     (A1)

\n

eg\n\n\n\n\n\n\n\n\n\nt\n\n=\n\n2\n3\n\n\n\nt\n\n\n3\n2\n\n\n\n\n+\nc\n,\n\n \n\n\n\n[\n\n\n2\n3\n\n\n\nx\n\n\n3\n2\n\n\n\n\n\n]\n\n0\nk\n\n,\n\n \n\n\n2\n3\n\n\n\nk\n\n\n3\n2\n\n\n\n\n\n

\n

equating their expression to the distance travelled by their P     (M1)

\n

eg\n\n\n\n\n\n\n\n2\n3\n\n\n\nk\n\n\n3\n2\n\n\n\n\n=\n9.65\n,\n\n \n\n\n\n0\nk\n\n\n\nt\n\n\nd\n\nt\n=\n9.65\n\n

\n

5.93855

\n

5.94 (seconds)     A1     N3

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.SL.TZ1.S_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

The volume of a hemisphere, V, is given by the formula

\n

V\n\n\n\n4\n\n\n\nS\n3\n\n\n\n\n243\n\nπ\n\n\n\n,

\n

where S is the total surface area.

\n

The total surface area of a given hemisphere is 350 cm2.

\n
\n

Calculate the volume of this hemisphere in cm3.

\n

Give your answer correct to one decimal place.

\n
[3]
\n
a.
\n
\n

Write down your answer to part (a) correct to the nearest integer.

\n
[1]
\n
b.
\n
\n

Write down your answer to part (b) in the form a × 10k , where 1 ≤ a < 10 and k \n\nZ\n\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\n4\n\n\n\n\n\n(\n\n350\n\n)\n\n\n3\n\n\n\n\n243\n\nπ\n\n\n\n  OR \n\n\n\n171500\n\n000\n\n\n763.407\n\n\n\n\n\n     (M1)

\n

Note: Award (M1) for substitution of 350 into volume formula.

\n

 

\n

= 473.973…    (A1) 

\n

= 474 (cm3)    (A1)(ft)   (C3)

\n

 

\n

Note: The final (A1)(ft) is awarded for rounding their answer to 1 decimal place provided the unrounded answer is seen.

\n

 

\n

[3 marks]

\n
a.
\n
\n

474 (cm3)      (A1)(ft) (C1)

\n

Note: Follow through from part (a).

\n

 

\n

[1 mark]

\n
b.
\n
\n

4.74 × 102 (cm3)     (A1)(ft)(A1)(ft)   (C2)

\n

 

\n

Note: Follow through from part (b) only.

\n

Award (A0)(A0) for answers of the type 0.474 × 103.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.1.SL.TZ0.T_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Timmy owns a shop. His daily income from selling his goods can be modelled as a normal distribution, with a mean daily income of $820, and a standard deviation of $230. To make a profit, Timmy’s daily income needs to be greater than $1000.

\n
\n

Calculate the probability that, on a randomly selected day, Timmy makes a profit.

\n
[2]
\n
a.
\n
\n

The shop is open for 24 days every month.

\n

Calculate the probability that, in a randomly selected month, Timmy makes a profit on between 5 and 10 days (inclusive).

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

X ~ N(820, 2302)       (M1)

\n

Note: Award M1 for an attempt to use normal distribution. Accept labelled normal graph.

\n

⇒P(X > 1000) = 0.217       A1

\n

[2 marks]

\n
a.
\n
\n

Y ~ B(24,0.217...)       (M1)

\n

Note: Award M1 for recognition of binomial distribution with parameters.

\n

P(Y ≤ 10) − P(Y ≤ 4)         (M1)

\n

Note: Award M1 for an attempt to find P(5 ≤ Y ≤ 10) or P(Y ≤ 10) − P(Y ≤ 4).

\n

= 0.613       A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.AHL.TZ2.H_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n4\n\n2\n\n\n\ne\n\nx\n\n\n. The following diagram shows part of the graph of \nf\n.

\n

\n
\n

Find the \nx\n-intercept of the graph of \nf\n.

\n
[2]
\n
a.
\n
\n

The region enclosed by the graph of \nf\n, the \nx\n-axis and the \ny\n-axis is rotated 360º about the \nx\n-axis. Find the volume of the solid formed.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach          (M1)

\n

eg   \nf\n\n(\nx\n)\n\n=\n0\n,   \n4\n\n2\n\n\n\ne\n\nx\n\n\n=\n0\n

\n

0.693147

\n

\nx\n = ln 2 (exact), 0.693      A1 N2

\n

[2 marks]

\n
a.
\n
\n

attempt to substitute either their correct limits or the function into formula         (M1)

\n

involving \n\n\nf\n2\n\n\n

\n

eg   \n\n\n0\n\n0.693\n\n\n\n\n\nf\n2\n\n\n\n ,   \nπ\n\n\n\n\n\n(\n\n4\n\n2\n\n\n\ne\n\nx\n\n\n\n)\n\n\n2\n\n\n\nd\n\nx\n,   \n\n\n0\n\n\nln\n\n\n2\n\n\n\n\n\n\n\n(\n\n4\n\n2\n\n\n\ne\n\nx\n\n\n\n)\n\n\n2\n\n\n\n

\n

3.42545

\n

volume = 3.43     A2 N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.SL.TZ2.S_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

In this question distance is in centimetres and time is in seconds.

\n

Particle A is moving along a straight line such that its displacement from a point P, after \nt\n seconds, is given by \n\n\ns\n\nA\n\n\n\n=\n15\n\nt\n\n6\n\n\nt\n3\n\n\n\n\n\ne\n\n\n\n0.8\nt\n\n\n\n, 0 ≤ \nt\n ≤ 25. This is shown in the following diagram.

\n

\n
\n

Another particle, B, moves along the same line, starting at the same time as particle A. The velocity of particle B is given by \n\n\nv\n\nB\n\n\n\n=\n8\n\n2\nt\n, 0 ≤ \nt\n ≤ 25.

\n
\n

Find the initial displacement of particle A from point P.

\n
[2]
\n
a.
\n
\n

Find the value of \nt\n when particle A first reaches point P.

\n
[2]
\n
b.
\n
\n

Find the value of \nt\n when particle A first changes direction.

\n
[2]
\n
c.
\n
\n

Find the total distance travelled by particle A in the first 3 seconds.

\n
[3]
\n
d.
\n
\n

Given that particles A and B start at the same point, find the displacement function \n\n\ns\n\nB\n\n\n\n for particle B.

\n
[5]
\n
e.i.
\n
\n

Find the other value of \nt\n when particles A and B meet.

\n
[2]
\n
e.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach       (M1)

\n

eg   \n\n\ns\n\nA\n\n\n\n\n(\n0\n)\n\n\n,\n\n\n\ns\n\n(\n0\n)\n\n\n,\n\n\n\nt\n=\n0\n

\n

15 (cm)      A1  N2

\n

[2 marks]

\n
a.
\n
\n

valid approach       (M1)

\n

eg  \n\n\ns\n\nA\n\n\n\n=\n0\n\n,\n\n\n\ns\n=\n0\n\n,\n\n\n\n6.79321\n\n,\n\n\n\n14.8651\n

\n

2.46941

\n

\nt\n = 2.47  (seconds)      A1  N2

\n

[2 marks]

\n
b.
\n
\n

recognizing when change in direction occurs      (M1)

\n

eg  slope of \ns\n changes sign, \n\ns\n\n\n=\n0\n, minimum point, 10.0144, (4.08, −4.66)

\n

4.07702

\n

\nt\n = 4.08  (seconds)      A1  N2

\n

[2 marks]

\n
c.
\n
\n

METHOD 1 (using displacement)

\n

correct displacement or distance from P at \nt\n=\n3\n (seen anywhere)        (A1)

\n

eg   −2.69630,  2.69630

\n

valid approach    (M1)

\n

eg   15 + 2.69630,  \ns\n\n(\n3\n)\n\n\ns\n\n(\n0\n)\n\n,  −17.6963

\n

17.6963

\n

17.7  (cm)      A1  N2

\n

 

\n

METHOD 2 (using velocity)

\n

attempt to substitute either limits or the velocity function into distance formula involving \n\n|\nv\n|\n\n       (M1)

\n

eg  \n\n\n0\n3\n\n\n\n|\nv\n|\n\n\nd\n\nt\n\n ,   \n\n\n\n|\n\n\n1\n\n18\n\n\nt\n2\n\n\n\n\n\ne\n\n\n\n0.8\nt\n\n\n\n+\n4.8\n\n\nt\n3\n\n\n\n\n\ne\n\n\n\n0.8\nt\n\n\n\n\n|\n\n\n

\n

17.6963

\n

17.7  (cm)      A1  N2

\n

[3 marks]

\n
d.
\n
\n

recognize the need to integrate velocity       (M1)

\n

eg   \n\n\nv\n\n(\nt\n)\n\n\n

\n

\n8\nt\n\n\n\n2\n\n\nt\n2\n\n\n\n2\n\n+\nc\n  (accept \nx\n instead of \nt\n and missing \nc\n)         (A2)

\n

substituting initial condition into their integrated expression (must have \nc\n)        (M1)

\n

eg   \n15\n=\n8\n\n(\n0\n)\n\n\n\n\n2\n\n\n\n\n(\n0\n)\n\n\n2\n\n\n\n2\n\n+\nc\n,   \nc\n=\n15\n

\n

\n\n\ns\n\nB\n\n\n\n\n(\nt\n)\n\n=\n8\nt\n\n\n\nt\n2\n\n\n+\n15\n       A1  N3

\n

[5 marks]

\n
e.i.
\n
\n

valid approach      (M1)

\n

eg   \n\n\ns\n\nA\n\n\n\n=\n\n\ns\n\nB\n\n\n\n, sketch, (9.30404, 2.86710)

\n

9.30404

\n

\nt\n=\n9.30\n (seconds)     A1  N2

\n

Note: If candidates obtain \n\n\ns\n\nB\n\n\n\n\n(\nt\n)\n\n=\n8\nt\n\n\n\nt\n2\n\n\n in part (e)(i), there are 2 solutions for part (e)(ii), 1.32463 and 7.79009. Award the last A1 in part (e)(ii) only if both solutions are given.

\n

[2 marks]

\n
e.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
", "question_id": "19M.2.SL.TZ2.S_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

All lengths in this question are in metres.

\n

 

\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n\n\n4\n\n\n\nx\n2\n\n\n\n8\n\n\n, for −2 ≤ \nx\n ≤ 2. In the following diagram, the shaded region is enclosed by the graph of \nf\n and the \nx\n-axis.

\n

\n

A container can be modelled by rotating this region by 360˚ about the \nx\n-axis.

\n
\n

Water can flow in and out of the container.

\n

The volume of water in the container is given by the function \ng\n\n(\nt\n)\n\n, for 0 ≤ \nt\n ≤ 4 , where \nt\n is measured in hours and \ng\n\n(\nt\n)\n\n is measured in m3. The rate of change of the volume of water in the container is given by \n\ng\n\n\n\n(\nt\n)\n\n=\n0.9\n\n2.5\n\n\ncos\n\n\n(\n\n0.4\n\n\nt\n2\n\n\n\n)\n\n.

\n
\n

The volume of water in the container is increasing only when \np\n < \nt\n < \nq\n.

\n
\n

Find the volume of the container.

\n
[3]
\n
a.
\n
\n

Find the value of  p and of  q .

\n
[3]
\n
b.i.
\n
\n

During the interval  p  < t  < q , he volume of water in the container increases by k  m3. Find the value of k .

\n
[3]
\n
b.ii.
\n
\n

When t = 0, the volume of water in the container is 2.3 m3. It is known that the container is never completely full of water during the 4 hour period.

\n

 

\n

Find the minimum volume of empty space in the container during the 4 hour period.

\n
[5]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to substitute correct limits or the function into formula involving  f 2       (M1)

\n

eg       π 2 2 y 2 d y ,   π ( 4 x 2 8 ) 2 d x

\n

4.18879

\n

volume = 4.19,  4 3 π   (exact) (m3)      A2 N3

\n

Note: If candidates have their GDC incorrectly set in degrees, award M marks where appropriate, but no A marks may be awarded. Answers from degrees are p = 13.1243 and q = 26.9768 in (b)(i) and 12.3130 or 28.3505 in (b)(ii).

\n

 

\n

[3 marks]

\n

 

\n

 

\n
a.
\n
\n

recognizing the volume increases when g is positive      (M1)

\n

eg    g ( t ) > 0,  sketch of graph of g indicating correct interval

\n

1.73387, 3.56393

\n

p = 1.73,  p = 3.56      A1A1 N3

\n

 

\n

[3 marks]

\n

 

\n

 

\n
b.i.
\n
\n

valid approach to find change in volume      (M1)

\n

eg    g ( q ) g ( p ) ,   p q g ( t ) d t

\n

3.74541

\n

total amount = 3.75  (m3)      A2 N3

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

Note: There may be slight differences in the final answer, depending on which values candidates carry through from previous parts. Accept answers that are consistent with correct working.

\n

 

\n

recognizing when the volume of water is a maximum     (M1)

\n

eg   maximum when  t = q ,   0 q g ( t ) d t

\n

valid approach to find maximum volume of water      (M1)

\n

eg    2.3 + 0 q g ( t ) d t ,   2.3 + 0 p g ( t ) d t + 3.74541 ,  3.85745

\n

correct expression for the difference between volume of container and maximum value      (A1)

\n

eg    4.18879 ( 2.3 + 0 q g ( t ) d t ) ,  4.19 − 3.85745

\n

0.331334

\n

0.331 (m3)      A2 N3

\n

 

\n

[5 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.2.SL.TZ0.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-17-areas-under-curve-onto-y-axis-volume-of-revolution-(about-x-and-y-axes)" ] }, { "Question": "
\n

The random variable X has a binomial distribution with parameters n and p.
It is given that E(X) = 3.5.

\n
\n

Find the least possible value of n.

\n
[2]
\n
a.
\n
\n

It is further given that P(X ≤ 1) = 0.09478 correct to 4 significant figures.

\n

Determine the value of n and the value of p.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

np = 3.5      (A1)

\n

p ≤ 1 ⇒ least n = 4       A1

\n

[2 marks]

\n
a.
\n
\n

(1 − p)n + np(1 − p)n−1 = 0.09478     M1A1

\n

attempt to solve above equation with np = 3.5     (M1)

\n

n = 12,  p\n\n7\n\n24\n\n\n (=0.292)     A1A1

\n

Note: Do not accept n as a decimal.

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.AHL.TZ2.H_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

The marks obtained by nine Mathematical Studies SL students in their projects (x) and their final IB examination scores (y) were recorded. These data were used to determine whether the project mark is a good predictor of the examination score. The results are shown in the table.

\n

\n
\n

The equation of the regression line y on x is y = mx + c.

\n
\n

A tenth student, Jerome, obtained a project mark of 17.

\n
\n

Use your graphic display calculator to write down \n\n\n\nx\n¯\n\n\n\n, the mean project mark.

\n
[1]
\n
a.i.
\n
\n

Use your graphic display calculator to write down \n\n\n\ny\n¯\n\n\n\n, the mean examination score.

\n
[1]
\n
a.ii.
\n
\n

Use your graphic display calculator to write down r , Pearson’s product–moment correlation coefficient.

\n
[2]
\n
a.iii.
\n
\n

Find the exact value of m and of c for these data.

\n
[2]
\n
b.i.
\n
\n

Show that the point M (\n\n\n\nx\n¯\n\n\n\n, \n\n\n\ny\n¯\n\n\n\n) lies on the regression line y on x.

\n
[2]
\n
b.ii.
\n
\n

Use the regression line y on x to estimate Jerome’s examination score.

\n
[2]
\n
c.i.
\n
\n

Justify whether it is valid to use the regression line y on x to estimate Jerome’s examination score.

\n
[2]
\n
c.ii.
\n
\n

In his final IB examination Jerome scored 65.

\n

Calculate the percentage error in Jerome’s estimated examination score.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

14      (G1)

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

54     (G1)

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

0.5     (G2)

\n

 

\n

[2 marks]

\n
a.iii.
\n
\n

m = 0.875, c = 41.75  \n\n(\n\nm\n=\n\n7\n8\n\n\n,\n\n\n\nc\n=\n\n\n167\n\n4\n\n\n)\n\n        (A1)(A1)

\n

Note: Award (A1) for 0.875 seen. Award (A1) for 41.75 seen. If 41.75 is rounded to 41.8 do not award (A1).

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

y = 0.875(14) + 41.75      (M1)

\n

Note: Award (M1) for their correct substitution into their regression line. Follow through from parts (a)(i) and (b)(i).

\n

 

\n

= 54

\n

and so the mean point lies on the regression line      (A1)

\n

(accept 54 is \n\n\n\ny\n¯\n\n\n\n, the mean value of the y data)

\n

Note: Do not award (A1) unless the conclusion is explicitly stated and the 54 seen. The (A1) can be awarded only if their conclusion is consistent with their equation and it lies on the line.

\n

The use of 41.8 as their c value precludes awarding (A1).

\n

 

\n

OR

\n

54 = 0.875(14) + 41.75      (M1)

\n

54 = 54

\n

Note: Award (M1) for their correct substitution into their regression line. Follow through from parts (a)(i) and (b)(i).

\n

 

\n

and so the mean point lies on the regression line     (A1)

\n

Note: Do not award (A1) unless the conclusion is explicitly stated. Follow through from part (a). 

\n

The use of 41.8 as their c value precludes the awarding of (A1).

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

y = 0.875(17) + 41.75      (M1)

\n

Note: Award (M1) for correct substitution into their regression line.

\n

 

\n

= 56.6   (56.625)      (A1)(ft)(G2)

\n

Note: Follow through from part (b)(i).

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

the estimate is valid      (A1)

\n

since this is interpolation and the correlation coefficient is large enough      (R1)

\n

OR

\n

the estimate is not valid      (A1)

\n

since the correlation coefficient is not large enough      (R1)

\n

Note: Do not award (A1)(R0). The (R1) may be awarded for reasoning based on strength of correlation, but do not accept “correlation coefficient is not strong enough” or “correlation is not large enough”.

\n

Award (A0)(R0) for this method if no numerical answer to part (a)(iii) is seen.

\n

 

\n

[2 marks]

\n
c.ii.
\n
\n

\n\n|\n\n\n\n56.6\n\n65\n\n\n65\n\n\n\n|\n\n×\n100\n      (M1)

\n

Note: Award (M1) for correct substitution into percentage error formula. Follow through from part (c)(i).

\n

 

\n

= 12.9  (%)(12.9230…)      (A1)(ft)(G2)

\n

Note: Follow through from part (c)(i). Condone use of percentage symbol.
Award (G0) for an answer of −12.9 with no working.

\n

 

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "18N.2.SL.TZ0.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The number of taxis arriving at Cardiff Central railway station can be modelled by a Poisson distribution. During busy periods of the day, taxis arrive at a mean rate of 5.3 taxis every 10 minutes. Let T represent a random 10 minute busy period.

\n
\n

Find the probability that exactly 4 taxis arrive during T.

\n
[2]
\n
a.i.
\n
\n

Find the most likely number of taxis that would arrive during T.

\n
[2]
\n
a.ii.
\n
\n

Given that more than 5 taxis arrive during T, find the probability that exactly 7 taxis arrive during T.

\n
[3]
\n
a.iii.
\n
\n

During quiet periods of the day, taxis arrive at a mean rate of 1.3 taxis every 10 minutes.

\n

Find the probability that during a period of 15 minutes, of which the first 10 minutes is busy and the next 5 minutes is quiet, that exactly 2 taxis arrive.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

\nX\n\n\nPo\n\n\n(\n\n5.3\n\n)\n\n

\n

\n\nP\n\n\n(\n\nX\n=\n4\n\n)\n\n=\n\n\n\ne\n\n\n\n5.3\n\n\n\n\n\n\n\n\n5.3\n\n4\n\n\n\n\n4\n\n!\n\n\n\n     (M1)

\n

= 0.164      A1

\n

[2 marks]

\n
a.i.
\n
\n

METHOD 1

\n

listing probabilities (table or graph)      M1

\n

mode X = 5 (with probability 0.174)     A1

\n

Note: Award M0A0 for 5 (taxis) or mode = 5 with no justification.

\n

 

\n

METHOD 2

\n

mode is the integer part of mean      R1

\n

E(X) = 5.3 ⇒ mode = 5      A1

\n

Note: Do not allow R0A1.

\n

[2 marks]

\n
a.ii.
\n
\n

attempt at conditional probability       (M1)

\n

\n\n\n\nP\n\n\n(\n\nX\n=\n7\n\n)\n\n\n\n\nP\n\n\n(\n\nX\n\n6\n\n)\n\n\n\n or equivalent \n\n(\n\n=\n\n\n0.1163\n\n\n\n0.4365\n\n\n\n\n)\n\n      A1

\n

= 0.267       A1

\n

[3 marks]

\n
a.iii.
\n
\n

METHOD 1

\n

the possible arrivals are (2,0), (1,1), (0,2)       (A1)

\n

\nY\n\n\nPo\n\n\n(\n\n0.65\n\n)\n\n     A1

\n

attempt to compute, using sum and product rule,      (M1)

\n

0.070106… × 0.52204… + 0.026455… × 0.33932… + 0.0049916… × 0.11028…      (A1)(A1)

\n

Note: Award A1 for one correct product and A1 for two other correct products.

\n

= 0.0461       A1

\n

[6 marks]

\n

 

\n

METHOD 2

\n

recognising a sum of 2 independent Poisson variables eg Z = X + Y      R1

\n

\nλ\n=\n5.3\n+\n\n\n1.3\n\n2\n\n

\n

P(Z = 2) = 0.0461     (M1)A3

\n

[6 marks]

\n

 

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.AHL.TZ2.H_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

A discrete random variable \nX\n follows a Poisson distribution \n\nPo\n\n(\nμ\n)\n.

\n
\n

Show that \n\nP\n\n(\nX\n=\nx\n+\n1\n)\n=\n\nμ\n\nx\n+\n1\n\n\n×\n\nP\n\n(\nX\n=\nx\n)\n,\n\n \n\nx\n\n\nN\n\n.

\n
[3]
\n
a.
\n
\n

Given that \n\nP\n\n(\nX\n=\n2\n)\n=\n0.241667\n and \n\nP\n\n(\nX\n=\n3\n)\n=\n0.112777\n, use part (a) to find the value of \nμ\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\nP\n\n(\nX\n=\nx\n+\n1\n)\n=\n\n\n\n\nμ\n\nx\n+\n1\n\n\n\n\n\n(\nx\n+\n1\n)\n!\n\n\n\n\n\ne\n\n\n\nμ\n\n\n\n    A1

\n

\n=\n\nμ\n\nx\n+\n1\n\n\n×\n\n\n\n\nμ\nx\n\n\n\n\nx\n!\n\n\n\n\n\ne\n\n\n\nμ\n\n\n\n    M1A1

\n

\n=\n\nμ\n\nx\n+\n1\n\n\n×\n\nP\n\n(\nX\n=\nx\n)\n    AG

\n

METHOD 2

\n

\n\nμ\n\nx\n+\n1\n\n\n×\n\nP\n\n(\nX\n=\nx\n)\n=\n\nμ\n\nx\n+\n1\n\n\n×\n\n\n\n\nμ\nx\n\n\n\n\nx\n!\n\n\n\n\n\ne\n\n\n\nμ\n\n\n\n    A1

\n

\n=\n\n\n\n\nμ\n\nx\n+\n1\n\n\n\n\n\n(\nx\n+\n1\n)\n!\n\n\n\n\n\ne\n\n\n\nμ\n\n\n\n    M1A1

\n

\n=\n\nP\n\n(\nX\n=\nx\n+\n1\n)\n    AG

\n

METHOD 3

\n

\n\n\n\nP\n\n(\nX\n=\nx\n+\n1\n)\n\n\n\nP\n\n(\nX\n=\nx\n)\n\n\n=\n\n\n\n\n\n\nμ\n\nx\n+\n1\n\n\n\n\n\n(\nx\n+\n1\n)\n!\n\n\n\n\n\ne\n\n\n\nμ\n\n\n\n\n\n\n\n\n\nμ\nx\n\n\n\n\nx\n!\n\n\n\n\n\ne\n\n\n\nμ\n\n\n\n\n\n    (M1)

\n

\n=\n\n\n\n\nμ\n\nx\n+\n1\n\n\n\n\n\n\n\nμ\nx\n\n\n\n\n×\n\n\nx\n!\n\n\n(\nx\n+\n1\n)\n!\n\n\n    A1

\n

\n=\n\nμ\n\nx\n+\n1\n\n\n    A1

\n

and so \n\nP\n\n(\nX\n=\nx\n+\n1\n)\n=\n\nμ\n\nx\n+\n1\n\n\n×\n\nP\n\n(\nX\n=\nx\n)\n     AG

\n

[3 marks]

\n
a.
\n
\n

\n\nP\n\n(\nX\n=\n3\n)\n=\n\nμ\n3\n\n\n\nP\n\n(\nX\n=\n2\n)\n\n \n\n\n(\n\n0.112777\n=\n\nμ\n3\n\n\n0.241667\n\n)\n\n    A1

\n

attempting to solve for \nμ\n     (M1)

\n

\nμ\n=\n1.40\n    A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.2.AHL.TZ0.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

All lengths in this question are in metres.

\n

Let \nf\n(\nx\n)\n=\n\n0.8\n\n\nx\n2\n\n\n+\n0.5\n, for \n\n0.5\n\nx\n\n0.5\n. Mark uses \nf\n(\nx\n)\n as a model to create a barrel. The region enclosed by the graph of \nf\n, the \nx\n-axis, the line \nx\n=\n\n0.5\n and the line \nx\n=\n0.5\n is rotated 360° about the \nx\n-axis. This is shown in the following diagram.

\n

\"N16/5/MATME/SP2/ENG/TZ0/06\"

\n
\n

Use the model to find the volume of the barrel.

\n
[3]
\n
a.
\n
\n

The empty barrel is being filled with water. The volume V   m 3  of water in the barrel after t minutes is given by V = 0.8 ( 1 e 0.1 t ) . How long will it take for the barrel to be half-full?

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to substitute correct limits or the function into the formula involving

\n

y 2

\n

eg π 0.5 0.5 y 2 d x ,   π ( 0.8 x 2 + 0.5 ) 2 d x

\n

0.601091

\n

volume = 0.601   ( m 3 )      A2     N3

\n

[3 marks]

\n
a.
\n
\n

attempt to equate half their volume to V     (M1)

\n

eg 0.30055 = 0.8 ( 1 e 0.1 t ) , graph

\n

4.71104

\n

4.71 (minutes)     A2     N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.2.SL.TZ0.S_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis", "ahl-5-17-areas-under-curve-onto-y-axis-volume-of-revolution-(about-x-and-y-axes)" ] }, { "Question": "
\n

Packets of biscuits are produced by a machine. The weights \nX\n, in grams, of packets of biscuits can be modelled by a normal distribution where \nX\n\n\nN\n\n(\nμ\n,\n\n \n\n\n\nσ\n2\n\n\n)\n. A packet of biscuits is considered to be underweight if it weighs less than 250 grams.

\n
\n

The manufacturer makes the decision that the probability that a packet is underweight should be 0.002. To do this \nμ\n is increased and \nσ\n remains unchanged.

\n
\n

The manufacturer is happy with the decision that the probability that a packet is underweight should be 0.002, but is unhappy with the way in which this was achieved. The machine is now adjusted to reduce \nσ\n and return \nμ\n to 253.

\n
\n

Given that \nμ\n=\n253\n and \nσ\n=\n1.5\n find the probability that a randomly chosen packet of biscuits is underweight.

\n
[2]
\n
a.
\n
\n

Calculate the new value of \nμ\n giving your answer correct to two decimal places.

\n
[3]
\n
b.
\n
\n

Calculate the new value of \nσ\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nP\n\n(\nX\n<\n250\n)\n=\n0.0228\n     (M1)A1

\n

[2 marks]

\n
a.
\n
\n

\n\n\n250\n\nμ\n\n\n1.5\n\n\n=\n\n2.878\n\n     (M1)(A1)

\n

\n\nμ\n=\n254.32\n     A1

\n

 

\n

Notes:     Only award A1 here if the correct 2dp answer is seen. Award M0 for use of \n\n\n1.5\n2\n\n\n.

\n

 

\n

[3 marks]

\n
b.
\n
\n

\n\n\n250\n\n253\n\nσ\n\n=\n\n2.878\n\n     (A1)

\n

\n\nσ\n=\n1.04\n     A1

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.AHL.TZ2.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

The following graph shows the two parts of the curve defined by the equation \n\n\nx\n2\n\n\ny\n=\n5\n\n\n\ny\n4\n\n\n, and the normal to the curve at the point P(2 , 1).

\n

\n

 

\n
\n

Show that there are exactly two points on the curve where the gradient is zero.

\n
[7]
\n
a.
\n
\n

Find the equation of the normal to the curve at the point P.

\n
[5]
\n
b.
\n
\n

The normal at P cuts the curve again at the point Q. Find the x -coordinate of Q.

\n
[3]
\n
c.
\n
\n

The shaded region is rotated by 2 π about the y -axis. Find the volume of the solid formed.

\n
[7]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

differentiating implicitly:       M1

\n

2 x y + x 2 d y d x = 4 y 3 d y d x      A1A1

\n

Note: Award A1 for each side.

\n

if  d y d x = 0  then either  x = 0 or  y = 0        M1A1

\n

x = 0  two solutions for  y ( y = ± 5 4 )       R1

\n

y = 0  not possible (as 0 ≠ 5)     R1

\n

hence exactly two points      AG

\n

Note: For a solution that only refers to the graph giving two solutions at   x = 0  and no solutions for  y = 0 award R1 only.

\n

[7 marks]

\n
a.
\n
\n

at (2, 1)   4 + 4 d y d x = 4 d y d x      M1

\n

d y d x = 1 2      (A1)

\n

gradient of normal is 2       M1

\n

1 = 4 + c       (M1)

\n

equation of normal is  y = 2 x 3      A1

\n

[5 marks]

\n
b.
\n
\n

substituting      (M1)

\n

x 2 ( 2 x 3 ) = 5 ( 2 x 3 ) 4 or  ( y + 3 2 ) 2 y = 5 y 4        (A1)

\n

x = 0.724       A1

\n

[3 marks]

\n
c.
\n
\n

recognition of two volumes      (M1)

\n

volume  1 = π 1 5 4 5 y 4 y d y ( = 101 π = 3.178 )       M1A1A1

\n

Note: Award M1 for attempt to use  π x 2 d y A1 for limits, A1 for  5 y 4 y  Condone omission of π at this stage.

\n

volume 2

\n

EITHER

\n

= 1 3 π × 2 2 × 4 ( = 16.75 )      (M1)(A1)

\n

OR

\n

= π 3 1 ( y + 3 2 ) 2 d y ( = 16 π 3 = 16.75 )      (M1)(A1)

\n

THEN

\n

total volume = 19.9      A1

\n

[7 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18M.2.AHL.TZ1.H_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

A curve C is given by the implicit equation \nx\n+\ny\n\n\ncos\n\n\n(\n\nx\ny\n\n)\n\n=\n0\n.

\n
\n

The curve \nx\ny\n=\n\n\nπ\n2\n\n intersects C at P and Q.

\n
\n

Show that  d y d x = ( 1 + y sin ( x y ) 1 + x sin ( x y ) ) .

\n
[5]
\n
a.
\n
\n

Find the coordinates of P and Q.

\n
[4]
\n
b.i.
\n
\n

Given that the gradients of the tangents to C at P and Q are m1 and m2 respectively, show that m1 × m2 = 1.

\n
[3]
\n
b.ii.
\n
\n

Find the coordinates of the three points on C, nearest the origin, where the tangent is parallel to the line  y = x .

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt at implicit differentiation      M1

\n

1 + d y d x + ( y + x d y d x ) sin ( x y ) = 0      A1M1A1

\n

Note: Award A1 for first two terms. Award M1 for an attempt at chain rule A1 for last term.

\n

( 1 + x sin ( x y ) ) d y d x = 1 y sin ( x y )      A1

\n

d y d x = ( 1 + y sin ( x y ) 1 + x sin ( x y ) )      AG

\n

[5 marks]

\n
a.
\n
\n

EITHER

\n

when  x y = π 2 , cos x y = 0      M1

\n

x + y = 0     (A1)

\n

OR

\n

x π 2 x cos ( π 2 ) = 0  or equivalent      M1

\n

x π 2 x = 0      (A1)

\n

THEN

\n

therefore  x 2 = π 2 ( x = ± π 2 ) ( x = ± 1.25 )      A1

\n

P ( π 2 , π 2 ) , Q ( π 2 , π 2 ) or  P ( 1.25 , 1.25 ) , Q ( 1.25 , 1.25 )      A1

\n

[4 marks]

\n
b.i.
\n
\n

m1 = ( 1 π 2 × 1 1 + π 2 × 1 )      M1A1

\n

m ( 1 + π 2 × 1 1 π 2 × 1 )      A1

\n

mm= 1     AG

\n

Note: Award M1A0A0 if decimal approximations are used.
Note: No FT applies.

\n

[3 marks]

\n
b.ii.
\n
\n

equate derivative to −1    M1

\n

( y x ) sin ( x y ) = 0      (A1)

\n

y = x , sin ( x y ) = 0      R1

\n

in the first case, attempt to solve  2 x = cos ( x 2 )      M1

\n

(0.486,0.486)      A1

\n

in the second case,  sin ( x y ) = 0 x y = 0 and  x + y = 1      (M1)

\n

(0,1), (1,0)      A1

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.AHL.TZ2.H_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-14-implicit-functions-related-rates-optimisation" ] }, { "Question": "
\n

A solid right circular cone has a base radius of 21 cm and a slant height of 35 cm.
A smaller right circular cone has a height of 12 cm and a slant height of 15 cm, and is removed from the top of the larger cone, as shown in the diagram.

\n

\n
\n

Calculate the radius of the base of the cone which has been removed.

\n
[2]
\n
a.
\n
\n

Calculate the curved surface area of the cone which has been removed.

\n
[2]
\n
b.
\n
\n

Calculate the curved surface area of the remaining solid.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\n\n15\n\n2\n\n\n\n\n\n\n12\n\n2\n\n\n\n     (M1)

\n

Note: Award (M1) for correct substitution into Pythagoras theorem.

\n

OR

\n

\n\n\n\nradius\n\n\n\n21\n\n\n=\n\n\n15\n\n\n35\n\n\n     (M1)

\n

Note: Award (M1) for a correct equation.

\n

= 9 (cm)     (A1) (C2)

\n

[2 marks]

\n
a.
\n
\n

\nπ\n×\n9\n×\n15\n      (M1)

\n

Note: Award (M1) for their correct substitution into curved surface area of a cone formula.

\n

\n=\n424\n\n\n\nc\n\n\n\n\nm\n\n2\n\n\n\n\n\n\n\n\n(\n\n135\nπ\n,\n\n\n424.115...\n\nc\n\n\n\n\nm\n\n2\n\n\n\n)\n\n     (A1)(ft) (C2)

\n

Note: Follow through from part (a).

\n

[2 marks]

\n
b.
\n
\n

\nπ\n×\n21\n×\n35\n\n424.115...\n     (M1)

\n

Note: Award (M1) for their correct substitution into curved surface area of a cone formula and for subtracting their part (b).

\n

\n=\n1880\n\n\n\nc\n\n\n\n\nm\n\n2\n\n\n\n\n\n\n\n\n(\n\n600\nπ\n,\n\n\n1884.95...\n\nc\n\n\n\n\nm\n\n2\n\n\n\n)\n\n     (A1)(ft) (C2)

\n

Note: Follow through from part (b).

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ1.T_14", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

The curve \nC\n is defined by equation \nx\ny\n\nln\n\ny\n=\n1\n,\n\n \n\ny\n>\n0\n.

\n
\n

Find \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n in terms of \nx\n and \ny\n.

\n
[4]
\n
a.
\n
\n

Determine the equation of the tangent to \nC\n at the point \n\n(\n\n\n2\n\ne\n\n\n,\n\n e\n\n\n)\n\n

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ny\n+\nx\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n\n1\ny\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n     M1A1A1

\n

 

\n

Note:     Award A1 for the first two terms, A1 for the third term and the 0.

\n

 

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n\n\ny\n2\n\n\n\n\n1\n\nx\ny\n\n\n     A1

\n

 

\n

Note:     Accept \n\n\n\n\n\ny\n2\n\n\n\n\nln\n\ny\n\n\n.

\n

 

\n

Note:     Accept \n\n\n\ny\n\n\nx\n\n\n1\ny\n\n\n\n.

\n

 

\n

[4 marks]

\n
a.
\n
\n

\n\n\nm\nT\n\n\n=\n\n\n\n\n\ne\n\n2\n\n\n\n\n1\n\n\ne\n\n×\n\n2\n\ne\n\n\n\n\n     (M1)

\n

\n\n\nm\nT\n\n\n=\n\n\n\n\ne\n\n2\n\n\n     (A1)

\n

\ny\n\n\ne\n\n=\n\n\n\n\ne\n\n2\n\n\nx\n+\n2\n\ne\n\n

\n

\n\n\n\n\ne\n\n2\n\n\nx\n\ny\n+\n3\n\ne\n\n=\n0\n or equivalent     A1

\n

 

\n

Note:     Accept \ny\n=\n\n7.39\nx\n+\n8.15\n.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.AHL.TZ1.H_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

A pan, in which to cook a pizza, is in the shape of a cylinder. The pan has a diameter of 35 cm and a height of 0.5 cm.

\n

\"M17/5/MATSD/SP2/ENG/TZ1/04\"

\n
\n

A chef had enough pizza dough to exactly fill the pan. The dough was in the shape of a sphere.

\n
\n

The pizza was cooked in a hot oven. Once taken out of the oven, the pizza was placed in a dining room.

\n

The temperature, \nP\n, of the pizza, in degrees Celsius, °C, can be modelled by

\n

\nP\n(\nt\n)\n=\na\n\n(\n2.06\n\n)\n\n\nt\n\n\n\n+\n19\n,\n\n \n\nt\n\n0\n

\n

where \na\n is a constant and \nt\n is the time, in minutes, since the pizza was taken out of the oven.

\n

When the pizza was taken out of the oven its temperature was 230 °C.

\n
\n

The pizza can be eaten once its temperature drops to 45 °C.

\n
\n

Calculate the volume of this pan.

\n
[3]
\n
a.
\n
\n

Find the radius of the sphere in cm, correct to one decimal place.

\n
[4]
\n
b.
\n
\n

Find the value of \na\n.

\n
[2]
\n
c.
\n
\n

Find the temperature that the pizza will be 5 minutes after it is taken out of the oven.

\n
[2]
\n
d.
\n
\n

Calculate, to the nearest second, the time since the pizza was taken out of the oven until it can be eaten.

\n
[3]
\n
e.
\n
\n

In the context of this model, state what the value of 19 represents.

\n
[1]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n(\nV\n=\n)\n\n \n\nπ\n×\n\n\n\n(17.5)\n\n2\n\n\n×\n0.5\n     (A1)(M1)

\n

 

\n

Notes:     Award (A1) for 17.5 (or equivalent) seen.

\n

Award (M1) for correct substitutions into volume of a cylinder formula.

\n

 

\n

\n=\n481\n\n c\n\n\n\n\nm\n\n3\n\n\n\n \n\n(\n481.056\n\n\n c\n\n\n\n\nm\n\n3\n\n\n,\n\n \n\n153.125\nπ\n\n c\n\n\n\n\nm\n\n3\n\n\n)\n     (A1)(G2)

\n

[3 marks]

\n
a.
\n
\n

\n\n4\n3\n\n×\nπ\n×\n\n\nr\n3\n\n\n=\n481.056\n\n     (M1)

\n

 

\n

Note:     Award (M1) for equating their answer to part (a) to the volume of sphere.

\n

 

\n

\n\n\nr\n3\n\n\n=\n\n\n3\n×\n481.056\n\n\n\n4\nπ\n\n\n\n \n\n(\n=\n114.843\n\n)\n     (M1)

\n

 

\n

Note:     Award (M1) for correctly rearranging so \n\n\nr\n3\n\n\n is the subject.

\n

 

\n

\nr\n=\n4.86074\n\n\n (cm)\n\n     (A1)(ft)(G2)

\n

 

\n

Note:     Award (A1) for correct unrounded answer seen. Follow through from part (a).

\n

 

\n

\n=\n4.9\n\n (cm)\n\n     (A1)(ft)(G3)

\n

 

\n

Note:     The final (A1)(ft) is awarded for rounding their unrounded answer to one decimal place.

\n

 

\n

[4 marks]

\n
b.
\n
\n

\n230\n=\na\n\n(\n2.06\n\n)\n0\n\n\n+\n19\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution.

\n

 

\n

\na\n=\n211\n     (A1)(G2)

\n

[2 marks]

\n
c.
\n
\n

\n(\nP\n=\n)\n\n \n\n211\n×\n\n(\n2.06\n\n)\n\n\n5\n\n\n\n+\n19\n      (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into the function, \nP\n(\nt\n)\n. Follow through from part (c). The negative sign in the exponent is required for correct substitution.

\n

 

\n

\n=\n24.7\n (°C) \n(\n24.6878\n\n (°C))     (A1)(ft)(G2)

\n

[2 marks]

\n
d.
\n
\n

\n45\n=\n211\n×\n\n(\n2.06\n\n)\n\n\nt\n\n\n\n+\n19\n     (M1)

\n

 

\n

Note:     Award (M1) for equating 45 to the exponential equation and for correct substitution (follow through for their \na\n in part (c)).

\n

 

\n

\n(\nt\n=\n)\n\n \n\n2.89711\n\n     (A1)(ft)(G1)

\n

\n174\n\n (seconds) \n\n\n(\n\n173.826\n\n\n (seconds)\n\n\n)\n\n     (A1)(ft)(G2)

\n

 

\n

Note:     Award final (A1)(ft) for converting their \n\n2.89711\n\n\n minutes into seconds.

\n

 

\n

[3 marks]

\n
e.
\n
\n

the temperature of the (dining) room     (A1)

\n

OR

\n

the lowest final temperature to which the pizza will cool     (A1)

\n

[1 mark]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "17M.2.SL.TZ1.T_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

The age, L, in years, of a wolf can be modelled by the normal distribution L ~ N(8, 5).

\n
\n

Find the probability that a wolf selected at random is at least 5 years old.

\n
[2]
\n
a.
\n
\n

Eight wolves are independently selected at random and their ages recorded.

\n

Find the probability that more than six of these wolves are at least 5 years old.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

P(L ≥ 5) = 0.910      (M1)A1

\n

[2 marks]

\n
a.
\n
\n

X is the number of wolves found to be at least 5 years old recognising binomial distribution      M1

\n

X ~ B(8, 0.910…)

\n

P(X > 6) = 1 − P(X ≤ 6)      (M1)

\n

= 0.843       A1

\n

Note: Award M1A0 for finding P(X ≥ 6).

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.AHL.TZ1.H_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n2\n\n\nx\n2\n\n\n\n5\nx\n\n12\n\n\nx\n+\n2\n\n\n\n,\n\n\n\nx\n\n\nR\n\n\n,\n\n\n\nx\n\n\n2\n.

\n
\n

Find all the intercepts of the graph of \nf\n\n(\nx\n)\n\n with both the \nx\n and \ny\n axes.

\n
[4]
\n
a.
\n
\n

Write down the equation of the vertical asymptote.

\n
[1]
\n
b.
\n
\n

As \nx\n\n±\n\n the graph of \nf\n\n(\nx\n)\n\n approaches an oblique straight line asymptote.

\n

Divide \n2\n\n\nx\n2\n\n\n\n5\nx\n\n12\n by \nx\n+\n2\n to find the equation of this asymptote.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

\nx\n=\n0\n\ny\n=\n\n6\n intercept on the \ny\n axes is (0, −6)     A1

\n

\n2\n\n\nx\n2\n\n\n\n5\nx\n\n12\n=\n0\n\n\n(\n\n2\nx\n+\n3\n\n)\n\n\n(\n\nx\n\n4\n\n)\n\n=\n0\n\nx\n=\n\n\n\n3\n\n2\n\n\n\n\nor\n\n\n\n\n4\n\n      M1

\n

intercepts on the \nx\n axes are \n\n(\n\n\n\n\n3\n\n2\n\n\n,\n\n\n\n0\n\n)\n\n\n\n\nand\n\n\n\n\n(\n\n4\n\n,\n\n\n\n0\n\n)\n\n     A1A1

\n

[4 marks]

\n
a.
\n
\n

\nx\n=\n\n2\n    A1

\n

[1 mark]

\n
b.
\n
\n

\nf\n(\nx\n)\n=\n2\nx\n\n9\n+\n\n6\n\nx\n+\n2\n\n\n          M1A1

\n

So equation of asymptote is \ny\n=\n2\nx\n\n9\n          M1A1

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXM.1.AHL.TZ0.5", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-13-rational-functions" ] }, { "Question": "
\n

The random variable X has a normal distribution with mean μ = 50 and variance σ 2 = 16 .

\n
\n

Sketch the probability density function for X, and shade the region representing P(μ − 2σ < X < μ + σ).

\n
[2]
\n
a.
\n
\n

Find the value of P(μ − 2σ < X < μ + σ).

\n
[2]
\n
b.
\n
\n

Find the value of k for which P(μkσ < X < μ + kσ) = 0.5.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

normal curve centred on 50      A1

\n

vertical lines at \nx\n = 42 and \nx\n = 54, with shading in between       A1

\n

[2 marks]

\n
a.
\n
\n

P(42 X < 54) (= P(− 2 Z < 1))     (M1)

\n

= 0.819       A1

\n

[2 marks]

\n
b.
\n
\n

P(μ − kσ < X < μ + kσ) = 0.5 ⇒ P(X < μ + kσ) = 0.75      (M1)

\n

k = 0.674       A1

\n

Note: Award M1A0 for k = −0.674.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.AHL.TZ2.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

A camera at point C is 3 m from the edge of a straight section of road as shown in the following diagram. The camera detects a car travelling along the road at t = 0. It then rotates, always pointing at the car, until the car passes O, the point on the edge of the road closest to the camera.

\n

\n

A car travels along the road at a speed of 24 ms−1. Let the position of the car be X and let OĈX = θ.

\n

Find d θ d t , the rate of rotation of the camera, in radians per second, at the instant the car passes the point O .

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

let OX =  x

\n

METHOD 1

\n

d x d t = 24    (or −24)       (A1)

\n

d θ d t = d x d t × d θ d x        (M1)

\n

3 tan θ = x        A1

\n

EITHER

\n

3 se c 2 θ = d x d θ        A1

\n

d θ d t = 24 3 se c 2 θ

\n

attempt to substitute for θ = 0 into their differential equation       M1

\n

OR

\n

θ = arctan ( x 3 )

\n

d θ d x = 1 3 × 1 1 + x 2 9        A1

\n

d θ d t = 24 × 1 3 ( 1 + x 2 9 )

\n

attempt to substitute for x = 0 into their differential equation       M1

\n

THEN

\n

d θ d t = 24 3 = 8   (rad s−1)       A1

\n

Note: Accept −8 rad s−1.

\n

 

\n

METHOD 2

\n

d x d t = 24    (or −24)       (A1)

\n

3 tan θ = x        A1

\n

attempt to differentiate implicitly with respect to t        M1

\n

3 se c 2 θ × d θ d t = d x d t       A1

\n

d θ d t = 24 3 se c 2 θ

\n

attempt to substitute for θ = 0 into their differential equation       M1

\n

d θ d t = 24 3 = 8 (rad s−1)       A1

\n

Note: Accept −8 rad s−1.

\n

Note: Can be done by consideration of CX, use of Pythagoras.

\n

 

\n

METHOD 3

\n

let the position of the car be at time t be d 24 t from O       (A1)

\n

tan θ = d 24 t 3 ( = d 3 8 t )        M1

\n

Note: For  tan θ = 24 t 3 award A0M1 and follow through.

\n

EITHER

\n

attempt to differentiate implicitly with respect to t        M1

\n

se c 2 θ d θ d t = 8        A1

\n

attempt to substitute for θ = 0 into their differential equation       M1

\n

OR

\n

θ = arctan ( d 3 8 t )        M1

\n

d θ d t = 8 1 + ( d 3 8 t ) 2        A1

\n

at O,  t = d 24        A1

\n

THEN

\n

d θ d t = 8        A1

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ1.H_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-14-implicit-functions-related-rates-optimisation" ] }, { "Question": "
\n

Let \nl\n be the tangent to the curve \ny\n=\nx\n\n\n\ne\n\n\n2\nx\n\n\n\n at the point (1, \n\n\n\ne\n\n2\n\n\n).

\n

Find the coordinates of the point where \nl\n meets the \nx\n-axis.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

equation of tangent is \ny\n=\n22.167\n\nx\n\n14.778\n\n  OR  \ny\n=\n\n7.389\n\n=\n22.167\n\n\n(\n\nx\n\n1\n\n)\n\n       (M1)(A1)

\n

meets the \nx\n-axis when \ny\n=\n0\n

\n

\nx\n=\n0.667\n

\n

meets \nx\n-axis at (0.667, 0)\n\n(\n\n=\n\n(\n\n\n2\n3\n\n,\n\n\n0\n\n)\n\n\n)\n\n       A1A1

\n

Note: Award A1 for \nx\n=\n\n2\n3\n\n or \nx\n=\n0.667\n seen and A1 for coordinates (\nx\n, 0) given.

\n

 

\n

METHOD 1

\n

Attempt to differentiate       (M1)

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n\ne\n\n\n2\nx\n\n\n\n+\n2\nx\n\n\n\ne\n\n\n2\nx\n\n\n\n

\n

when \nx\n=\n1\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n3\n\n\n\ne\n\n2\n\n\n       (M1)

\n

equation of the tangent is \ny\n\n\n\n\ne\n\n2\n\n\n=\n3\n\n\n\ne\n\n2\n\n\n\n(\n\nx\n\n1\n\n)\n\n

\n

\ny\n=\n3\n\n\n\ne\n\n2\n\n\nx\n\n2\n\n\n\ne\n\n2\n\n\n

\n

meets \nx\n-axis at \nx\n=\n\n2\n3\n\n

\n

\n\n\n(\n\n\n2\n3\n\n,\n\n\n0\n\n)\n\n\n       A1A1

\n

Note: Award A1 for \nx\n=\n\n2\n3\n\n or \nx\n=\n0.667\n seen and A1 for coordinates (\nx\n, 0) given.

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.2.AHL.TZ1.H_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

Consider the function \nf\n  defined by \nf\n(\nx\n)\n=\n\n\n\ne\n\nx\n\n\nsin\n\nx\n,\n\n \n\n0\n\nx\n\nπ\n.

\n
\n

The curvature at any point \n(\nx\n,\n\n \n\ny\n)\n on a graph is defined as \nκ\n=\n\n\n\n|\n\n\n\n\n\n\nd\n\n2\n\n\ny\n\n\n\nd\n\n\n\nx\n2\n\n\n\n\n\n|\n\n\n\n\n\n\n\n(\n\n1\n+\n\n\n\n\n(\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n)\n\n\n2\n\n\n\n)\n\n\n\n\n3\n2\n\n\n\n\n\n\n.

\n
\n

Show that the function f has a local maximum value when x = 3 π 4 .

\n
[2]
\n
c.
\n
\n

Find the x -coordinate of the point of inflexion of the graph of f .

\n
[2]
\n
d.
\n
\n

Sketch the graph of f , clearly indicating the position of the local maximum point, the point of inflexion and the axes intercepts.

\n
[3]
\n
e.
\n
\n

Find the area of the region enclosed by the graph of f and the x -axis.

\n

The curvature at any point ( x ,   y ) on a graph is defined as κ = | d 2 y d x 2 | ( 1 + ( d y d x ) 2 ) 3 2 .

\n
[6]
\n
f.
\n
\n

Find the value of the curvature of the graph of f at the local maximum point.

\n
[3]
\n
g.
\n
\n

Find the value κ for x = π 2 and comment on its meaning with respect to the shape of the graph.

\n
[2]
\n
h.
\n
", "Markscheme": "
\n

d y d x = e 3 π 4 ( sin 3 π 4 + cos 3 π 4 ) = 0    R1

\n

d 2 y d x 2 = 2 e 3 π 4 cos 3 π 4 < 0    R1

\n

hence maximum at x = 3 π 4      AG

\n

[2 marks]

\n
c.
\n
\n

d 2 y d x 2 = 0 2 e x cos x = 0    M1

\n

x = π 2    A1

\n

 

\n

Note: Award M1A0 if extra zeros are seen.

\n

 

\n

[2 marks]

\n
d.
\n
\n

\"N16/5/MATHL/HP1/ENG/TZ0/11.e/M\"

\n

correct shape and correct domain     A1

\n

max at x = 3 π 4 , point of inflexion at x = π 2      A1

\n

zeros at x = 0 and x = π      A1

\n

 

\n

Note: Penalize incorrect domain with first A mark; allow FT from (d) on extra points of inflexion.

\n

 

\n

[3 marks]

\n
e.
\n
\n

EITHER

\n

0 x e x sin x d x = [ e x sin x ] 0 π 0 π e x cos x d x    M1A1

\n

0 π e x sin x d x = [ e x sin x ] 0 π ( [ e x cos x ] 0 x + 0 π e x sin x d x )    A1

\n

OR

\n

0 π e x sin x d x = [ e x cos x ] 0 π + 0 π e x cos x d x    M1A1

\n

0 π e x sin x d x = [ e x cos x ] 0 π + ( [ e x sin x ] 0 π 0 π e x sin x d x )    A1

\n

THEN

\n

0 π e x sin x d x = 1 2 ( [ e x sin x ] 0 x [ e x cos x ] 0 x )    M1A1

\n

0 π e x sin x d x = 1 2 ( e x + 1 )    A1

\n

[6 marks]

\n
f.
\n
\n

d y d x = 0    (A1)

\n

  d 2 y d x 2 = 2 e 3 π 4 cos 3 π 4 = 2 e 3 π 4 (A1)

\n

κ = | 2 e 3 π 4 | 1 = 2 e 3 π 4    A1

\n

[3 marks]

\n
g.
\n
\n

κ = 0    A1

\n

the graph is approximated by a straight line     R1

\n

[2 marks]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
", "question_id": "16N.1.AHL.TZ0.H_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n\n\nx\n2\n\n\n\n10\nx\n+\n5\n\n\nx\n+\n1\n\n\n\n,\n\n\n\nx\n\n\nR\n\n\n,\n\n\n\nx\n\n\n1\n.

\n
\n

Find the co-ordinates of all stationary points.

\n
[4]
\n
a.
\n
\n

Write down the equation of the vertical asymptote.

\n
[1]
\n
b.
\n
\n

With justification, state if each stationary point is a minimum, maximum or horizontal point of inflection.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n\n(\n\n2\nx\n\n10\n\n)\n\n\n(\n\nx\n+\n1\n\n)\n\n\n\n(\n\n\n\nx\n2\n\n\n\n10\nx\n+\n5\n\n)\n\n1\n\n\n\n\n\n\n(\n\nx\n+\n1\n\n)\n\n\n2\n\n\n\n\n          M1

\n

\n\nf\n\n\n\n(\nx\n)\n\n=\n0\n\n\n\nx\n2\n\n\n+\n2\nx\n\n15\n=\n0\n\n\n(\n\nx\n+\n5\n\n)\n\n\n(\n\nx\n\n3\n\n)\n\n=\n0\n          M1

\n

Stationary points are \n\n(\n\n\n5\n\n,\n\n\n\n\n20\n\n)\n\n\n\n\nand\n\n\n\n\n(\n\n3\n\n,\n\n\n\n\n4\n\n)\n\n         A1A1

\n

[4 marks]

\n
a.
\n
\n

\nx\n=\n\n1\n        A1

\n

[1 mark]

\n
b.
\n
\n

Looking at the nature table

\n

        M1A1

\n

\n\n(\n\n\n5\n\n,\n\n\n\n20\n\n)\n\n is a max and \n\n(\n\n3\n\n,\n\n\n\n4\n\n)\n\n is a min         A1A1

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXM.1.AHL.TZ0.6", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-13-rational-functions" ] }, { "Question": "
\n

The times taken for male runners to complete a marathon can be modelled by a normal distribution with a mean 196 minutes and a standard deviation 24 minutes.

\n
\n

It is found that 5% of the male runners complete the marathon in less than \n\n\nT\n1\n\n\n minutes.

\n
\n

The times taken for female runners to complete the marathon can be modelled by a normal distribution with a mean 210 minutes. It is found that 58% of female runners complete the marathon between 185 and 235 minutes.

\n
\n

Find the probability that a runner selected at random will complete the marathon in less than 3 hours.

\n
[2]
\n
a.
\n
\n

Calculate \n\n\nT\n1\n\n\n.

\n
[2]
\n
b.
\n
\n

Find the standard deviation of the times taken by female runners.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nT\n\nN\n(\n196\n,\n\n \n\n\n\n24\n2\n\n\n)\n

\n

\n\nP\n\n(\nT\n<\n180\n)\n=\n0.252\n     (M1)A1

\n

[2 marks]

\n
a.
\n
\n

\n\nP\n\n(\nT\n<\n\n\nT\n1\n\n\n)\n=\n0.05\n     (M1)

\n

\n\n\nT\n1\n\n\n=\n157\n     A1

\n

[2 marks]

\n
b.
\n
\n

\nF\n\nN\n(\n210\n,\n\n \n\n\n\nσ\n2\n\n\n)\n

\n

\n\nP\n\n(\nF\n<\n235\n)\n=\n0.79\n     (M1)

\n

\n\n\n235\n\n210\n\nσ\n\n=\n0.806421\n or equivalent     (M1)(A1)

\n

\nσ\n=\n31.0\n     A1

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.AHL.TZ1.H_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

A park in the form of a triangle, ABC, is shown in the following diagram. AB is 79 km and BC is 62 km. Angle A\n\n\nB\n\n\n\nC is 52°.

\n

\n
\n

Calculate the length of side AC in km.

\n
[3]
\n
a.
\n
\n

Calculate the area of the park.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(AC2 =) 622 + 792 − 2 × 62 × 79 × cos(52°)     (M1)(A1)

\n

Note: Award (M1) for substituting in the cosine rule formula, (A1) for correct substitution.

\n

63.7  (63.6708…) (km)     (A1) (C3)

\n

[3 marks]

\n
a.
\n
\n

\n\n1\n2\n\n × 62 × 79 × sin(52°)     (M1)(A1)

\n

Note: Award (M1) for substituting in the area of triangle formula, (A1) for correct substitution.

\n

1930 km2  (1929.83…km2)     (A1) (C3)

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ2.T_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A set of data comprises of five numbers \n\n\nx\n\n1\n\n\n\n\n\n,\n\n\n\n\n\nx\n2\n\n\n\n,\n\n\n\n\n\nx\n3\n\n\n\n,\n\n\n\n\n\nx\n4\n\n\n\n,\n\n\n\n\n\nx\n5\n\n\n which have been placed in ascending order.

\n
\n

Recalling definitions, such as the Lower Quartile is the \n\n\nn\n+\n1\n\n4\n\nt\nh\n piece of data with the data placed in order, find an expression for the Interquartile Range.

\n
[2]
\n
a.
\n
\n

Hence, show that a data set with only 5 numbers in it cannot have any outliers.

\n
[5]
\n
b.
\n
\n

Give an example of a set of data with 7 numbers in it that does have an outlier, justify this fact by stating the Interquartile Range.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

\nL\nQ\n=\n\n\n\n\nx\n1\n\n\n+\n\n\nx\n2\n\n\n\n2\n\n\n,\n\n\n\nU\nQ\n=\n\n\n\n\nx\n4\n\n\n+\n\n\nx\n5\n\n\n\n2\n\n\n,\n\n\n\nI\nQ\nR\n=\n\n\n\n\nx\n4\n\n\n+\n\n\nx\n5\n\n\n\n\n\nx\n1\n\n\n\n\n\nx\n2\n\n\n\n2\n\n       M1A1

\n

[2 marks]

\n
a.
\n
\n

\nU\nQ\n+\n1.5\nI\nQ\nR\n=\n1.25\n\n\nx\n4\n\n\n+\n1.25\n\n\nx\n5\n\n\n\n0.75\n\n\nx\n1\n\n\n\n0.75\n\n\nx\n2\n\n\n\n\n\nx\n5\n\n\n      M1A1

\n

Since \n1.25\n\n\nx\n4\n\n\n+\n0.25\n\n\nx\n5\n\n\n\n0.75\n\n\nx\n1\n\n\n+\n0.75\n\n\nx\n2\n\n\n due to the ascending order.      R1

\n

Similarly \nL\nQ\n\n1.5\nI\nQ\nR\n=\n1.25\n\n\nx\n1\n\n\n+\n1.25\n\n\nx\n2\n\n\n\n0.75\n\n\nx\n4\n\n\n\n0.75\n\n\nx\n5\n\n\n\n\n\nx\n1\n\n\n      M1A1

\n

Since \n0.25\n\n\nx\n1\n\n\n+\n1.25\n\n\nx\n2\n\n\n\n0.75\n\n\nx\n3\n\n\n+\n0.75\n\n\nx\n4\n\n\n due to the ascending order.

\n

So there are no outliers for a data set of 5 numbers.      AG

\n

[5 marks]

\n

 

\n
b.
\n
\n

For example 1, 2, 3, 4, 5, 6, 100 where \nI\nQ\nR\n=\n4\n     A1A1

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "EXM.1.SL.TZ0.2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

It is known that 56 % of Infiglow batteries have a life of less than 16 hours, and 94 % have a life less than 17 hours. It can be assumed that battery life is modelled by the normal distribution \n\nN\n\n\n(\n\nμ\n,\n\n\n\n\nσ\n2\n\n\n\n)\n\n.

\n
\n

Find the value of \nμ\n and the value of \nσ\n.

\n
[6]
\n
a.
\n
\n

Find the probability that a randomly selected Infiglow battery will have a life of at least 15 hours.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

use of inverse normal (implied by ±0.1509… or ±1.554…)       (M1)

\n

P(X < 16) = 0.56

\n

\n\n\n\n16\n\nμ\n\nσ\n\n=\n0.1509\n\n      (A1)

\n

P(X < 17) = 0.94

\n

\n\n\n\n17\n\nμ\n\nσ\n\n=\n1.554\n\n      (A1)

\n

attempt to solve a pair of simultaneous equations       (M1)

\n

\nμ\n = 15.9,  \nσ\n = 0.712      A1A1

\n

 

\n

[6 marks]

\n
a.
\n
\n

correctly shaded diagram or intent to find P(X ≥ 15)       (M1)

\n

= 0.895       A1

\n

Note: Accept answers rounding to 0.89 or 0.90. Award M1A0 for the answer 0.9.

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.2.AHL.TZ0.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Harry travelled from the USA to Mexico and changed 700 dollars (USD) into pesos (MXN).

\n

The exchange rate was 1 USD = 18.86 MXN.

\n
\n

On his return, Harry had 2400 MXN to change back into USD.

\n

There was a 3.5 % commission to be paid on the exchange.

\n
\n

Calculate the amount of MXN Harry received.

\n
[2]
\n
a.
\n
\n

Calculate the value of the commission, in MXN, that Harry paid.

\n
[2]
\n
b.
\n
\n

The exchange rate for this exchange was 1 USD = 17.24 MXN.

\n

Calculate the amount of USD Harry received. Give your answer correct to the nearest cent.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

700 × 18.86      (M1)

\n

Note: Award (M1) for multiplication by 18.86.

\n

= 13 200 (13 202) (MXN)      (A1) (C2)

\n

 

\n

[2 marks]

\n
a.
\n
\n

2400 × 0.035       (M1)

\n

Note: Award (M1) for multiplication by 0.035.

\n

= 84 (MXN)     (A1) (C2)

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n\n\n2400\n\n\ntheir part (b)\n\n\n\n17.24\n\n\n      (M1)

\n

Note: Award (M1) for dividing 2400 minus their part (b), by 17.24. Follow through from part (b).

\n

= 134.34 (USD)       (A1)(ft) (C2)

\n

Note: Award at most (M1)(A0) if final answer is not given to nearest cent.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.1.SL.TZ0.T_3", "topics": [], "subtopics": [] }, { "Question": "
\n

Julio is making a wooden pencil case in the shape of a large pencil. The pencil case consists of a cylinder attached to a cone, as shown.

\n

The cylinder has a radius of r cm and a height of 12 cm.

\n

The cone has a base radius of r cm and a height of 10 cm.

\n

\n
\n

Find an expression for the slant height of the cone in terms of r.

\n
[2]
\n
a.
\n
\n

The total external surface area of the pencil case rounded to 3 significant figures is 570 cm2.

\n

Using your graphic display calculator, calculate the value of r.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(slant height2 =) 102 + r 2     (M1)

\n

Note: For correct substitution of 10 and r into Pythagoras’ Theorem.

\n

\n\n\n\n\n10\n\n2\n\n\n+\n\n\nr\n2\n\n\n\n     (A1) (C2)

\n

[2 marks]

\n
a.
\n
\n

\nπ\n\n\nr\n2\n\n\n+\n2\nπ\nr\n×\n12\n+\nπ\nr\n\n100\n+\n\n\nr\n2\n\n\n\n=\n570\n     (M1)(M1)(M1)

\n

Note: Award (M1) for correct substitution in curved surface area of cylinder and area of the base, (M1) for their correct substitution in curved surface area of cone, (M1) for adding their 3 surface areas and equating to 570. Follow through their part (a).

\n

= 4.58   (4.58358...)      (A1)(ft) (C4)

\n

Note: Last line must be seen to award final (A1). Follow through from part (a).

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ2.T_15", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Let \nX\n be a random variable which follows a normal distribution with mean \nμ\n. Given that \n\nP\n\n\n(\n\nX\n<\nμ\n\n5\n\n)\n\n=\n0.2\n , find

\n
\n

\n\nP\n\n\n(\n\nX\n>\nμ\n+\n5\n\n)\n\n.

\n
[2]
\n
a.
\n
\n

\n\nP\n\n\n(\n\nX\n<\nμ\n+\n5\n\n\n|\n\n\nX\n>\nμ\n\n5\n\n\n\n\n)\n\n.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

use of symmetry eg diagram       (M1)

\n

\n\nP\n\n\n(\n\nX\n>\nμ\n+\n5\n\n)\n\n=\n0.2\n       A1

\n

[2 marks]

\n
a.
\n
\n

EITHER

\n

\n\nP\n\n\n(\n\nX\n<\nμ\n+\n5\n\n\n|\n\n\nX\n>\nμ\n\n5\n\n\n\n\n)\n\n=\n\n\n\nP\n\n\n(\n\nX\n>\nμ\n\n5\n\nX\n<\nμ\n+\n5\n\n)\n\n\n\n\nP\n\n\n(\n\nX\n>\nμ\n\n5\n\n)\n\n\n\n       (M1)

\n

      \n=\n\n\n\nP\n\n\n(\n\nμ\n\n5\n<\nX\n<\nμ\n+\n5\n\n)\n\n\n\n\nP\n\n\n(\n\nX\n>\nμ\n\n5\n\n)\n\n\n\n       (A1)

\n

      \n=\n\n\n0.6\n\n\n0.8\n\n\n      A1A1

\n

Note: A1 for denominator is independent of the previous A marks.

\n

OR

\n

use of diagram       (M1)

\n

Note: Only award (M1) if the region \nμ\n\n5\n<\nX\n<\nμ\n+\n5\n is indicated and used.

\n

\n\nP\n\n\n(\n\nX\n>\nμ\n\n5\n\n)\n\n=\n0.8\n      \n\nP\n\n\n(\n\nμ\n\n5\n<\nX\n<\nμ\n+\n5\n\n)\n\n=\n0.6\n       (A1)

\n

Note: Probabilities can be shown on the diagram.

\n

\n=\n\n\n0.6\n\n\n0.8\n\n\n      M1A1

\n

THEN

\n

\n=\n\n3\n4\n\n\n\n\n=\n\n(\n\n0.75\n\n)\n\n      A1

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.AHL.TZ1.H_6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

The principal of a high school is concerned about the effect social media use might be having on the self-esteem of her students. She decides to survey a random sample of 9 students to gather some data. She wants the number of students in each grade in the sample to be, as far as possible, in the same proportion as the number of students in each grade in the school.

\n
\n

The number of students in each grade in the school is shown in table.

\n

\n
\n

In order to select the 3 students from grade 12, the principal lists their names in alphabetical order and selects the 28th, 56th and 84th student on the list.

\n
\n

Once the principal has obtained the names of the 9 students in the random sample, she surveys each student to find out how long they used social media the previous day and measures their self-esteem using the Rosenberg scale. The Rosenberg scale is a number between 10 and 40, where a high number represents high self-esteem.

\n

\n
\n

State the name for this type of sampling technique.

\n
[1]
\n
a.
\n
\n

Show that 3 students will be selected from grade 12.

\n
[3]
\n
b.i.
\n
\n

Calculate the number of students in each grade in the sample.

\n
[2]
\n
b.ii.
\n
\n

State the name for this type of sampling technique.

\n
[1]
\n
c.
\n
\n

Calculate Pearson’s product moment correlation coefficient, \nr\n.

\n
[2]
\n
d.i.
\n
\n

Interpret the meaning of the value of \nr\n in the context of the principal’s concerns.

\n
[1]
\n
d.ii.
\n
\n

Explain why the value of \nr\n makes it appropriate to find the equation of a regression line.

\n
[1]
\n
d.iii.
\n
\n

Another student at the school, Jasmine, has a self-esteem value of 29.            

\n

By finding the equation of an appropriate regression line, estimate the time Jasmine spent on social media the previous day.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

Stratified sampling          A1

\n

[1 mark]

\n
a.
\n
\n

There are 260 students in total         A1

\n

\n\n\n84\n\n\n260\n\n\n×\n9\n=\n2.91\n         M1A1

\n

So 3 students will be selected.         AG

\n

[3 marks]

\n
b.i.
\n
\n

grade 9 \n=\n\n\n60\n\n\n260\n\n\n×\n9\n\n2\n,  grade 10 \n=\n\n\n83\n\n\n260\n\n\n×\n9\n\n3\n,  grade 11 \n=\n\n\n33\n\n\n260\n\n\n×\n9\n\n1\n         A2

\n

[2 marks]

\n
b.ii.
\n
\n

Systematic sampling        A1

\n

[1 mark]

\n
c.
\n
\n

\nr\n=\n\n0.901\n       A2

\n

[2 marks]

\n
d.i.
\n
\n

The negative value of \nr\n indicates that more time spent on social media leads to lower self-esteem, supporting the principal’s concerns.      R1

\n

[1 mark]

\n
d.ii.
\n
\n

\nr\n being close to –1 indicates there is strong correlation, so a regression line is appropriate.      R1

\n

[1 mark]

\n
d.iii.
\n
\n

Find the regression line of \nt\n on \ns\n.       M1

\n

\nt\n=\n\n0.281\ns\n+\n9.74\n        A1

\n

\nt\n=\n\n(\n\n\n0.2807\n\n\n)\n\n\n(\n\n29\n\n)\n\n+\n9.739\n\n=\n1.60\n hours       M1A1

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
d.iii.
\n
\n[N/A]\n
e.
\n
", "question_id": "EXM.2.SL.TZ0.1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

In this question give all answers correct to two decimal places.

\n

Javier takes 5000 US dollars (USD) on a business trip to Venezuela. He exchanges 3000 USD into Venezuelan bolívars (VEF).

\n

The exchange rate is 1 USD \n=\n 6.3021 VEF.

\n
\n

During his time in Venezuela, Javier spends 1250 USD and 12 000 VEF. On his return home, Javier exchanges his remaining VEF into USD.

\n

The exchange rate is 1 USD \n=\n 8.7268 VEF.

\n
\n

Calculate the amount of VEF that Javier receives.

\n
[2]
\n
a.
\n
\n

Calculate the total amount, in USD, that Javier has remaining from his 5000 USD after his trip to Venezuela.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

The first answer not given correct to two decimal places is not awarded the final (A1).

\n

Incorrect rounding is not penalized thereafter.

\n

\n3000\n×\n6.3021\n    (M1)

\n

 

\n

Note:     Award (M1) for multiplying 3000 by 6.3021.

\n

 

\n

\n=\n18906.30\n     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

\n\n\n18906.30\n\n12000\n\n\n8.7268\n\n\n\n + \n\n(\n2000\n\n1250\n)\n    (M1)(M1)(M1)

\n

 

\n

Note:     Award (M1) for subtracting 12 000 from their answer to part (a) OR for 6906.30 seen, (M1) for dividing their amount by 8.7268 (can be implied if 791.389… seen) and (M1) for \n2000\n\n1250\n OR 750 seen.

\n

 

\n

\n=\n1541.39\n    (A1)(ft)     (C4)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_4", "topics": [], "subtopics": [] }, { "Question": "
\n

A water container is made in the shape of a cylinder with internal height \nh\n cm and internal base radius \nr\n cm.

\n

\"N16/5/MATSD/SP2/ENG/TZ0/06\"

\n

The water container has no top. The inner surfaces of the container are to be coated with a water-resistant material.

\n
\n

The volume of the water container is \n0.5\n\n \n\n\n\n\nm\n\n3\n\n\n.

\n
\n

The water container is designed so that the area to be coated is minimized.

\n
\n

One can of water-resistant material coats a surface area of \n2000\n\n c\n\n\n\n\nm\n\n2\n\n\n.

\n
\n

Write down a formula for A , the surface area to be coated.

\n
[2]
\n
a.
\n
\n

Express this volume in  c m 3 .

\n
[1]
\n
b.
\n
\n

Write down, in terms of r and h , an equation for the volume of this water container.

\n
[1]
\n
c.
\n
\n

Show that A = π r 2 + 1 000 000 r .

\n
[2]
\n
d.
\n
\n

Find d A d r .

\n
[3]
\n
e.
\n
\n

Using your answer to part (e), find the value of r which minimizes A .

\n
[3]
\n
f.
\n
\n

Find the value of this minimum area.

\n
[2]
\n
g.
\n
\n

Find the least number of cans of water-resistant material that will coat the area in part (g).

\n
[3]
\n
h.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

( A = )   π r 2 + 2 π r h    (A1)(A1)

\n

 

\n

Note:     Award (A1) for either π r 2  OR 2 π r h seen. Award (A1) for two correct terms added together.

\n

 

\n

[2 marks]

\n
a.
\n
\n

500 000    (A1)

\n

 

\n

Notes:     Units not required.

\n

 

\n

[1 mark]

\n
b.
\n
\n

500 000 = π r 2 h    (A1)(ft)

\n

 

\n

Notes:     Award (A1)(ft) for π r 2 h equating to their part (b).

\n

Do not accept unless V = π r 2 h is explicitly defined as their part (b).

\n

 

\n

[1 mark]

\n
c.
\n
\n

A = π r 2 + 2 π r ( 500 000 π r 2 )    (A1)(ft)(M1)

\n

 

\n

Note:     Award (A1)(ft) for their 500 000 π r 2 seen.

\n

Award (M1) for correctly substituting only 500 000 π r 2 into a correct part (a).

\n

Award (A1)(ft)(M1) for rearranging part (c) to π r h = 500 000 r and substituting for π r h  in expression for A .

\n

 

\n

A = π r 2 + 1 000 000 r    (AG)

\n

 

\n

Notes:     The conclusion, A = π r 2 + 1 000 000 r , must be consistent with their working seen for the (A1) to be awarded.

\n

Accept 10 6 as equivalent to 1 000 000 .

\n

 

\n

[2 marks]

\n
d.
\n
\n

2 π r 1 000 000 r 2    (A1)(A1)(A1)

\n

 

\n

Note:     Award (A1) for 2 π r , (A1) for 1 r 2 or r 2 , (A1) for 1 000 000 .

\n

 

\n

[3 marks]

\n
e.
\n
\n

2 π r 1 000 000 r 2 = 0    (M1)

\n

 

\n

Note:     Award (M1) for equating their part (e) to zero.

\n

 

\n

r 3 = 1 000 000 2 π OR  r = 1 000 000 2 π 3     (M1)

\n

 

\n

Note:     Award (M1) for isolating r .

\n

 

\n

OR

\n

sketch of derivative function     (M1)

\n

with its zero indicated     (M1)

\n

( r = )   54.2   ( cm )   ( 54.1926 )    (A1)(ft)(G2)

\n

[3 marks]

\n
f.
\n
\n

π ( 54.1926 ) 2 + 1 000 000 ( 54.1926 )    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution of their part (f) into the given equation.

\n

 

\n

= 27 700   ( c m 2 )   ( 27 679.0 )    (A1)(ft)(G2)

\n

[2 marks]

\n
g.
\n
\n

27 679.0 2000    (M1)

\n

 

\n

Note:     Award (M1) for dividing their part (g) by 2000.

\n

 

\n

= 13.8395    (A1)(ft)

\n

 

\n

Notes:     Follow through from part (g).

\n

 

\n

14 (cans)     (A1)(ft)(G3)

\n

 

\n

Notes:     Final (A1) awarded for rounding up their 13.8395 to the next integer.

\n

 

\n

[3 marks]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
", "question_id": "16N.2.SL.TZ0.T_6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

A random variable \nX\n is normally distributed with mean \nμ\n and standard deviation \nσ\n, such that \n\nP\n\n(\nX\n<\n30.31\n)\n=\n0.1180\n and \n\nP\n\n(\nX\n>\n42.52\n)\n=\n0.3060\n.

\n
\n

Find \nμ\n and \nσ\n.

\n
[6]
\n
a.
\n
\n

Find \n\nP\n\n\n(\n\n\n|\n\nX\n\nμ\n\n|\n\n<\n1.2\nσ\n\n)\n\n.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nP\n\n(\nX\n<\n42.52\n)\n=\n0.6940\n    (M1)

\n

either \n\nP\n\n\n(\n\nZ\n<\n\n\n30.31\n\nμ\n\nσ\n\n\n)\n\n=\n0.1180\n\n or P\n\n\n(\n\nZ\n<\n\n\n42.52\n\nμ\n\nσ\n\n\n)\n\n=\n0.6940\n     (M1)

\n

\n\n\n30.31\n\nμ\n\nσ\n\n=\n\n\n\n\n\n\nΦ\n\n\n1\n\n\n\n(\n0.1180\n)\n\n\n\n\n\n\n1.1850\n\n\n\n    (A1)

\n

\n\n\n42.52\n\nμ\n\nσ\n\n=\n\n\n\n\n\n\nΦ\n\n\n1\n\n\n\n(\n0.6940\n)\n\n\n\n\n\n0.5072\n\n\n\n    (A1)

\n

attempting to solve simultaneously     (M1)

\n

\nμ\n=\n38.9\n and \nσ\n=\n7.22\n     A1

\n

[6 marks]

\n
a.
\n
\n

\n\nP\n\n(\nμ\n\n1.2\nσ\n<\nX\n<\nμ\n+\n1.2\nσ\n)\n (or equivalent eg. \n2\n\nP\n\n(\nμ\n<\nX\n<\nμ\n+\n1.2\nσ\n)\n)     (M1)

\n

\n=\n0.770\n    A1

\n

 

\n

Note: Award (M1)A1 for \n\nP\n\n(\n\n1.2\n<\nZ\n<\n1.2\n)\n=\n0.770\n.

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.2.AHL.TZ0.H_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

In this question, give all answers to two decimal places.

\n

Velina travels from New York to Copenhagen with 1200 US dollars (USD). She exchanges her money to Danish kroner (DKK). The exchange rate is 1 USD = 7.0208 DKK.

\n
\n

At the end of her trip Velina has 3450 DKK left that she exchanges to USD. The bank charges a 5 % commission. The exchange rate is still 1 USD = 7.0208 DKK .

\n
\n

Calculate the amount that Velina receives in DKK.

\n
[2]
\n
a.
\n
\n

Calculate the amount, in DKK, that will be left to exchange after commission.

\n
[2]
\n
b.i.
\n
\n

Hence, calculate the amount of USD she receives.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

1200 × 7.0208       (M1)

\n

Note: Award (M1) for multiplying by 7.0208.

\n

8424.96 (DKK)       (A1) (C2)

\n

[2 marks] 

\n
a.
\n
\n

0.95 × 3450       (M1)

\n

Note: Award (M1) for multiplying 3450 by 0.95 (or equivalent).

\n

3277.50 (DKK)       (A1) (C2)

\n

Note: The answer must be given to two decimal places unless already penalized in part (a).

\n

[2 marks] 

\n
b.i.
\n
\n

\n\n\n3277.50\n\n\n7.0208\n\n\n      (M1)

\n

Note: Follow through from part (b)(i). Award (M1) for dividing their part (b)(i) by 7.0208.

\n

466.83 (USD)       (A1)(ft) (C2)

\n

Note: The answer must be given to two decimal places unless already penalized in parts (a) or (b)(i).

\n

[2 marks] 

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "19M.1.SL.TZ2.T_3", "topics": [], "subtopics": [] }, { "Question": "
\n

Phil takes out a bank loan of $150 000 to buy a house, at an annual interest rate of 3.5%. The interest is calculated at the end of each year and added to the amount outstanding.

\n
\n

To pay off the loan, Phil makes annual deposits of $P at the end of every year in a savings account, paying an annual interest rate of 2% . He makes his first deposit at the end of the first year after taking out the loan.

\n
\n

David visits a different bank and makes a single deposit of $Q , the annual interest rate being 2.8%.

\n
\n

Find the amount Phil would owe the bank after 20 years. Give your answer to the nearest dollar.

\n
[3]
\n
a.
\n
\n

Show that the total value of Phil’s savings after 20 years is ( 1.02 20 1 ) P ( 1.02 1 ) .

\n
[3]
\n
b.
\n
\n

Given that Phil’s aim is to own the house after 20 years, find the value for P  to the nearest dollar.

\n
[3]
\n
c.
\n
\n

David wishes to withdraw $5000 at the end of each year for a period of n years. Show that an expression for the minimum value of Q is

\n

5000 1.028 + 5000 1.028 2 + + 5000 1.028 n .

\n
[3]
\n
d.i.
\n
\n

Hence or otherwise, find the minimum value of Q that would permit David to withdraw annual amounts of $5000 indefinitely. Give your answer to the nearest dollar.

\n
[3]
\n
d.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

150000 × 1.035 20     (M1)(A1)

\n

= $ 298468     A1

\n

 

\n

Note:     Only accept answers to the nearest dollar. Accept $298469.

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to look for a pattern by considering 1 year, 2 years etc     (M1)

\n

recognising a geometric series with first term P and common ratio 1.02     (M1)

\n

EITHER

\n

P + 1.02 P + + 1.02 19 P   ( = P ( 1 + 1.02 + + 1.02 19 ) )     A1

\n

OR

\n

explicitly identify u 1 = P ,   r = 1.02 and n = 20 (may be seen as S 20 ).     A1

\n

THEN

\n

s 20 = ( 1.02 20 1 ) P ( 1.02 1 )     AG

\n

[3 marks]

\n
b.
\n
\n

24.297 P = 298468     (M1)(A1)

\n

P = 12284     A1

\n

 

\n

Note:     Accept answers which round to 12284.

\n

 

\n

[3 marks]

\n
c.
\n
\n

METHOD 1

\n

Q ( 1.028 n ) = 5000 ( 1 + 1.028 + 1.028 2 + 1.028 3 + + 1.028 n 1 )     M1A1

\n

Q = 5000 ( 1 + 1.028 + 1.028 2 + 1.028 3 + . . . + 1.028 n 1 ) 1.028 n     A1

\n

= 5000 1.028 + 5000 1.028 2 + + 5000 1.028 n     AG

\n

 

\n

METHOD 2

\n

the initial value of the first withdrawal is 5000 1.028     A1

\n

the initial value of the second withdrawal is 5000 1.028 2     R1

\n

the investment required for these two withdrawals is 5000 1.028 + 5000 1.028 2     R1

\n

Q = 5000 1.028 + 5000 1.028 2 + + 5000 1.028 n     AG

\n

 

\n

[3 Marks]

\n
d.i.
\n
\n

sum to infinity is 5000 1.028 1 1 1.028     (M1)(A1)

\n

= 178571.428

\n

so minimum amount is $178572     A1

\n

 

\n

Note:     Accept answers which round to $178571 or $178572.

\n

 

\n

[3 Marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "17N.2.AHL.TZ0.H_12", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

It is given that one in five cups of coffee contain more than 120 mg of caffeine.
It is also known that three in five cups contain more than 110 mg of caffeine.

\n

Assume that the caffeine content of coffee is modelled by a normal distribution.
Find the mean and standard deviation of the caffeine content of coffee.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

let \nX\n be the random variable “amount of caffeine content in coffee”

\n

\n\nP\n\n(\nX\n>\n120\n)\n=\n0.2\n,\n\n P\n\n(\nX\n>\n110\n)\n=\n0.6\n     (M1)

\n

\n(\n\n\nP\n\n(\nX\n<\n120\n)\n=\n0.8\n,\n\n P\n\n(\nX\n<\n110\n)\n=\n0.4\n)\n

\n

 

\n

Note:     Award M1 for at least one correct probability statement.

\n

 

\n

\n\n\n120\n\nμ\n\nσ\n\n=\n0.84162\n\n,\n\n \n\n\n\n110\n\nμ\n\nσ\n\n=\n\n0.253347\n\n     (M1)(A1)(A1)

\n

 

\n

Note:     Award M1 for attempt to find at least one appropriate \nz\n-value.

\n

 

\n

\n120\n\nμ\n=\n0.84162\nσ\n,\n\n \n\n110\n\nμ\n=\n\n0.253347\nσ\n

\n

attempt to solve simultaneous equations     (M1)

\n

\nμ\n=\n112\n,\n\n \n\nσ\n=\n9.13\n     A1

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.2.AHL.TZ0.H_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Consider the curve defined by the equation \n4\n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n=\n7\n.

\n
\n

Find the volume of the solid formed when the region bounded by the curve, the x -axis for x 0 and the y -axis for y 0 is rotated through 2 π about the x -axis.

\n
", "Markscheme": "
\n

Use of V = π 0 7 2 y 2 d x

\n

V = π 0 7 2 ( 7 4 x 2 ) d x     (M1)(A1)

\n

 

\n

Note:     Condone absence of limits or incorrect limits for M mark.

\n

Do not condone absence of or multiples of π .

\n

 

\n

= 19.4 ( = 7 7 π 3 )      A1

\n

[3 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.AHL.TZ2.H_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-17-areas-under-curve-onto-y-axis-volume-of-revolution-(about-x-and-y-axes)" ] }, { "Question": "
\n

This question investigates some applications of differential equations to modeling population growth.

\n

One model for population growth is to assume that the rate of change of the population is proportional to the population, i.e. \n\n\n\nd\n\nP\n\n\n\nd\n\nt\n\n\n=\nk\nP\n, where \nk\n\n\nR\n\n, \nt\n is the time (in years) and \nP\n is the population

\n
\n

The initial population is 1000.

\n
\n

Given that \nk\n=\n0.003\n, use your answer from part (a) to find

\n
\n

Consider now the situation when \nk\n is not a constant, but a function of time.

\n
\n

Given that \nk\n=\n0.003\n+\n0.002\nt\n, find

\n
\n

Another model for population growth assumes

\n\n
\n

Show that the general solution of this differential equation is  P = A e k t , where A R .

\n
[5]
\n
a.
\n
\n

the population after 10 years

\n
[2]
\n
b.i.
\n
\n

the number of years it will take for the population to triple.

\n
[2]
\n
b.ii.
\n
\n

lim t P

\n
[1]
\n
b.iii.
\n
\n

the solution of the differential equation, giving your answer in the form P = f ( t ) .

\n
[5]
\n
c.i.
\n
\n

the number of years it will take for the population to triple.

\n
[4]
\n
c.ii.
\n
\n

Show that  d P d t = m L P ( L P ) , where m R .

\n
[2]
\n
d.
\n
\n

Solve the differential equation d P d t = m L P ( L P ) , giving your answer in the form P = g ( t ) .

\n
[10]
\n
e.
\n
\n

Given that the initial population is 1000, L = 10000   and m = 0.003 , find the number of years it will take for the population to triple.

\n
[4]
\n
f.
\n
", "Markscheme": "
\n

1 P d P = k d t         M1A1

\n

ln P = k t + c          A1A1

\n

P = e k t + c          A1

\n

P = A e k t , where  A = e c          AG

\n

[5 marks]

\n
a.
\n
\n

when  t = 0 , P = 1000

\n

A = 1000          A1

\n

P ( 10 ) = 1000 e 0.003 ( 10 ) = 1030          A1

\n

[2 marks]

\n
b.i.
\n
\n

3000 = 1000 e 0.003 t         M1

\n

t = ln 3 0.003 = 366 years        A1

\n

[2 marks]

\n
b.ii.
\n
\n

lim t P =        A1

\n

[1 mark]

\n
b.iii.
\n
\n

1 P d P = ( 0.003 + 0.002 t ) d t         M1

\n

ln P = 0.003 t + 0.001 t 2 + c         A1A1

\n

P = e 0.003 t + 0.001 t 2 + c         A1

\n

when  t = 0 , P = 1000

\n

e c = 1000         M1

\n

P = 1000 e 0.003 t + 0.001 t 2

\n

[5 marks]

\n
c.i.
\n
\n

3000 = 1000 e 0.003 t + 0.001 t 2         M1

\n

ln 3 = 0.003 t + 0.001 t 2         A1

\n

Use of quadratic formula or GDC graph or GDC polysmlt        M1

\n

t = 31.7 years         A1

\n

[4 marks]

\n
c.ii.
\n
\n

k = m ( 1 P L ) , where m  is the constant of proportionality        A1

\n

So d P d t = m ( 1 P L ) P         A1

\n

d P d t = m L P ( L P )         AG

\n

[2 marks]

\n
d.
\n
\n

1 P ( L P ) d P = m L d t         M1

\n

1 P ( L P ) = A P + B L P         M1

\n

1 A ( L P ) + B P         A1

\n

A = 1 L , B = 1 L         A1

\n

1 L ( 1 P + 1 L P ) d P = m L d t

\n

1 L ( ln P ln ( L P ) ) = m L t + c         A1A1

\n

ln ( P L P ) = m t + d , where  d = c L         M1

\n

P L P = C e m t , where  C = e d         A1

\n

P ( 1 + C e m t ) = C L e m t         M1

\n

P = C L e m t ( 1 + C e m t )   ( = L ( D e m t + 1 ) , where D = 1 C )         A1

\n

[10 marks]

\n
e.
\n
\n

1000 = 10000 D + 1         M1

\n

D = 9         A1

\n

3000 = 10000 9 e 0.003 t + 1         M1

\n

t = 450 years        A1

\n

[4 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "EXM.3.AHL.TZ0.4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-11-partial-fractions" ] }, { "Question": "
\n

The speed of light is \n\n300\n\n\n\n000\n\n kilometres per second. The average distance from the Sun to the Earth is 149.6 million km.

\n
\n

A light-year is the distance light travels in one year and is equal to \n\n9\n\n\n\n467\n\n\n\n280\n\n million km. Polaris is a bright star, visible from the Northern Hemisphere. The distance from the Earth to Polaris is 323 light-years.

\n
\n

Calculate the time, in minutes, it takes for light from the Sun to reach the Earth.

\n
[3]
\n
a.
\n
\n

Find the distance from the Earth to Polaris in millions of km. Give your answer in the form \na\n×\n\n\n10\nk\n\n\n with \n1\n\na\n<\n10\n and \nk\n\n\nZ\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n149600000\n\n\n300000\n×\n60\n\n\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for dividing the correct numerator (which can be presented in a different form such as \n149.6\n×\n\n\n10\n6\n\n\n or \n1.496\n×\n\n\n10\n8\n\n\n) by \n\n300\n\n\n\n000\n\n and (M1) for dividing by 60.

\n

 

\n

\n=\n8.31\n\n \n\n(\n\nminutes\n\n)\n\n \n\n(\n8.31111\n\n\n, 8 minutes 19 seconds\n\n)\n     (A1)     (C3)

\n

[3 marks]

\n
a.
\n
\n

\n323\n×\n9467\n\n280\n     (M1)

\n

 

\n

Note:     Award (M1) for multiplying 323 by \n9\n\n467\n\n280\n, seen with any power of 10; therefore only penalizing incorrect power of 10 once.

\n

 

\n

\n=\n3.06\n×\n\n\n10\n9\n\n\n\n ( = \n\n3.05793\n\n×\n\n\n10\n9\n\n\n)\n     (A1)(A1)     (C3)

\n

 

\n

Note:     Award (A1) for 3.06.

\n

Award (A1) for \n×\n\n\n10\n9\n\n\n

\n

Award (A0)(A0) for answers of the type: \n30.6\n×\n\n\n10\n8\n\n\n

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.SL.TZ0.T_3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-1-using-standard-form" ] }, { "Question": "
\n

An arithmetic sequence \n\n\nu\n1\n\n\n\n\n\n\n\nu\n2\n\n\n\n\n\n\n\nu\n3\n\n\n\n has \n\n\nu\n1\n\n\n=\n1\n and common difference \nd\n\n0\n. Given that \n\n\nu\n2\n\n\n\n\n\n\n\nu\n3\n\n\n and \n\n\nu\n6\n\n\n are the first three terms of a geometric sequence

\n
\n

Given that \n\n\nu\nN\n\n\n=\n\n15\n

\n
\n

find the value of \nd\n.

\n
[4]
\n
a.
\n
\n

determine the value of \n\n\n\nr\n=\n1\n\nN\n\n\n\n\nu\nr\n\n\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

use of \n\n\nu\nn\n\n\n=\n\n\nu\n1\n\n\n+\n(\nn\n\n1\n)\nd\n     M1

\n

\n\n(\n1\n+\n2\nd\n\n)\n2\n\n\n=\n(\n1\n+\nd\n)\n(\n1\n+\n5\nd\n)\n (or equivalent)     M1A1

\n

\nd\n=\n\n2\n     A1

\n

[4 marks]

\n
a.
\n
\n

\n1\n+\n(\nN\n\n1\n)\n×\n\n2\n=\n\n15\n

\n

\nN\n=\n9\n     (A1)

\n

\n\n\n\nr\n=\n1\n\n9\n\n\n\n\nu\nr\n\n\n\n=\n\n9\n2\n\n(\n2\n+\n8\n×\n\n2\n)\n     (M1)

\n

\n=\n\n63\n     A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.AHL.TZ1.H_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

A health inspector analysed the amount of sugar in 500 different snacks prepared in various school cafeterias. The collected data are shown in the following box-and-whisker diagram.

\n


Amount of sugar per snack in grams

\n
\n

State what 13 represents in the given diagram.

\n
[1]
\n
a.
\n
\n

Write down the interquartile range for this data.

\n
[2]
\n
b.i.
\n
\n

Write down the approximate number of snacks whose amount of sugar ranges from 18 to 20 grams.

\n
[1]
\n
b.ii.
\n
\n

The health inspector visits two school cafeterias. She inspects the same number of meals at each cafeteria. The data is shown in the following box-and-whisker diagrams.

\n

\n

Meals prepared in the school cafeterias are required to have less than 10 grams of sugar.

\n

State, giving a reason, which school cafeteria has more meals that do not meet the requirement.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

median      (A1) (C1)  

\n

[1 mark]

\n
a.
\n
\n

18 − 12      (A1) 

\n

Note: Award (M1) for correct quartiles seen.

\n

6 (g)      (A1) (C2)

\n

[2 marks]

\n
b.i.
\n
\n

125      (A1) (C1)

\n

[1 mark]

\n
b.ii.
\n
\n

Cafeteria 2       (A1) (C1)

\n

75 % > 50 % (do not meet the requirement)        (R1) (C1)

\n

OR

\n

25 % < 50 % (meet the requirement)       (R1) (C1)

\n

Note: Do not award (A1)(R0). Award the (R1) for a correct comparison of percentages for both cafeterias, which may be in words. The percentage values or fractions must be seen. It is possible to award (A0)(R1).

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

A type of candy is packaged in a right circular cone that has volume \n\n100 c\n\n\n\n\nm\n\n\n3\n\n\n\n and vertical height 8 cm.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/09\"

\n
\n

Find the radius, \nr\n, of the circular base of the cone.

\n
[2]
\n
a.
\n
\n

Find the slant height, \nl\n, of the cone.

\n
[2]
\n
b.
\n
\n

Find the curved surface area of the cone.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n100\n=\n\n1\n3\n\nπ\n\n\nr\n2\n\n\n(\n8\n)\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into volume of cone formula.

\n

 

\n

\nr\n=\n3.45\n\n (cm) \n\n\n(\n\n3.45494\n\n\n (cm)\n\n\n)\n\n     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

\n\n\nl\n2\n\n\n=\n\n\n8\n2\n\n\n+\n\n(\n3.45494\n\n\n)\n2\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into Pythagoras’ theorem.

\n

 

\n

\nl\n=\n8.71\n\n (cm) \n\n\n(\n\n8.71416\n\n\n (cm)\n\n\n)\n\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[2 marks]

\n
b.
\n
\n

\nπ\n×\n3.45494\n\n×\n8.71416\n\n     (M1)

\n

 

\n

Note:     Award (M1) for their correct substitutions into curved surface area of a cone formula.

\n

 

\n

\n=\n94.6\n\n c\n\n\n\n\nm\n\n2\n\n\n\n \n\n(\n94.5836\n\n\n c\n\n\n\n\nm\n\n2\n\n\n)\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from parts (a) and (b). Accept \n94.4\n\n c\n\n\n\n\nm\n\n2\n\n\n from use of 3 sf values.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ1.T_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

A sample of 120 oranges was tested for Vitamin C content. The cumulative frequency curve below represents the Vitamin C content, in milligrams, of these oranges.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/02\"

\n
\n

The minimum level of Vitamin C content of an orange in the sample was 30.1 milligrams. The maximum level of Vitamin C content of an orange in the sample was 35.0 milligrams.

\n
\n

Giving your answer to one decimal place, write down the value of

\n

(i)     the median level of Vitamin C content of the oranges in the sample;

\n

(ii)     the lower quartile;

\n

(iii)     the upper quartile.

\n
[3]
\n
a.
\n
\n

Draw a box-and-whisker diagram on the grid below to represent the Vitamin C content, in milligrams, for this sample.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/02.b\"

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(i)     32.5     (A1)

\n

(ii)     31.9     (A1)

\n

(iii)     33.1     (A1)     (C3)

\n

 

\n

Note:     Answers must be given correct to 1 decimal place.

\n

 

\n

[3 marks]

\n
a.
\n
\n

\"N16/5/MATSD/SP1/ENG/TZ0/02.b/M\"

\n

Note:     Award (A1)(ft) for correct median, (A1)(ft) for correct quartiles and box, (A1) for correct end points of whiskers and straight whiskers.

\n

Award at most (A1)(A1)(A0) if a horizontal line goes right through the box or if the whiskers are not well aligned with the midpoint of the box.

\n

Follow through from part (a).

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

The 1st, 4th and 8th terms of an arithmetic sequence, with common difference \nd\n, \nd\n\n0\n, are the first three terms of a geometric sequence, with common ratio \nr\n. Given that the 1st term of both sequences is 9 find

\n
\n

the value of \nd\n;

\n
[4]
\n
a.
\n
\n

the value of \nr\n;

\n
[1]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

EITHER

\n

the first three terms of the geometric sequence are \n9\n, \n9\nr\n and \n9\n\n\nr\n2\n\n\n     (M1)

\n

\n9\n+\n3\nd\n=\n9\nr\n(\n\n3\n+\nd\n=\n3\nr\n)\n and \n9\n+\n7\nd\n=\n9\n\n\nr\n2\n\n\n     (A1)

\n

attempt to solve simultaneously     (M1)

\n

\n9\n+\n7\nd\n=\n9\n\n\n\n(\n\n\n\n3\n+\nd\n\n3\n\n\n)\n\n2\n\n\n

\n

OR

\n

the \n\n\n\n1\n\n\n\nst\n\n\n\n\n, \n\n\n\n4\n\n\n\nth\n\n\n\n\n and \n\n\n\n8\n\n\n\nth\n\n\n\n\n terms of the arithmetic sequence are

\n

\n9\n,\n\n \n\n9\n+\n3\nd\n,\n\n \n\n9\n+\n7\nd\n     (M1)

\n

\n\n\n9\n+\n7\nd\n\n\n9\n+\n3\nd\n\n\n=\n\n\n9\n+\n3\nd\n\n9\n\n     (A1)

\n

attempt to solve     (M1)

\n

THEN

\n

\nd\n=\n1\n     A1

\n

[4 marks]

\n
a.
\n
\n

\nr\n=\n\n4\n3\n\n     A1

\n

 

\n

Note:     Accept answers where a candidate obtains \nd\n by finding \nr\n first. The first two marks in either method for part (a) are awarded for the same ideas and the third mark is awarded for attempting to solve an equation in \nr\n.

\n

 

\n

[1 mark]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.AHL.TZ2.H_3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The following diagram shows triangle ABC, with AB = 6 and AC = 8.

\n

\n
\n

Given that \n\ncos\n\n\n\n\nA\n^\n\n\n=\n\n5\n6\n\n find the value of \n\nsin\n\n\n\n\nA\n^\n\n\n.

\n
[3]
\n
a.
\n
\n

Find the area of triangle ABC.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid approach using Pythagorean identity      (M1)

\n

\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nA\n+\n\n\n\n(\n\n\n5\n6\n\n\n)\n\n2\n\n\n=\n1\n (or equivalent)     (A1)

\n

\n\nsin\n\n\nA\n=\n\n\n\n11\n\n\n6\n\n      A1

\n

[3 marks]

\n
a.
\n
\n

\n\n1\n2\n\n×\n8\n×\n6\n×\n\n\n\n11\n\n\n6\n\n  (or equivalent)     (A1)

\n

area \n=\n4\n\n11\n\n      A1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.1.SL.TZ0.1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Each month the number of days of rain in Cardiff is recorded.
The following data was collected over a period of 10 months.

\n

11    13    8    11    8    7    8    14    x    15

\n

For these data the median number of days of rain per month is 10.

\n
\n

Find the value of x.

\n
[2]
\n
a.
\n
\n

Find the standard deviation

\n
[2]
\n
b.i.
\n
\n

Find the interquartile range.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nx\n+\n11\n\n2\n\n=\n10\n    (M1)

\n

Note: Award (M1) for correct substitution into median formula or for arranging all 9 values into ascending/descending order.

\n

\n\n(\n\nx\n=\n\n)\n\n\n\n9\n    (A1) (C2)

\n

[2 marks]

\n
a.
\n
\n

2.69 (2.69072…)    (A2)(ft)

\n

Note: Follow through from part (a).

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

13 − 8    (M1)
Note: Award (M1) for 13 and 8 seen.

\n

= 5    (A1)(ft) (C4)
Note: Follow through from part (a).

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18M.1.SL.TZ1.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

Little Green island originally had no turtles. After 55 turtles were introduced to the island, their population is modelled by

\n

\nN\n\n(\nt\n)\n\n=\na\n×\n\n\n2\n\n\nt\n\n\n\n+\n10\n\n,\n\n\n\n\nt\n\n0\n\n,\n\n

\n

where \na\n is a constant and \nt\n is the time in years since the turtles were introduced.

\n

 

\n
\n

Find the value of \na\n.

\n
[2]
\n
a.
\n
\n

Find the time, in years, for the population to decrease to 20 turtles.

\n
[2]
\n
b.
\n
\n

There is a number \nm\n beyond which the turtle population will not decrease.

\n

Find the value of \nm\n. Justify your answer.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n55\n=\na\n×\n\n\n2\n0\n\n\n+\n10\n   (M1)

\n

Note: Award (M1) for correct substitution of zero and 55 into the function.

\n

45      (A1)   (C2)  

\n

[2 marks]

\n
a.
\n
\n

\n45\n×\n\n\n2\n\n\nt\n\n\n\n+\n10\n\n20\n       (M1)

\n

Note: Award (M1) for comparing correct expression involving 20 and their 45. Accept an equation.

\n

\nt\n=\n2.17\n  (2.16992…)      (A1)(ft)   (C2)

\n

Note: Follow through from their part (a), but only if positive.
Answer must be in years; do not accept months for the final (A1).  

\n

[2 marks]

\n
b.
\n
\n

\nm\n=\n10       (A1)

\n

because as the number of years increases the number of turtles approaches 10      (R1)   (C2)

\n

Note: Award (R1) for a sketch with an asymptote at approximately \ny\n=\n10\n,
OR for table with values such as 10.003 and 10.001 for \nt\n=\n14\n and \nt\n=\n15\n, for example,
OR when \nt\n approaches large numbers \ny\n approaches 10. Do not award (A1)(R0). 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_13", "topics": [], "subtopics": [] }, { "Question": "
\n

The 3rd term of an arithmetic sequence is 1407 and the 10th term is 1183.

\n
\n

Calculate the number of positive terms in the sequence.

\n
", "Markscheme": "
\n

1471 + (n − 1)(−32) > 0      (M1)

\n

n < \n\n\n1471\n\n\n32\n\n\n+\n1\n

\n

n < 46.96…      (A1)

\n

so 46 positive terms      A1

\n

[3 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.AHL.TZ1.H_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

It is known that the number of fish in a given lake will decrease by 7% each year unless some new fish are added. At the end of each year, 250 new fish are added to the lake.

\n

At the start of 2018, there are 2500 fish in the lake.

\n
\n

Show that there will be approximately 2645 fish in the lake at the start of 2020.

\n
[3]
\n
a.
\n
\n

Find the approximate number of fish in the lake at the start of 2042.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

EITHER

\n

2019:  2500 × 0.93 + 250 = 2575       (M1)A1

\n

2020:  2575 × 0.93 + 250       M1

\n

OR

\n

2020:  2500 × 0.932 + 250(0.93 + 1)      M1M1A1

\n

Note: Award M1 for starting with 2500, M1 for multiplying by 0.93 and adding 250 twice. A1 for correct expression. Can be shown in recursive form.

\n

THEN

\n

(= 2644.75) = 2645       AG

\n

[3 marks]

\n
a.
\n
\n

2020:  2500 × 0.932 + 250(0.93 + 1)
2042:  2500 × 0.9324 + 250(0.9323 + 0.9322 + … + 1)      (M1)(A1)

\n

\n=\n2500\n×\n\n\n0.93\n\n24\n\n\n\n+\n250\n\n\n\n(\n\n\n\n\n0.93\n\n\n24\n\n\n\n\n1\n\n)\n\n\n\n\n(\n\n0.93\n\n1\n\n)\n\n\n\n      (M1)(A1)

\n

=3384     A1

\n

Note: If recursive formula used, award M1 for un = 0.93 un−1 and u0 or u1 seen (can be awarded if seen in part (a)). Then award M1A1 for attempt to find u24 or u25 respectively (different term if other than 2500 used) (M1A0 if incorrect term is being found) and A2 for correct answer.

\n

Note: Accept all answers that round to 3380.

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.AHL.TZ1.H_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Let A and B be events such that \n\nP\n\n\n(\nA\n)\n\n=\n0.5\n, \n\nP\n\n\n(\nB\n)\n\n=\n0.4\n and \n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n=\n0.6\n.

\n

Find \n\nP\n\n\n(\n\n\n\n\nA\n\n\n|\n\nB\n\n)\n\n.

\n
", "Markscheme": "
\n

attempt to substitute into \n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n=\n\nP\n\n\n(\nA\n)\n\n+\n\nP\n\n\n(\nB\n)\n\n\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n    (M1)

\n

Note: Accept use of Venn diagram or other valid method.

\n

\n0.6\n=\n0.5\n+\n0.4\n\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n    (A1)

\n

\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n=\n0.3\n (seen anywhere)     A1

\n

attempt to substitute into \n\nP\n\n\n(\n\n\n\n\nA\n\n\n|\n\nB\n\n)\n\n=\n\n\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n\n\n\nP\n\n\n(\nB\n)\n\n\n\n    (M1)

\n

\n=\n\n\n0.3\n\n\n0.4\n\n\n

\n

\n\nP\n\n\n(\n\n\n\n\nA\n\n\n|\n\nB\n\n)\n\n=\n0.75\n\n(\n\n=\n\n3\n4\n\n\n)\n\n    A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.1.SL.TZ0.2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Consider a geometric sequence with a first term of 4 and a fourth term of −2.916.

\n
\n

Find the common ratio of this sequence.

\n
[3]
\n
a.
\n
\n

Find the sum to infinity of this sequence.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nu\n4\n\n\n=\n\n\nu\n1\n\n\n\n\nr\n3\n\n\n\n\n2.916\n=\n4\n\n\nr\n3\n\n\n      (A1)

\n

solving, \nr\n=\n\n0.9\n      (M1)A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

S = 4 1 ( 9 )       (M1)

\n

= 40 19 ( = 2.11 )      A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.2.AHL.TZ0.H_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series", "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

Show that \n\n\n\n(\n\n2\nn\n\n1\n\n)\n\n2\n\n\n+\n\n\n\n(\n\n2\nn\n+\n1\n\n)\n\n2\n\n\n=\n8\n\n\nn\n2\n\n\n+\n2\n, where \nn\n\n\nZ\n\n.

\n
[2]
\n
a.
\n
\n

Hence, or otherwise, prove that the sum of the squares of any two consecutive odd integers is even.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

attempting to expand the LHS   (M1)

\n

LHS \n=\n\n(\n\n4\n\n\nn\n2\n\n\n\n4\nn\n+\n1\n\n)\n\n+\n\n(\n\n4\n\n\nn\n2\n\n\n+\n4\nn\n+\n1\n\n)\n\n     A1

\n

\n=\n8\n\n\nn\n2\n\n\n+\n2\n (= RHS)    AG

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

recognition that \n\n2\nn\n\n1\n\n and \n\n2\nn\n+\n1\n\n represent two consecutive odd integers (for \nn\n\n\nZ\n\n)      R1

\n

\n8\n\n\nn\n2\n\n\n+\n2\n=\n2\n\n(\n\n4\n\n\nn\n2\n\n\n+\n1\n\n)\n\n     A1

\n

valid reason eg divisible by 2 (2 is a factor)       R1

\n

so the sum of the squares of any two consecutive odd integers is even        AG

\n

 

\n

METHOD 2

\n

recognition, eg that \n\n\nn\n\n and \n\nn\n+\n2\n\n represent two consecutive odd integers (for \nn\n\n\nZ\n\n)       R1

\n

\n\n\nn\n2\n\n\n+\n\n\n\n(\n\nn\n+\n2\n\n)\n\n2\n\n\n=\n2\n\n(\n\n\n\nn\n2\n\n\n+\n2\nn\n+\n2\n\n)\n\n     A1

\n

valid reason eg divisible by 2 (2 is a factor)       R1

\n

so the sum of the squares of any two consecutive odd integers is even        AG

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.1.SL.TZ0.3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-6-simple-proof" ] }, { "Question": "
\n

Let \n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n8\nx\n\n\n\n2\n\n\nx\n2\n\n\n+\n1\n\n\n\n. Given that \nf\n\n(\n0\n)\n\n=\n5\n, find \nf\n\n(\nx\n)\n\n.

\n
", "Markscheme": "
\n

attempt to integrate     (M1)

\n

\nu\n=\n2\n\n\nx\n2\n\n\n+\n1\n\n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n4\nx\n

\n

\n\n\n\n\n8\nx\n\n\n\n2\n\n\nx\n2\n\n\n+\n1\n\n\n\n\n\nd\n\nx\n=\n\n\n\n2\n\n\nu\n\n\n\n\n\nd\n\nu\n      (A1)

\n

EITHER

\n

\n=\n4\n\nu\n\n\n(\n\n+\nC\n\n)\n\n      A1

\n

OR

\n

\n=\n4\n\n2\n\n\nx\n2\n\n\n+\n1\n\n\n(\n\n+\nC\n\n)\n\n      A1

\n

THEN

\n

correct substitution into their integrated function (must have C)       (M1)

\n

\n5\n=\n4\n+\nC\n\nC\n=\n1\n

\n

\nf\n\n(\nx\n)\n\n=\n4\n\n2\n\n\nx\n2\n\n\n+\n1\n\n+\n1\n      A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "SPM.1.SL.TZ0.4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

Consider the equation \n\n\nx\n5\n\n\n\n3\n\n\nx\n4\n\n\n+\nm\n\n\nx\n3\n\n\n+\nn\n\n\nx\n2\n\n\n+\np\nx\n+\nq\n=\n0\n, where \nm\n, \nn\n, \np\n, \nq\n\n\nR\n\n.

\n

The equation has three distinct real roots which can be written as \n\nlo\n\n\n\n\ng\n\n2\n\n\n\na\n, \n\nlo\n\n\n\n\ng\n\n2\n\n\n\nb\n and \n\nlo\n\n\n\n\ng\n\n2\n\n\n\nc\n.

\n

The equation also has two imaginary roots, one of which is \nd\n\ni\n\n where \nd\n\n\nR\n\n.

\n
\n

The values \na\n, \nb\n, and \nc\n are consecutive terms in a geometric sequence.

\n
\n

Show that a b c = 8 .

\n
[5]
\n
a.
\n
\n

Show that one of the real roots is equal to 1.

\n
[3]
\n
b.
\n
\n

Given that q = 8 d 2 , find the other two real roots.

\n
[9]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

recognition of the other root  = d i        (A1)

\n

lo g 2 a + lo g 2 b + lo g 2 c + d i d i = 3         M1A1

\n

Note: Award M1 for sum of the roots, A1 for 3. Award A0M1A0 for just  lo g 2 a + lo g 2 b + lo g 2 c = 3 .

\n

lo g 2 a b c = 3        (M1)

\n

a b c = 2 3        A1

\n

a b c = 8        AG

\n

[5 marks]

\n
a.
\n
\n

METHOD 1

\n

let the geometric series be  u 1 u 1 r u 1 r 2

\n

( u 1 r ) 3 = 8       M1

\n

u 1 r = 2        A1

\n

hence one of the roots is  lo g 2 2 = 1       R1

\n

 

\n

METHOD 2

\n

b a = c b

\n

b 2 = a c b 3 = a b c = 8       M1

\n

b = 2        A1

\n

hence one of the roots is  lo g 2 2 = 1       R1

\n

 

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

product of the roots is  r 1 × r 2 × 1 × d i × d i = 8 d 2        (M1)(A1)

\n

r 1 × r 2 = 8        A1

\n

sum of the roots is r 1 + r 2 + 1 + d i + d i = 3        (M1)(A1)

\n

r 1 + r 2 = 2        A1

\n

solving simultaneously       (M1)

\n

r 1 = 2 r 2 = 4        A1A1

\n

 

\n

METHOD 2

\n

product of the roots  lo g 2 a × lo g 2 b × lo g 2 c × d i × d i = 8 d 2        M1A1

\n

lo g 2 a × lo g 2 b × lo g 2 c = 8        A1

\n

EITHER

\n

a b c  can be written as  2 r 2 2 r        M1

\n

( lo g 2 2 r ) ( lo g 2 2 ) ( lo g 2 2 r ) = 8

\n

attempt to solve       M1

\n

( 1 lo g 2 r ) ( 1 + lo g 2 r ) = 8

\n

lo g 2 r = ± 3

\n

r = 1 8 , 8        A1A1

\n

OR

\n

a b c  can be written as  a 2 , 4 a       M1

\n

( lo g 2 a ) ( lo g 2 2 ) ( lo g 2 4 a ) = 8

\n

attempt to solve       M1

\n

a = 1 4 , 16        A1A1

\n

THEN

\n

a and  c are  1 4 , 16        (A1)

\n

roots are −2, 4       A1

\n

 

\n

[9 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.AHL.TZ1.H_11", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

In the month before their IB Diploma examinations, eight male students recorded the number of hours they spent on social media.

\n

For each student, the number of hours spent on social media (\nx\n) and the number of IB Diploma points obtained (\ny\n) are shown in the following table.

\n

\"N16/5/MATSD/SP2/ENG/TZ0/01\"

\n
\n

Use your graphic display calculator to find

\n
\n

Ten female students also recorded the number of hours they spent on social media in the month before their IB Diploma examinations. Each of these female students spent between 3 and 30 hours on social media.

\n

The equation of the regression line y on x for these ten female students is

\n

\ny\n=\n\n\n2\n3\n\nx\n+\n\n\n125\n\n3\n\n.\n

\n

An eleventh girl spent 34 hours on social media in the month before her IB Diploma examinations.

\n
\n

On graph paper, draw a scatter diagram for these data. Use a scale of 2 cm to represent 5 hours on the \nx\n-axis and 2 cm to represent 10 points on the \ny\n-axis.

\n
[4]
\n
a.
\n
\n

(i)     \n\n\n\nx\n¯\n\n\n\n, the mean number of hours spent on social media;

\n

(ii)     \n\n\n\ny\n¯\n\n\n\n, the mean number of IB Diploma points.

\n
[2]
\n
b.
\n
\n

Plot the point \n(\n\n\nx\n¯\n\n\n,\n\n \n\n\n\ny\n¯\n\n\n)\n on your scatter diagram and label this point M.

\n
[2]
\n
c.
\n
\n

Write down the value of \nr\n, the Pearson’s product–moment correlation coefficient, for these data.

\n
[2]
\n
d.
\n
\n

Write down the equation of the regression line \ny\n on \nx\n for these eight male students.

\n
[2]
\n
e.
\n
\n

Draw the regression line, from part (e), on your scatter diagram.

\n
[2]
\n
f.
\n
\n

Use the given equation of the regression line to estimate the number of IB Diploma points that this girl obtained.

\n
[2]
\n
g.
\n
\n

Write down a reason why this estimate is not reliable.

\n
[1]
\n
h.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"N16/5/MATSD/SP2/ENG/TZ0/01.a/M\"     (A4)

\n

 

\n

Notes:     Award (A1) for correct scale and labelled axes.

\n

Award (A3) for 7 or 8 points correctly plotted,

\n

(A2) for 5 or 6 points correctly plotted,

\n

(A1) for 3 or 4 points correctly plotted.

\n

Award at most (A0)(A3) if axes reversed.

\n

Accept \nx\n and \ny\n sufficient for labelling.

\n

If graph paper is not used, award (A0).

\n

If an inconsistent scale is used, award (A0). Candidates’ points should be read from this scale where possible and awarded accordingly.

\n

A scale which is too small to be meaningful (ie mm instead of cm) earns (A0) for plotted points.

\n

 

\n

[4 marks]

\n
a.
\n
\n

(i)     \n\n\nx\n¯\n\n\n=\n21\n     (A1)

\n

(ii)    \n\n\ny\n¯\n\n\n=\n31\n     (A1)

\n

[2 marks]

\n
b.
\n
\n

\n(\n\n\nx\n¯\n\n\n,\n\n \n\n\n\ny\n¯\n\n\n)\n correctly plotted on graph     (A1)(ft)

\n

this point labelled M     (A1)

\n

 

\n

Note:     Follow through from parts (b)(i) and (b)(ii).

\n

Only accept M for labelling.

\n

 

\n

[2 marks]

\n
c.
\n
\n

\n\n0.973\n\n \n\n(\n\n0.973388\n\n)\n    (G2)

\n

 

\n

Note:     Award (G1) for 0.973, without minus sign.

\n

 

\n

[2 marks]

\n
d.
\n
\n

\ny\n=\n\n0.761\nx\n+\n47.0\n\n \n\n(\ny\n=\n\n0.760638\n\nx\n+\n46.9734\n\n)\n    (A1)(A1)(G2)

\n

 

\n

Notes:     Award (A1) for \n\n0.761\nx\n and (A1) \n+\n47.0\n. Award a maximum of (A1)(A0) if answer is not an equation.

\n

 

\n

[2 marks]

\n
e.
\n
\n

line on graph     (A1)(ft)(A1)(ft)

\n

 

\n

Notes:     Award (A1)(ft) for straight line that passes through their M, (A1)(ft) for line (extrapolated if necessary) that passes through \n(\n0\n,\n\n \n\n47.0\n)\n.

\n

If M is not plotted or labelled, follow through from part (e).

\n

 

\n

[2 marks]

\n
f.
\n
\n

\ny\n=\n\n\n2\n3\n\n(\n34\n)\n+\n\n\n125\n\n3\n\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution.

\n

 

\n

19 (points)     (A1)(G2)

\n

[2 marks]

\n
g.
\n
\n

extrapolation     (R1)

\n

OR

\n

34 hours is outside the given range of data     (R1)

\n

 

\n

Note:     Do not accept ‘outlier’.

\n

 

\n

[1 mark]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
", "question_id": "16N.2.SL.TZ0.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

A factory packages coconut water in cone-shaped containers with a base radius of 5.2 cm and a height of 13 cm.

\n
\n

The factory designers are currently investigating whether a cone-shaped container can be replaced with a cylinder-shaped container with the same radius and the same total surface area.

\n
\n

Find the volume of one cone-shaped container.

\n
[2]
\n
a.
\n
\n

Find the slant height of the cone-shaped container.

\n
[2]
\n
b.
\n
\n

Show that the total surface area of the cone-shaped container is 314 cm2, correct to three significant figures.

\n
[3]
\n
c.
\n
\n

Find the height, \nh\n, of this cylinder-shaped container.

\n
[4]
\n
d.
\n
\n

The factory director wants to increase the volume of coconut water sold per container.

\n

State whether or not they should replace the cone-shaped containers with cylinder‑shaped containers. Justify your conclusion.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nπ\n\n\n\n\n(\n\n5.2\n\n)\n\n\n2\n\n\n×\n13\n\n3\n\n    (M1)

\n

Note: Award (M1) for correct substitution in the volume formula for cone.

\n

368  (368.110…) cm3     (A1)(G2)

\n

Note: Accept 117.173…\nπ\n cm3 or \n\n\n8788\n\n\n75\n\n\nπ\n cm3.

\n

[2 marks]

\n
a.
\n
\n

(slant height2) = (5.2)2 + 132   (M1)

\n

Note: Award (M1) for correct substitution into the formula.

\n

14.0  (14.0014…) (cm)     (A1)(G2)

\n

[2 marks]

\n
b.
\n
\n

14.0014… × (5.2) × \nπ\n + (5.2)2 × \nπ\n     (M1)(M1)

\n

Note: Award (M1) for their correct substitution in the curved surface area formula for cone; (M1) for adding the correct area of the base. The addition must be explicitly seen for the second (M1) to be awarded. Do not accept rounded values here as may come from working backwards.

\n

313.679… (cm2)     (A1)

\n

Note: Use of 3 sf value 14.0 gives an unrounded answer of 313.656….

\n

314 (cm2)     (AG)

\n

Note: Both the unrounded and rounded answers must be seen for the final (A1) to be awarded.

\n

[3 marks]

\n
c.
\n
\n

2 × \nπ\n × (5.2) × \nh\n + 2 × \nπ\n × (5.2)2 = 314     (M1)(M1)(M1)

\n

Note: Award (M1) for correct substitution in the curved surface area formula for cylinder; (M1) for adding two correct base areas of the cylinder; (M1) for equating their total cylinder surface area to 314 (313.679…). For this mark to be awarded the areas of the two bases must be added to the cylinder curved surface area and equated to 314. Award at most (M1)(M0)(M0) for cylinder curved surface area equated to 314.

\n

(\nh\n =) 4.41 (4.41051…) (cm)     (A1)(G3)

\n

[4 marks]

\n
d.
\n
\n

\nπ\n × (5.2)2 × 4.41051…     (M1)

\n

Note: Award (M1) for correct substitution in the volume formula for cylinder.

\n

375  (374.666…) (cm3)     (A1)(ft)(G2)

\n

Note: Follow through from part (d).

\n

375 (cm3) > 368 (cm3)      (R1)(ft)

\n

OR

\n

“volume of cylinder is larger than volume of cone” or similar    (R1)(ft)

\n

Note: Follow through from their answer to part (a). The verbal statement should be consistent with their answers from parts (e) and (a) for the (R1) to be awarded.

\n

replace with the cylinder containers     (A1)(ft)

\n

Note: Do not award (A1)(ft)(R0). Follow through from their incorrect volume for the cylinder in this question part but only if substitution in the volume formula shown.

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "19M.2.SL.TZ2.T_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

The functions \nf\n and \ng\n are defined such that \nf\n\n(\nx\n)\n\n=\n\n\nx\n+\n3\n\n4\n\n and \ng\n\n(\nx\n)\n\n=\n8\nx\n+\n5\n.

\n
\n

Show that \n\n(\n\ng\n\nf\n\n)\n\n\n(\nx\n)\n\n=\n2\nx\n+\n11\n.

\n
[2]
\n
a.
\n
\n

Given that \n\n\n\n(\n\ng\n\nf\n\n)\n\n\n\n1\n\n\n\n\n(\na\n)\n\n=\n4\n, find the value of \na\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

attempt to form composition       M1

\n

correct substitution \ng\n\n(\n\n\n\nx\n+\n3\n\n4\n\n\n)\n\n=\n8\n\n(\n\n\n\nx\n+\n3\n\n4\n\n\n)\n\n+\n5\n    A1

\n

\n\n(\n\ng\n\nf\n\n)\n\n\n(\nx\n)\n\n=\n2\nx\n+\n11\n     AG

\n

[2 marks]

\n
a.
\n
\n

attempt to substitute 4 (seen anywhere)     (M1)

\n

correct equation \na\n=\n2\n×\n4\n+\n11\n      (A1)

\n

\na\n = 19     A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.1.SL.TZ0.5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

Given that \n\n\nlog\n\n10\n\n\n\n\n(\n\n\n1\n\n2\n\n2\n\n\n\n\n(\n\np\n+\n2\nq\n\n)\n\n\n)\n\n=\n\n1\n2\n\n\n(\n\n\n\n\nlog\n\n\n10\n\n\n\np\n+\n\n\n\nlog\n\n\n10\n\n\n\nq\n\n)\n\n,\n\n \n\np\n>\n0\n,\n\n \n\nq\n>\n0\n, find \np\n in terms of \nq\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nlog\n\n10\n\n\n\n\n1\n\n2\n\n2\n\n\n\n(\np\n+\n2\nq\n)\n=\n\n1\n2\n\n(\n\n\nlog\n\n10\n\n\n\np\n+\n\n\nlog\n\n10\n\n\n\nq\n)\n

\n

\n\n\nlog\n\n10\n\n\n\n\n1\n\n2\n\n2\n\n\n\n(\np\n+\n2\nq\n)\n=\n\n1\n2\n\n\n\nlog\n\n10\n\n\n\np\nq\n     (M1)

\n

\n\n\nlog\n\n10\n\n\n\n\n1\n\n2\n\n2\n\n\n\n(\np\n+\n2\nq\n)\n=\n\n\nlog\n\n10\n\n\n\n\n(\np\nq\n\n)\n\n\n1\n2\n\n\n\n\n     (M1)

\n

\n\n1\n\n2\n\n2\n\n\n\n(\np\n+\n2\nq\n)\n=\n\n(\np\nq\n\n)\n\n\n1\n2\n\n\n\n\n     (A1)

\n

\n\n(\np\n+\n2\nq\n\n)\n2\n\n\n=\n8\np\nq\n

\n

\n\n\np\n2\n\n\n+\n4\np\nq\n+\n4\n\n\nq\n2\n\n\n=\n8\np\nq\n

\n

\n\n\np\n2\n\n\n\n4\np\nq\n+\n4\n\n\nq\n2\n\n\n=\n0\n

\n

\n\n(\np\n\n2\nq\n\n)\n2\n\n\n=\n0\n     M1

\n

hence \np\n=\n2\nq\n     A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.AHL.TZ2.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

Show that \n\nlo\n\n\n\n\ng\n\n9\n\n\n\n(\n\n\ncos\n\n\n2\nx\n+\n2\n\n)\n\n=\n\nlo\n\n\n\n\ng\n\n3\n\n\n\n\ncos\n\n\n2\nx\n+\n2\n\n.

\n
[3]
\n
a.
\n
\n

Hence or otherwise solve \n\nlo\n\n\n\n\ng\n\n3\n\n\n\n(\n\n\n2\n\n\n\nsin\n\n\nx\n\n)\n\n=\n\nlo\n\n\n\n\ng\n\n9\n\n\n\n(\n\n\ncos\n\n\n2\nx\n+\n2\n\n)\n\n for \n0\n<\nx\n<\n\nπ\n2\n\n.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

attempting to use the change of base rule       M1

\n

\n\nlo\n\n\n\n\ng\n\n9\n\n\n\n(\n\n\ncos\n\n\n2\nx\n+\n2\n\n)\n\n=\n\n\n\nlo\n\n\n\n\ng\n\n3\n\n\n\n(\n\n\ncos\n\n\n2\nx\n+\n2\n\n)\n\n\n\n\nlo\n\n\n\n\ng\n\n3\n\n\n9\n\n\n       A1

\n

\n=\n\n1\n2\n\n\nlo\n\n\n\n\ng\n\n3\n\n\n\n(\n\n\ncos\n\n\n2\nx\n+\n2\n\n)\n\n       A1

\n

\n=\n\nlo\n\n\n\n\ng\n\n3\n\n\n\n\ncos\n\n\n2\nx\n+\n2\n\n     AG

\n

[3 marks]

\n
a.
\n
\n

\n\nlo\n\n\n\n\ng\n\n3\n\n\n\n(\n\n\n2\n\n\n\nsin\n\n\nx\n\n)\n\n=\n\nlo\n\n\n\n\ng\n\n3\n\n\n\n\ncos\n\n\n2\nx\n+\n2\n\n

\n

\n\n2\n\n\n\nsin\n\n\nx\n=\n\n\ncos\n\n\n2\nx\n+\n2\n\n      M1

\n

\n\n4\n\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nx\n=\n\ncos\n\n\n2\nx\n+\n2\n (or equivalent)      A1

\n

use of \n\ncos\n\n\n2\nx\n=\n1\n\n2\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nx\n      (M1)

\n

\n6\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nx\n=\n3\n

\n

\n\nsin\n\n\nx\n=\n\n(\n±\n)\n\n\n1\n\n\n2\n\n\n\n      A1

\n

\nx\n=\n\nπ\n4\n\n      A1

\n

Note: Award A0 if solutions other than \nx\n=\n\nπ\n4\n\n are included.

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "SPM.1.SL.TZ0.6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-6-pythagorean-identity-double-angles" ] }, { "Question": "
\n

Show that \n\nlo\n\n\n\n\ng\n\n\n\n\nr\n2\n\n\n\n\n\nx\n=\n\n1\n2\n\n\nlo\n\n\n\n\ng\n\nr\n\n\n\nx\n where \nr\n,\n\nx\n\n\n\n\nR\n\n+\n\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\nlo\n\n\n\n\ng\n\n\n\n\nr\n2\n\n\n\n\n\nx\n=\n\n\n\nlo\n\n\n\n\ng\n\nr\n\n\n\nx\n\n\n\nlo\n\n\n\n\ng\n\nr\n\n\n\n\n\nr\n2\n\n\n\n\n\n(\n\n=\n\n\n\nlo\n\n\n\n\ng\n\nr\n\n\n\nx\n\n\n\n2\n\n\n\nlo\n\n\n\n\ng\n\nr\n\n\n\nr\n\n\n\n)\n\n     M1A1

\n

\n=\n\n\n\nlo\n\n\n\n\ng\n\nr\n\n\n\nx\n\n2\n\n     AG

\n

[2 marks]

\n

 

\n

METHOD 2

\n

\n\nlo\n\n\n\n\ng\n\n\n\n\nr\n2\n\n\n\n\n\nx\n=\n\n1\n\n\nlo\n\n\n\n\ng\n\nx\n\n\n\n\n\nr\n2\n\n\n\n\n     M1

\n

\n=\n\n1\n\n2\n\n\nlo\n\n\n\n\ng\n\nx\n\n\n\nr\n\n\n     A1

\n

\n=\n\n\n\nlo\n\n\n\n\ng\n\nr\n\n\n\nx\n\n2\n\n     AG

\n

[2 marks]

\n

 

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ2.H_11", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

Solve the simultaneous equations

\n

\n\nlo\n\n\n\n\ng\n\n2\n\n\n6\nx\n=\n1\n+\n2\n\n\nlo\n\n\n\n\ng\n\n2\n\n\ny\n

\n

\n1\n+\n\nlo\n\n\n\n\ng\n\n6\n\n\nx\n=\n\nlo\n\n\n\n\ng\n\n6\n\n\n\n(\n\n15\ny\n\n25\n\n)\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

use of at least one “log rule” applied correctly for the first equation       M1

\n

\n\nlo\n\n\n\n\ng\n\n2\n\n\n6\nx\n=\n\nlo\n\n\n\n\ng\n\n2\n\n\n2\n+\n2\n\n\nlo\n\n\n\n\ng\n\n2\n\n\ny\n

\n

\n=\n\nlo\n\n\n\n\ng\n\n2\n\n\n2\n+\n\n\nlo\n\n\n\n\ng\n\n2\n\n\n\n\ny\n2\n\n\n

\n

\n=\n\nlo\n\n\n\n\ng\n\n2\n\n\n\n(\n\n2\n\n\ny\n2\n\n\n\n)\n\n

\n

\n\n6\nx\n=\n2\n\n\ny\n2\n\n\n       A1

\n

use of at least one “log rule” applied correctly for the second equation       M1

\n

\n\nlo\n\n\n\n\ng\n\n6\n\n\n\n(\n\n15\ny\n\n25\n\n)\n\n=\n1\n+\n\nlo\n\n\n\n\ng\n\n6\n\n\nx\n

\n

\n=\n\nlo\n\n\n\n\ng\n\n6\n\n\n6\n+\n\nlo\n\n\n\n\ng\n\n6\n\n\nx\n

\n

\n=\n\nlo\n\n\n\n\ng\n\n6\n\n\n6\nx\n

\n

\n\n15\ny\n\n25\n=\n6\nx\n       A1

\n

attempt to eliminate \nx\n (or \ny\n) from their two equations       M1

\n

\n2\n\n\ny\n2\n\n\n=\n15\ny\n\n25\n

\n

\n2\n\n\ny\n2\n\n\n\n15\ny\n+\n25\n=\n0\n

\n

\n\n(\n\n2\ny\n\n5\n\n)\n\n\n(\n\ny\n\n5\n\n)\n\n=\n0\n

\n

\nx\n=\n\n\n25\n\n\n12\n\n\n\n,\n\n\n\ny\n=\n\n5\n2\n\n\n,\n\n       A1

\n

or \nx\n=\n\n\n25\n\n3\n\n\n,\n\n\n\ny\n=\n5\n       A1

\n

Note: \nx\n, \ny\n values do not have to be “paired” to gain either of the final two A marks.

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ2.H_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

A solid glass paperweight consists of a hemisphere of diameter 6 cm on top of a cuboid with a square base of length 6 cm, as shown in the diagram.

\n

\n

The height of the cuboid, x cm, is equal to the height of the hemisphere.

\n
\n

Write down the value of x.

\n
[1]
\n
a.i.
\n
\n

Calculate the volume of the paperweight.

\n
[3]
\n
a.ii.
\n
\n

1 cm3 of glass has a mass of 2.56 grams.

\n

Calculate the mass, in grams, of the paperweight.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

3 (cm)    (A1) (C1)

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

units are required in part (a)(ii)

\n

 

\n

\n\n1\n2\n\n×\n\n\n4\nπ\n×\n\n\n\n\n(\n3\n)\n\n\n3\n\n\n\n3\n\n+\n3\n×\n\n\n\n(\n6\n)\n\n2\n\n\n      (M1)(M1)

\n

Note: Award (M1) for their correct substitution in volume of sphere formula divided by 2, (M1) for adding their correctly substituted volume of the cuboid.

\n

 

\n

= 165 cm3   (164.548…)      (A1)(ft) (C3)

\n

Note: The answer is 165 cm3; the units are required. Follow through from part (a)(i).

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

their 164.548… × 2.56      (M1)

\n

Note: Award (M1) for multiplying their part (a)(ii) by 2.56.

\n

 

\n

= 421 (g)   (421.244…(g))      (A1)(ft) (C2)

\n

Note: Follow through from part (a)(ii).

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.1.SL.TZ0.T_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Solve \n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\n\n(\n\n\nln\n\n\n2\n\n)\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n<\n2\n\n\n\n(\n\n\nln\n\n\n2\n\n)\n\n2\n\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\n\n(\n\n\nln\n\n\n2\n\n)\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n\n2\n\n\n\n(\n\n\nln\n\n\n2\n\n)\n\n2\n\n\n\n(\n\n=\n0\n\n)\n\n

\n

EITHER

\n

\n\nln\n\n\nx\n=\n\n\n\nln\n\n\n2\n±\n\n\n\n\n\n(\n\n\nln\n\n\n2\n\n)\n\n\n2\n\n\n+\n8\n\n\n\n\n(\n\n\nln\n\n\n2\n\n)\n\n\n2\n\n\n\n\n2\n\n     M1

\n

\n=\n\n\n\nln\n\n\n2\n±\n3\n\n\nln\n\n\n2\n\n2\n\n     A1

\n

OR

\n

\n\n(\n\n\nln\n\n\nx\n\n2\n\n\nln\n\n\n2\n\n)\n\n\n(\n\n\nln\n\n\nx\n+\n2\n\n\nln\n\n\n2\n\n)\n\n\n(\n\n=\n0\n\n)\n\n     M1A1

\n

THEN

\n

\n\nln\n\n\nx\n=\n2\n\n\nln\n\n\n2\n or \n\n\nln\n\n\n2\n     A1

\n

\n\nx\n=\n4\n or \nx\n=\n\n1\n2\n\n       (M1)A1   

\n

Note: (M1) is for an appropriate use of a log law in either case, dependent on the previous M1 being awarded, A1 for both correct answers.

\n

solution is \n\n1\n2\n\n<\nx\n<\n4\n     A1

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ1.H_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

Solve the equation \n\n\n4\nx\n\n\n+\n\n\n2\n\nx\n+\n2\n\n\n\n=\n3\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to form a quadratic in \n\n\n2\nx\n\n\n     M1

\n

\n\n(\n\n\n2\nx\n\n\n\n)\n2\n\n\n+\n4\n\n\n\n2\nx\n\n\n\n3\n=\n0\n    A1

\n

\n\n\n2\nx\n\n\n=\n\n\n\n4\n±\n\n16\n+\n12\n\n\n2\n\n\n \n\n\n(\n\n=\n\n2\n±\n\n7\n\n\n)\n\n    M1

\n

\n\n\n2\nx\n\n\n=\n\n2\n+\n\n7\n\n\n \n\n\n(\n\n\nas \n\n\n2\n\n\n7\n\n<\n0\n\n)\n\n    R1

\n

\nx\n=\n\n\nlog\n2\n\n\n\n(\n\n\n2\n+\n\n7\n\n\n)\n\n\n \n\n\n(\n\nx\n=\n\n\nln\n\n\n(\n\n\n2\n+\n\n7\n\n\n)\n\n\n\nln\n\n2\n\n\n\n)\n\n    A1

\n

 

\n

Note: Award R0 A1 if final answer is \nx\n=\n\n\nlog\n2\n\n\n\n(\n\n\n2\n+\n\n7\n\n\n)\n\n.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.1.AHL.TZ0.H_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

A large company surveyed 160 of its employees to find out how much time they spend traveling to work on a given day. The results of the survey are shown in the following cumulative frequency diagram.

\n

\n
\n

Only 10% of the employees spent more than \nk\n minutes traveling to work.

\n
\n

The results of the survey can also be displayed on the following box-and-whisker diagram.

\n

\n
\n

Find the median number of minutes spent traveling to work.

\n
[2]
\n
a.
\n
\n

Find the number of employees whose travelling time is within 15 minutes of the median.

\n
[3]
\n
b.
\n
\n

Find the value of  k .

\n
[3]
\n
c.
\n
\n

Write down the value of b .

\n
[1]
\n
d.
\n
\n

Find the value of a .

\n
[2]
\n
e.i.
\n
\n

Hence, find the interquartile range.

\n
[2]
\n
e.ii.
\n
\n

Travelling times of less than p minutes are considered outliers.

\n

Find the value of p .

\n
[2]
\n
f.
\n
", "Markscheme": "
\n

evidence of median position         (M1)

\n

80th employee

\n

40 minutes       A1

\n

[2 marks]

\n
a.
\n
\n

valid attempt to find interval (25–55)      (M1)

\n

18 (employees), 142 (employees)      A1

\n

124      A1

\n

[3 marks]

\n
b.
\n
\n

recognising that there are 16 employees in the top 10%     (M1)

\n

144 employees travelled more than k minutes       (A1)

\n

k = 56      A1

\n

[3 marks]

\n
c.
\n
\n

b = 70      A1

\n

[1 mark]

\n
d.
\n
\n

recognizing a is first quartile value      (M1)

\n

40 employees

\n

a = 33      A1

\n

[2 marks]

\n
e.i.
\n
\n

47 − 33       (M1)

\n

IQR = 14      A1

\n

[2 marks]

\n
e.ii.
\n
\n

attempt to find 1.5 × their IQR      (M1)

\n

33 − 21

\n

12       (A1)

\n

[2 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
f.
\n
", "question_id": "SPM.1.SL.TZ0.7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Solve the equation \n\n\nlog\n2\n\n\n(\nx\n+\n3\n)\n+\n\n\nlog\n2\n\n\n(\nx\n\n3\n)\n=\n4\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nlog\n2\n\n\n(\nx\n+\n3\n)\n+\n\n\nlog\n2\n\n\n(\nx\n\n3\n)\n=\n4\n

\n

\n\n\nlog\n2\n\n\n(\n\n\nx\n2\n\n\n\n9\n)\n=\n4\n     (M1)

\n

\n\n\nx\n2\n\n\n\n9\n=\n\n\n2\n4\n\n\n\n \n\n(\n=\n16\n)\n     M1A1

\n

\n\n\nx\n2\n\n\n=\n25\n

\n

\nx\n=\n±\n5\n     (A1)

\n

\nx\n=\n5\n     A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.AHL.TZ0.H_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

The table below shows the distribution of test grades for 50 IB students at Greendale School.

\n

\"M17/5/MATSD/SP2/ENG/TZ1/05\"

\n
\n

A student is chosen at random from these 50 students.

\n
\n

A second student is chosen at random from these 50 students.

\n
\n

The number of minutes that the 50 students spent preparing for the test was normally distributed with a mean of 105 minutes and a standard deviation of 20 minutes.

\n
\n

Calculate the mean test grade of the students;

\n
[2]
\n
a.i.
\n
\n

Calculate the standard deviation.

\n
[1]
\n
a.ii.
\n
\n

Find the median test grade of the students.

\n
[1]
\n
b.
\n
\n

Find the interquartile range.

\n
[2]
\n
c.
\n
\n

Find the probability that this student scored a grade 5 or higher.

\n
[2]
\n
d.
\n
\n

Given that the first student chosen at random scored a grade 5 or higher, find the probability that both students scored a grade 6.

\n
[3]
\n
e.
\n
\n

Calculate the probability that a student chosen at random spent at least 90 minutes preparing for the test.

\n
[2]
\n
f.i.
\n
\n

Calculate the expected number of students that spent at least 90 minutes preparing for the test.

\n
[2]
\n
f.ii.
\n
", "Markscheme": "
\n

\n\n\n1\n(\n1\n)\n+\n3\n(\n2\n)\n+\n7\n(\n3\n)\n+\n13\n(\n4\n)\n+\n11\n(\n5\n)\n+\n10\n(\n6\n)\n+\n5\n(\n7\n)\n\n\n50\n\n\n=\n\n\n230\n\n\n50\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into mean formula.

\n

 

\n

\n=\n4.6\n     (A1)     (G2)

\n

[2 marks]

\n
a.i.
\n
\n

\n1.46\n\n \n\n(\n1.45602\n\n)\n     (G1)

\n

[1 mark]

\n
a.ii.
\n
\n

5     (A1)

\n

[1 mark]

\n
b.
\n
\n

\n6\n\n4\n     (M1)

\n

 

\n

Note:     Award (M1) for 6 and 4 seen.

\n

 

\n

\n=\n2\n     (A1)     (G2)

\n

[2 marks]

\n
c.
\n
\n

\n\n\n11\n+\n10\n+\n5\n\n\n50\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for \n11\n+\n10\n+\n5\n seen.

\n

 

\n

\n=\n\n\n26\n\n\n50\n\n\n\n \n\n\n(\n\n\n\n13\n\n\n25\n\n\n,\n\n \n\n0.52\n,\n\n \n\n52\n%\n\n)\n\n     (A1)     (G2)

\n

[2 marks]

\n
d.
\n
\n

\n\n\n10\n\n\n\ntheir \n\n26\n\n\n×\n\n9\n\n49\n\n\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for \n\n\n10\n\n\n\ntheir \n\n26\n\n\n seen, (M1) for multiplying their first probability by \n\n9\n\n49\n\n\n.

\n

 

\n

OR

\n

\n\n\n\n\n10\n\n\n50\n\n\n×\n\n9\n\n49\n\n\n\n\n\n\n26\n\n\n50\n\n\n\n\n

\n

 

\n

Note:     Award (M1) for \n\n\n\n10\n\n\n50\n\n\n×\n\n9\n\n49\n\n\n\n seen, (M1) for dividing their first probability by \n\n\n\ntheir \n\n26\n\n\n50\n\n\n.

\n

 

\n

\n=\n\n\n45\n\n\n637\n\n\n\n (\n\n0.0706\n,\n\n \n\n0.0706436\n\n,\n\n \n\n7.06436\n\n%\n)\n     (A1)(ft)     (G3)

\n

 

\n

Note:     Follow through from part (d).

\n

 

\n

[3 marks]

\n
e.
\n
\n

\n\nP\n\n(\nX\n\n90\n)\n     (M1)

\n

OR

\n

\"M17/5/MATSD/SP2/ENG/TZ1/05.f.i/M\"     (M1)

\n

 

\n

Note:     Award (M1) for a diagram showing the correct shaded region \n(\n>\n0.5\n)\n.

\n

 

\n

\n0.773\n\n \n\n(\n0.773372\n\n)\n\n \n\n0.773\n\n \n\n(\n0.773372\n\n,\n\n \n\n77.3372\n\n%\n)\n     (A1)     (G2)

\n

[2 marks]

\n
f.i.
\n
\n

\n0.773372\n\n×\n50\n     (M1)

\n

\n=\n38.7\n\n \n\n(\n38.6686\n\n)\n     (A1)(ft)     (G2)

\n

 

\n

Note:     Follow through from part (f)(i).

\n

 

\n

[2 marks]

\n
f.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
", "question_id": "17M.2.SL.TZ1.T_5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

Find the solution of \n\n\nlog\n2\n\n\nx\n\n\n\nlog\n2\n\n\n5\n=\n2\n+\n\n\nlog\n2\n\n\n3\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nlog\n2\n\n\nx\n\n\n\nlog\n2\n\n\n5\n=\n2\n+\n\n\nlog\n2\n\n\n3\n

\n

collecting at least two log terms     (M1)

\n

eg\n\n\n\n\n\n\n\n\nlog\n2\n\n\n\nx\n5\n\n=\n2\n+\n\n\nlog\n2\n\n\n3\n\n or \n\n\n\nlog\n2\n\n\n\nx\n\n15\n\n\n=\n2\n

\n

obtaining a correct equation without logs     (M1)

\n

eg\n\n\n\n\n\n\n\nx\n5\n\n=\n12\n\n\n\n\nOR\n\n\n\n\n\nx\n\n15\n\n\n=\n\n\n2\n2\n\n\n     (A1)

\n

\nx\n=\n60\n     A1

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.AHL.TZ1.H_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

A calculator fits into a cuboid case with height 29 mm, width 98 mm and length 186 mm.

\n
\n

Find the volume, in cm3, of this calculator case.

\n
", "Markscheme": "
\n

evidence of 10 mm = 1 cm     (A1)

\n

Note: Award (A1) for dividing their volume from part (a) or part (b) by 1000.

\n

529 (cm3)  (528.612 (cm3))    (A1)(ft) (C2)

\n

Note: Follow through from parts (a) or (b). Accept answers written in scientific notation.

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.SL.TZ1.T_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Chloe and Selena play a game where each have four cards showing capital letters A, B, C and D.
Chloe lays her cards face up on the table in order A, B, C, D as shown in the following diagram.

\n

\"N17/5/MATHL/HP1/ENG/TZ0/10\"

\n

Selena shuffles her cards and lays them face down on the table. She then turns them over one by one to see if her card matches with Chloe’s card directly above.
Chloe wins if no matches occur; otherwise Selena wins.

\n
\n

Chloe and Selena repeat their game so that they play a total of 50 times.
Suppose the discrete random variable X represents the number of times Chloe wins.

\n
\n

Show that the probability that Chloe wins the game is \n\n3\n8\n\n.

\n
[6]
\n
a.
\n
\n

Determine the mean of X.

\n
[3]
\n
b.i.
\n
\n

Determine the variance of X.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

number of possible “deals” \n=\n4\n!\n=\n24\n     A1

\n

consider ways of achieving “no matches” (Chloe winning):

\n

Selena could deal B, C, D (ie, 3 possibilities)

\n

as her first card     R1

\n

for each of these matches, there are only 3 possible combinations for the remaining 3 cards     R1

\n

so no. ways achieving no matches \n=\n3\n×\n3\n=\n9\n     M1A1

\n

so probability Chloe wins \n=\n\n9\n\n23\n\n\n=\n\n3\n8\n\n     A1AG

\n

 

\n

METHOD 2

\n

number of possible “deals” \n=\n4\n!\n=\n24\n     A1

\n

consider ways of achieving a match (Selena winning)

\n

Selena card A can match with Chloe card A, giving 6 possibilities for this happening     R1

\n

if Selena deals B as her first card, there are only 3 possible combinations for the remaining 3 cards. Similarly for dealing C and dealing D     R1

\n

so no. ways achieving one match is \n=\n6\n+\n3\n+\n3\n+\n3\n=\n15\n     M1A1

\n

so probability Chloe wins \n=\n1\n\n\n\n15\n\n\n24\n\n\n=\n\n3\n8\n\n     A1AG

\n

 

\n

METHOD 3

\n

systematic attempt to find number of outcomes where Chloe wins (no matches)

\n

(using tree diag. or otherwise)     M1

\n

9 found     A1

\n

each has probability \n\n1\n4\n\n×\n\n1\n3\n\n×\n\n1\n2\n\n×\n1\n     M1

\n

\n=\n\n1\n\n24\n\n\n     A1

\n

their 9 multiplied by their \n\n1\n\n24\n\n\n     M1A1

\n

\n=\n\n3\n8\n\n     AG

\n

 

\n

[6 marks]

\n
a.
\n
\n

\nX\n\n\nB\n\n\n(\n\n50\n,\n\n \n\n\n3\n8\n\n\n)\n\n     (M1)

\n

\nμ\n=\nn\np\n=\n50\n×\n\n3\n8\n\n=\n\n\n150\n\n8\n\n\n \n\n\n(\n\n=\n\n\n75\n\n4\n\n\n)\n\n\n \n\n(\n=\n18.75\n)\n     (M1)A1

\n

[3 marks]

\n
b.i.
\n
\n

\n\n\nσ\n2\n\n\n=\nn\np\n(\n1\n\np\n)\n=\n50\n×\n\n3\n8\n\n×\n\n5\n8\n\n=\n\n\n750\n\n\n64\n\n\n\n \n\n\n(\n\n=\n\n\n375\n\n\n32\n\n\n\n)\n\n\n \n\n(\n=\n11.7\n)\n     (M1)A1

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "17N.1.AHL.TZ0.H_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

An archaeological site is to be made accessible for viewing by the public. To do this, archaeologists built two straight paths from point A to point B and from point B to point C as shown in the following diagram. The length of path AB is 185 m, the length of path BC is 250 m, and angle \n\nA\n\n\n\nB\n\n\n\n\n\nC\n\n is 125°.

\n

\n
\n

The archaeologists plan to build two more straight paths, AD and DC. For the paths to go around the site, angle \n\nB\n\n\n\nA\n\n\n\n\n\nD\n\n is to be made equal to 85° and angle \n\nB\n\n\n\nC\n\n\n\n\n\nD\n\n is to be made equal to 70° as shown in the following diagram.

\n

\n
\n

Find the distance from A to C.

\n
[3]
\n
a.
\n
\n

Find the size of angle \n\nB\n\n\n\nA\n\n\n\n\n\nC\n\n.

\n
[3]
\n
b.i.
\n
\n

Find the size of angle \n\nC\n\n\n\nA\n\n\n\n\n\nD\n\n.

\n
[1]
\n
b.ii.
\n
\n

Find the size of angle \n\nA\n\n\n\nC\n\n\n\n\n\nD\n\n.

\n
[2]
\n
c.
\n
\n

The length of path AD is 287 m.

\n

Find the area of the region ABCD.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

AC2 = 1852 + 2502 − 2 × 185 × 250 × cos(125°)   (M1)(A1)

\n

Note: Award (M1) for substitution in the cosine formula; (A1) for correct substitution.

\n

387  (387.015…) (m)      (A1)(G2)

\n

Note: If radians are used the answer is 154 (154.471…), award at most (M1)(A1)(A0).

\n

[3 marks]

\n
a.
\n
\n

\n\n\n250\n\n\n\nsin\n\n\n\nB\n\n\n\nA\n\n\n\n\n\nC\n\n\n\n=\n\n\n387.015\n\n\n\n\nsin\n\n\n\n(\n\n\n125\n\n\n\n)\n\n\n\n       (M1)(A1)(ft)

\n

OR

\n

\n\nco\n\n\n\n\ns\n\n\n\n1\n\n\n\n\n(\n\n\n\n\n\n\n185\n\n2\n\n\n+\n387.015\n\n\n\n2\n\n\n\n\n\n\n250\n\n2\n\n\n\n\n2\n×\n185\n×\n387.015\n\n\n\n\n)\n\n       (M1)(A1)(ft)

\n

Note: Award (M1) for substitution in the sine or cosine formulas; (A1)(ft) for correct substitution.

\n

\n\nB\n\n\n\nA\n\n\n\n\n\nC\n\n=\n\n31\n\n\n\n.9\n\n\n\n  (31.9478…°)       (A1)(ft)(G2)

\n

Note: Follow through from part (a).

\n

[3 marks]

\n
b.i.
\n
\n

(CAD =) 53.1°  (53.0521…°)       (A1)(ft)

\n

Note: Follow through from their part (b)(i) only if working seen.

\n

[1 mark]

\n
b.ii.
\n
\n

(ACD = ) 70° − (180° − 125° − 31.9478°…)      (M1)

\n

Note: Award (M1) for subtracting their angle \n\nA\n\n\n\nC\n\n\n\n\n\nB\n\n from 70°.

\n

OR

\n

(ADC =) 360 − (85 + 70 + 125) = 80

\n

(ACD =) 180 − 80 − 53.0521...      (M1)

\n

46.9°  (46.9478…°)      (A1)(ft)(G2)

\n

Note: Follow through from part (b)(i).

\n

[2 marks]

\n
c.
\n
\n

\n\n\n185\n×\n250\n×\n\nsin\n\n\n\n(\n\n\n125\n\n\n\n)\n\n\n2\n\n+\n\n\n287\n×\n387.015\n\n×\n\nsin\n\n\n\n(\n\n53.0521\n\n\n\n\n\n)\n\n\n2\n\n     (M1)(M1)(M1)

\n

Note: Award (M1) for substitution in the area formula for either triangle; (M1) for correct substitution for both areas; (M1) for adding their two areas;

\n

18942.8… + 44383.9…

\n

63300 (m2)  (63326.8… (m2))      (A1)(ft)(G3)

\n

Note: Follow through from parts (a) and (b)(ii).

\n

OR

\n

\n\nDC\n\n=\n\n\n287\n×\n\nsin\n\n\n\n(\n\n53.0521\n\n\n)\n\n\n\n\nsin\n\n\n\n(\n\n46.9478\n\n\n)\n\n\n\n=\n313.884\n\n

\n

\n0.5\n×\n287\n×\n185\n×\n\nsin\n\n\n\n85\n\n\n+\n0.5\n×\n250\n×\n313.884\n\n×\n\nsin\n\n\n\n70\n\n\n      M1M1M1

\n

Note: Award (M1) for substitution in the area formula for either triangle; (M1) for correct substitution for both areas; (M1) for adding their two areas;

\n

26446.4… + 36869.3

\n

63300  (63315.8…) (m2)     (A1)(ft)(G3)

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.2.SL.TZ2.T_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Place the numbers  2 π , 5 , 3 1 and  2 3 2  in the correct position on the Venn diagram.

\n

\n
[4]
\n
a.
\n
\n

In the table indicate which two of the given statements are true by placing a tick (✔) in the right hand column.

\n

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

    (A1)(A1)(A1)(A1)   (C4)

\n

Note: Award (A1) for each number in the correct position.

\n

[4 marks]

\n
a.
\n
\n

     (A1)(A1)   (C2)

\n

Note: Award (A1) for each correctly placed tick.

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.SL.TZ1.T_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A sphere with diameter 3 474 000 metres can model the shape of the Moon.

\n
\n

Use this model to calculate the circumference of the Moon in kilometres. Give your full calculator display.

\n
[3]
\n
a.
\n
\n

Give your answer to part (a) correct to three significant figures.

\n
[1]
\n
b.
\n
\n

Write your answer to part (b) in the form \na\n×\n\n\n10\nk\n\n\n, where 1 ≤ \na\n < 10 , \nk\n\n\nZ\n\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n3\n\n474\n\n000\n×\nπ\n\n\n1000\n\n\n      (M1)(M1)

\n

Note: Award (M1) for correct numerator and (M1) for dividing by 1000 OR equivalent, such as \n\n\n3\n\n474\n\n000\n×\n2\n×\nπ\n\n\n2000\n\n\n ie diameter.
Do not accept use of area formula ie \nπ\n\n\nr\n2\n\n\n.

\n

10 913.89287… (km)      (A1)  (C3)

\n

[3 marks]

\n

 

\n
a.
\n
\n

10 900 (km)      (A1)(ft)  (C1)

\n

Note: Follow through from part (a).

\n

[1 mark]

\n

 

\n
b.
\n
\n

1.09 × 104      (A1)(ft)(A1)(ft)  (C2)

\n

Note: Follow through from part (b) only. Award (A1)(ft) for 1.09, and (A1)(ft) × 104. Award (A0)(A0) for answers of the type: 10.9 × 103.

\n

[2 marks]

\n

 

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-1-using-standard-form" ] }, { "Question": "
\n

Express the binomial coefficient \n\n(\n\n\n\n3\nn\n+\n1\n\n\n\n\n3\nn\n\n2\n\n\n\n)\n\n as a polynomial in \nn\n.

\n
[3]
\n
a.
\n
\n

Hence find the least value of \nn\n for which \n\n(\n\n\n\n3\nn\n+\n1\n\n\n\n\n3\nn\n\n2\n\n\n\n)\n\n>\n\n\n10\n6\n\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n(\n\n\n\n3\nn\n+\n1\n\n\n\n\n3\nn\n\n2\n\n\n\n)\n\n=\n\n\n\n(\n\n3\nn\n+\n1\n\n)\n\n\n!\n\n\n\n\n(\n\n3\nn\n\n2\n\n)\n\n\n!\n\n3\n\n!\n\n\n\n     (M1)

\n

\n=\n\n\n\n(\n\n3\nn\n+\n1\n\n)\n\n3\nn\n\n(\n\n3\nn\n\n1\n\n)\n\n\n\n3\n\n!\n\n\n\n     A1

\n

\n=\n\n9\n2\n\n\n\nn\n3\n\n\n\n\n1\n2\n\nn\n or equivalent     A1

\n

[3 marks]

\n
a.
\n
\n

attempt to solve \n=\n\n9\n2\n\n\n\nn\n3\n\n\n\n\n1\n2\n\nn\n>\n\n\n10\n6\n\n\n     (M1)

\n

\nn\n>\n60.57\n\n     (A1)

\n

Note: Allow equality.

\n

\n\nn\n=\n61\n     A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.AHL.TZ2.H_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Consider the following sets:

\n

The universal set \nU\n consists of all positive integers less than 15;
\nA\n is the set of all numbers which are multiples of 3;
\nB\n is the set of all even numbers.

\n
\n

Write down the elements that belong to A B .

\n
[3]
\n
a.
\n
\n

Write down the elements that belong to A B .

\n
[2]
\n
b.i.
\n
\n

Write down n ( A B ) .

\n
[1]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

A = {3, 6, 9, 12}  AND  B  = {2, 4, 6, 8, 10, 12, 14}      (M1)

\n

Note: Award (M1) for listing all elements of sets A and B . May be seen in part (b). Condone the inclusion of 15 in set A when awarding the (M1).

\n

6, 12     (A1)(A1)   (C3)  

\n

Note: Award (A1) for each correct element. Award (A1)(A0) if one additional value seen. Award (A0)(A0) if two or more additional values are seen.

\n

[3 marks]

\n
a.
\n
\n

3, 9     (A1)(ft)(A1)(ft)   (C2)  

\n

Note: Follow through from part (a) but only if their A and B are explicitly listed.
Award (A1)(ft) for each correct element. Award (A1)(A0) if one additional value seen. Award (A0)(A0) if two or more additional values are seen.

\n

[2 marks]

\n
b.i.
\n
\n

2     (A1)(ft)   (C1)  

\n

Note: Follow through from part (b)(i).

\n

[1 mark]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "19M.1.SL.TZ2.T_11", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Three girls and four boys are seated randomly on a straight bench. Find the probability that the girls sit together and the boys sit together.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

total number of arrangements 7!     (A1)

\n

number of ways for girls and boys to sit together \n=\n3\n!\n×\n4\n!\n×\n2\n     (M1)(A1)

\n

 

\n

Note:    Award M1A0 if the 2 is missing.

\n

 

\n

probability \n\n\n3\n!\n×\n4\n!\n×\n2\n\n\n7\n!\n\n\n     M1

\n

 

\n

Note:     Award M1 for attempting to write as a probability.

\n

 

\n

\n\n\n2\n×\n3\n×\n4\n!\n×\n2\n\n\n7\n×\n6\n×\n5\n×\n4\n!\n\n\n

\n

\n=\n\n2\n\n35\n\n\n     A1

\n

 

\n

Note:     Award A0 if not fully simplified.

\n

 

\n

METHOD 2

\n

\n\n3\n7\n\n×\n\n2\n6\n\n×\n\n1\n5\n\n+\n\n4\n7\n\n×\n\n3\n6\n\n×\n\n2\n5\n\n×\n\n1\n4\n\n     (M1)A1A1

\n

 

\n

Note:     Accept \n\n3\n7\n\n×\n\n2\n6\n\n×\n\n1\n5\n\n×\n2\n or \n\n4\n7\n\n×\n\n3\n6\n\n×\n\n2\n5\n\n×\n\n1\n4\n\n×\n2\n.

\n

 

\n

\n=\n\n2\n\n35\n\n\n     (M1)A1

\n

 

\n

Note:     Award A0 if not fully simplified.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.AHL.TZ1.H_4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

In this question, give all answers correct to 2 decimal places.

\n

Jose travelled from Buenos Aires to Sydney. He used Argentine pesos, ARS, to buy 350 Australian dollars, AUD, at a bank. The exchange rate was 1 ARS = 0.1559 AUD.

\n
\n

The bank charged Jose a commission of 2%.

\n
\n

Jose used his credit card to pay his hotel bill in Sydney. The bill was 585 AUD. The value the credit card company charged for this payment was 4228.38 ARS. The exchange rate used by the credit card company was 1 AUD = \nx\n ARS. No commission was charged.

\n
\n

Use this exchange rate to calculate the amount of ARS that is equal to 350 AUD.

\n
[2]
\n
a.
\n
\n

Calculate the total amount of ARS Jose paid to get 350 AUD.

\n
[2]
\n
b.
\n
\n

Find the value of \nx\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

Note:     In this question, the first time an answer is not to 2 dp the final (A1) is not awarded.

\n

 

\n

\n\n\n350\n\n\n0.1559\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for dividing 350 by 0.1559.

\n

 

\n

\n=\n2245.03\n\n (ARS)\n\n     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

\n2245.03\n×\n1.02\n     (M1)

\n

 

\n

Note:     Award (M1) for multiplying their answer to part (a) by 1.02.

\n

 

\n

\n=\n2289.93\n\n (ARS)\n\n     (A1)(ft)     (C2)

\n

OR

\n

\n2245.03\n×\n0.02\n     (M1)

\n

 

\n

Note:     Award (M1) for multiplying their answer to part (a) by 0.02.

\n

 

\n

\n=\n44.9006\n

\n

\n2245.03\n+\n44.90\n

\n

\n=\n2289.93\n\n (ARS)\n\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n\n\n4228.38\n\n\n585\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for dividing 4228.38 by 585.

\n

 

\n

\n=\n7.23\n     (A1)     (C2)

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.1.SL.TZ0.T_8", "topics": [], "subtopics": [] }, { "Question": "
\n

The coefficient of x 2 in the expansion of ( 1 x + 5 x ) 8 is equal to the coefficient of x 4 in the expansion of ( a + 5 x ) 7 ,   a R . Find the value of a .

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1

\n

8 C r ( 1 x ) 8 r ( 5 x ) r = 8 C r ( 5 ) r x 2 r 8    (M1)

\n

r = 5      (A1)

\n

8 C 5 × 5 5 = 7 C 4 a 3 × 5 4      M1A1

\n

56 × 5 = 35 a 3

\n

a 3 = 8      (A1)

\n

a = 2      A1

\n

METHOD 2

\n

attempt to expand both binomials     M1

\n

175000 x 2      A1

\n

21875 a 3 x 4      A1

\n

175000 = 21875 a 3      M1

\n

a 3 = 8      (A1)

\n

a = 2      A1

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.AHL.TZ1.H_3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

In a trial examination session a candidate at a school has to take 18 examination papers including the physics paper, the chemistry paper and the biology paper. No two of these three papers may be taken consecutively. There is no restriction on the order in which the other examination papers may be taken.

\n

Find the number of different orders in which these 18 examination papers may be taken.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

consideration of all papers

\n

all papers may be sat in 18! ways     A1

\n

number of ways of positioning “pairs” of science subjects \n=\n3\n!\n×\n17\n!\n     A1

\n

but this includes two copies of each “triple”     (R1)

\n

number of ways of positioning “triplets” of science subjects \n=\n3\n!\n×\n16\n!\n     A1

\n

hence number of arrangements is \n18\n!\n\n3\n!\n×\n17\n!\n+\n3\n!\n×\n16\n!\n     M1A1

\n

\n(\n=\n4.39\n×\n\n\n10\n\n15\n\n\n\n)\n

\n

METHOD 2

\n

consideration of all the non-science papers     (M1)

\n

hence all non-science papers can be sat in 15! ways     A1

\n

there are \n16\n×\n15\n×\n14\n\n \n\n(\n=\n3360\n)\n ways of positioning the three science papers     (M1)A1

\n

hence the number of arrangements is \n16\n×\n15\n×\n14\n×\n15\n!\n\n (\n\n=\n4.39\n×\n\n\n10\n\n15\n\n\n\n)\n     (M1)A1

\n

METHOD 3

\n

consideration of all papers

\n

all papers may be sat in 18! ways     A1

\n

number of ways of positioning exactly two science subjects \n=\n3\n!\n×\n15\n!\n×\n16\n×\n15\n     M1A1

\n

number of ways of positioning “triplets” of science subjects \n=\n3\n!\n×\n16\n!\n     A1

\n

hence number of arrangements is \n18\n!\n\n3\n!\n×\n16\n!\n\n3\n!\n×\n15\n!\n×\n16\n×\n15\n     M1A1

\n

\n(\n=\n4.39\n×\n\n\n10\n\n15\n\n\n\n)\n

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.AHL.TZ2.H_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

A survey was conducted on a group of people. The first question asked how many pets they each own. The results are summarized in the following table.

\n

\n
\n

The second question asked each member of the group to state their age and preferred pet. The data obtained is organized in the following table.

\n

\n
\n

A \n\n\nχ\n2\n\n\n test is carried out at the 10 % significance level.

\n
\n

Write down the total number of people, from this group, who are pet owners.

\n
[1]
\n
a.
\n
\n

Write down the modal number of pets.

\n
[1]
\n
b.
\n
\n

For these data, write down the median number of pets.

\n
[1]
\n
c.i.
\n
\n

For these data, write down the lower quartile.

\n
[1]
\n
c.ii.
\n
\n

For these data, write down the upper quartile.

\n
[1]
\n
c.iii.
\n
\n

Write down the ratio of teenagers to non-teenagers in its simplest form.

\n
[1]
\n
d.
\n
\n

State the null hypothesis.

\n
[1]
\n
e.i.
\n
\n

State the alternative hypothesis.

\n
[1]
\n
e.ii.
\n
\n

Write down the number of degrees of freedom for this test.

\n
[1]
\n
f.
\n
\n

Calculate the expected number of teenagers that prefer cats.

\n
[2]
\n
g.
\n
\n

Use your graphic display calculator to find the \np\n-value for this test.

\n
[2]
\n
h.
\n
\n

State the conclusion for this test. Give a reason for your answer.

\n
[2]
\n
i.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

140       (A1)

\n

[1 mark]

\n
a.
\n
\n

1       (A1)

\n

[1 mark]

\n
b.
\n
\n

2       (A1)

\n

[1 mark]

\n
c.i.
\n
\n

1       (A1)

\n

[1 mark]

\n
c.ii.
\n
\n

3       (A1)

\n

[1 mark]

\n
c.iii.
\n
\n

17:15  OR  \n\n\n17\n\n\n15\n\n\n      (A1)

\n

Note: Award (A0) for 85:75 or 1.13:1.

\n

[1 mark]

\n
d.
\n
\n

preferred pet is independent of “whether or not the respondent was a teenager\" or \"age category”     (A1)

\n

Note: Accept there is no association between pet and age. Do not accept “not related” or “not correlated” or “influenced”.

\n

[1 mark]

\n
e.i.
\n
\n

preferred pet is not independent of age    (A1)(ft)

\n

Note: Follow through from part (e)(i) i.e. award (A1)(ft) if their alternative hypothesis is the negation of their null hypothesis. Accept “associated” or “dependent”.

\n

[1 mark]

\n
e.ii.
\n
\n

3    (A1)

\n

[1 mark]

\n
f.
\n
\n

\n\n\n85\n×\n55\n\n\n160\n\n\n  OR  \n\n\n85\n\n\n160\n\n\n×\n\n\n55\n\n\n160\n\n\n×\n160\n     (M1)

\n

29.2 (29.2187…)      (A1)(G2)

\n

[2 marks]

\n
g.
\n
\n

0.208 (0.208093…)      (G2)

\n

[2 marks]

\n
h.
\n
\n

0.208 > 0.1      (R1)

\n

accept null hypothesis  OR  fail to reject null hypothesis      (A1)(ft)

\n

Note: Award (R1) for a correct comparison of their \np\n-value to the significance level, award (A1)(ft) for the correct result from that comparison. Accept “\np\n-value > 0.1” as part of the comparison but only if their \np\n-value is explicitly seen in part (h). Follow through from their answer to part (h). Do not award (R0)(A1).

\n

[2 marks]

\n
i.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
\n[N/A]\n
i.
\n
", "question_id": "19M.2.SL.TZ1.T_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

A team of four is to be chosen from a group of four boys and four girls.

\n
\n

Find the number of different possible teams that could be chosen.

\n
[3]
\n
a.
\n
\n

Find the number of different possible teams that could be chosen, given that the team must include at least one girl and at least one boy.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\n(\n\n\n\n\n8\n\n\n\n\n4\n\n\n\n\n)\n\n       (A1)

\n

\n=\n\n\n8\n\n!\n\n\n\n4\n\n!\n\n4\n\n!\n\n\n\n=\n\n\n8\n×\n7\n×\n6\n×\n5\n\n\n4\n×\n3\n×\n2\n×\n1\n\n\n=\n7\n×\n2\n×\n5\n       (M1)

\n

= 70       A1

\n

 

\n

METHOD 2

\n

recognition that they need to count the teams with 0 boys, 1 boy… 4 boys      M1

\n

\n1\n+\n\n(\n\n\n\n\n4\n\n\n\n\n1\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n4\n\n\n\n\n3\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n1\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n4\n\n\n\n\n3\n\n\n\n\n)\n\n+\n1\n

\n

\n=\n1\n+\n\n(\n\n4\n×\n4\n\n)\n\n+\n\n(\n\n6\n×\n6\n\n)\n\n+\n\n(\n\n4\n×\n4\n\n)\n\n+\n1\n      (A1)

\n

= 70       A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

EITHER

\n

recognition that the answer is the total number of teams minus the number of teams with all girls or all boys     (M1)

\n

70 − 2

\n

OR

\n

recognition that the answer is the total of the number of teams with 1 boy,

\n

2 boys, 3 boys        (M1)

\n

 

\n

\n\n(\n\n\n\n\n4\n\n\n\n\n1\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n4\n\n\n\n\n3\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n1\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n4\n\n\n\n\n3\n\n\n\n\n)\n\n=\n\n(\n\n4\n×\n4\n\n)\n\n+\n\n(\n\n6\n×\n6\n\n)\n\n+\n\n(\n\n4\n×\n4\n\n)\n\n

\n

THEN

\n

= 68         A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.1.AHL.TZ0.H_2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Consider the curves \n\n\nC\n1\n\n\n and \n\n\nC\n2\n\n\n defined as follows

\n

\n\n\nC\n1\n\n\n\n\n:\n\n\nx\ny\n=\n4\n\nx\n>\n0\n

\n

\n\n\nC\n2\n\n\n\n\n:\n\n\n\n\ny\n2\n\n\n\n\n\nx\n2\n\n\n=\n2\n\nx\n>\n0\n

\n
\n

Using implicit differentiation, or otherwise, find  d y d x  for each curve in terms of  x and  y .

\n
[4]
\n
a.
\n
\n

Let P( a , b ) be the unique point where the curves C 1 and C 2 intersect.

\n

Show that the tangent to C 1 at P is perpendicular to the tangent to C 2 at P.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

C 1 : y + x d y d x = 0       (M1)

\n

Note: M1 is for use of both product rule and implicit differentiation.

\n

 

\n

d y d x = y x       A1

\n

Note: Accept  4 x 2

\n

 

\n

C 2 : 2 y d y d x 2 x = 0       (M1)

\n

d y d x = x y       A1

\n

Note: Accept  ± x 2 + x 2

\n

 

\n

[4 marks]

\n
a.
\n
\n

substituting  a and  b for  x and  y       M1

\n

product of gradients at P is  ( b a ) ( a b ) = 1 or equivalent reasoning       R1

\n

Note: The R1 is dependent on the previous M1

\n

 

\n

so tangents are perpendicular       AG

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.1.AHL.TZ0.H_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-14-implicit-functions-related-rates-optimisation" ] }, { "Question": "
\n

In this question, give all answers to two decimal places.

\n

Karl invests 1000 US dollars (USD) in an account that pays a nominal annual interest of 3.5%, compounded quarterly. He leaves the money in the account for 5 years.

\n
\n

Calculate the amount of money he has in the account after 5 years.

\n
[3]
\n
a.i.
\n
\n

Write down the amount of interest he earned after 5 years.

\n
[1]
\n
a.ii.
\n
\n

Karl decides to donate this interest to a charity in France. The charity receives 170 euros (EUR). The exchange rate is 1 USD = t EUR.

\n

Calculate the value of t.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

1000 ( 1 + 3.5 4 × 100 ) 4 × 5      (M1)(A1)

\n

Note: Award (M1) for substitution in compound interest formula, (A1) for correct substitution.

\n

OR

\n

N = 5

\n

I = 3.5

\n

PV = 1000

\n

P/Y = 1

\n

C/Y = 4

\n

Note: Award (A1) for C/Y = 4 seen, (M1) for other correct entries.

\n

OR

\n

N = 5 × 4

\n

I = 3.5

\n

PV = 1000

\n

P/Y = 1

\n

C/Y = 4

\n

Note: Award (A1) for C/Y = 4 seen, (M1) for other correct entries.

\n

= 1190.34 (USD)     (A1)

\n

Note: Award (M1) for substitution in compound interest formula, (A1) for correct substitution.

\n

[3 marks]

\n
a.i.
\n
\n

190.34 (USD)      (A1)(ft) (C4)

\n

Note: Award (A1)(ft) for subtraction of 1000 from their part (a)(i). Follow through from (a)(i).

\n

[1 mark]

\n
a.ii.
\n
\n

170 190.34      (M1)

\n

Note: Award (M1) for division of 170 by their part (a)(ii).

\n

= 0.89     (A1)(ft) (C2)

\n

Note: Follow through from their part (a)(ii).

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ2.T_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

Differentiate from first principles the function \nf\n\n(\nx\n)\n\n=\n3\n\n\nx\n3\n\n\n\nx\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\n\nf\n\n(\n\nx\n+\nh\n\n)\n\n\nf\n\n(\nx\n)\n\n\nh\n\n

\n

\n=\n\n\n\n(\n\n3\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n3\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n)\n\n\n\n(\n\n3\n\n\nx\n3\n\n\n\nx\n\n)\n\n\nh\n\n    M1

\n

\n=\n\n\n3\n\n(\n\n\n\nx\n3\n\n\n+\n3\n\n\nx\n2\n\n\nh\n+\n3\nx\n\n\nh\n2\n\n\n+\n\n\nh\n3\n\n\n\n)\n\n\nx\n\nh\n\n\n3\n\nx\n3\n\n\n+\nx\n\nh\n\n     (A1)

\n

\n=\n\n\n9\n\n\nx\n2\n\n\nh\n+\n9\nx\n\n\nh\n2\n\n\n+\n3\n\n\nh\n3\n\n\n\nh\n\nh\n\n      A1

\n

cancelling \nh\n      M1

\n

\n=\n9\n\n\nx\n2\n\n\n+\n9\nx\nh\n+\n3\n\n\nh\n2\n\n\n\n1\n

\n

then \n\n\n\nlim\n\n\n\nh\n\n0\n\n\n\n\n(\n\n9\n\n\nx\n2\n\n\n+\n9\nx\nh\n+\n3\n\n\nh\n2\n\n\n\n1\n\n)\n\n

\n

\n=\n9\n\n\nx\n2\n\n\n\n1\n      A1

\n

Note: Final A1 dependent on all previous marks.

\n

 

\n

METHOD 2

\n

\n\n\nf\n\n(\n\nx\n+\nh\n\n)\n\n\nf\n\n(\nx\n)\n\n\nh\n\n

\n

\n=\n\n\n\n(\n\n3\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n3\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n)\n\n\n\n(\n\n3\n\n\nx\n3\n\n\n\nx\n\n)\n\n\nh\n\n    M1

\n

\n=\n\n\n3\n\n(\n\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n3\n\n\n\n\n\nx\n3\n\n\n\n)\n\n+\n\n(\n\nx\n\n\n(\n\nx\n+\nh\n\n)\n\n\n)\n\n\nh\n\n       (A1)

\n

\n=\n\n\n3\nh\n\n(\n\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n2\n\n\n+\nx\n\n(\n\nx\n+\nh\n\n)\n\n+\n\n\nx\n2\n\n\n\n)\n\n\nh\n\nh\n\n      A1

\n

cancelling \nh\n      M1

\n

\n=\n3\n\n(\n\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n2\n\n\n+\nx\n\n(\n\nx\n+\nh\n\n)\n\n+\n\n\nx\n2\n\n\n\n)\n\n\n1\n

\n

then \n\n\n\nlim\n\n\n\nh\n\n0\n\n\n\n\n(\n\n3\n\n(\n\n\n\n\n\n(\n\nx\n+\nh\n\n)\n\n\n2\n\n\n+\nx\n\n(\n\nx\n+\nh\n\n)\n\n+\n\n\nx\n2\n\n\n\n)\n\n\n1\n\n)\n\n

\n

\n=\n9\n\n\nx\n2\n\n\n\n1\n      A1

\n

Note: Final A1 dependent on all previous marks.

\n

 

\n

[5 marks]

\n

 

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.2.AHL.TZ0.H_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

Sila High School has 110 students. They each take exactly one language class from a choice of English, Spanish or Chinese. The following table shows the number of female and male students in the three different language classes.

\n

\n

A \n\n\nχ\n2\n\n\n test was carried out at the 5 % significance level to analyse the relationship between gender and student choice of language class.

\n
\n

Use your graphic display calculator to write down

\n
\n

The critical value at the 5 % significance level for this test is 5.99.

\n
\n

One student is chosen at random from this school.

\n
\n

Another student is chosen at random from this school.

\n
\n

Write down the null hypothesis, H, for this test.

\n
[1]
\n
a.
\n
\n

State the number of degrees of freedom.

\n
[1]
\n
b.
\n
\n

the expected frequency of female students who chose to take the Chinese class.

\n
[1]
\n
c.i.
\n
\n

the \n\n\nχ\n2\n\n\n statistic.

\n
[2]
\n
c.ii.
\n
\n

State whether or not H0 should be rejected. Justify your statement.

\n
[2]
\n
d.
\n
\n

Find the probability that the student does not take the Spanish class.

\n
[2]
\n
e.i.
\n
\n

Find the probability that neither of the two students take the Spanish class.

\n
[3]
\n
e.ii.
\n
\n

Find the probability that at least one of the two students is female.

\n
[3]
\n
e.iii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(H0:) (choice of) language is independent of gender       (A1)

\n

Note: Accept “there is no association between language (choice) and gender”. Accept “language (choice) is not dependent on gender”. Do not accept “not related” or “not correlated” or “not influenced”.

\n

[1 mark]

\n
a.
\n
\n

2       (AG)

\n

[1 mark]

\n
b.
\n
\n

16.4  (16.4181…)      (G1)

\n

[1 mark]

\n
c.i.
\n
\n

\n\nχ\n\n\ncalc\n\n\n2\n\n=\n8.69\n  (8.68507…)     (G2)

\n

[2 marks]

\n
c.ii.
\n
\n

(we) reject the null hypothesis      (A1)(ft)

\n

8.68507… > 5.99     (R1)(ft)

\n

Note: Follow through from part (c)(ii). Accept “do not accept” in place of “reject.” Do not award (A1)(ft)(R0).

\n

OR

\n

(we) reject the null hypothesis       (A1)

\n

0.0130034 < 0.05       (R1)

\n

Note: Accept “do not accept” in place of “reject.” Do not award (A1)(ft)(R0).

\n

[2 marks]

\n
d.
\n
\n

\n\n\n88\n\n\n110\n\n\n\n\n\n\n(\n\n\n4\n5\n\n\n,\n\n\n\n0.8\n\n,\n\n\n\n80\n\n\n\n\n)\n\n   (A1)(A1)(G2)

\n

Note: Award (A1) for correct numerator, (A1) for correct denominator.

\n

 

\n

[2 marks]

\n
e.i.
\n
\n

\n\n\n88\n\n\n110\n\n\n×\n\n\n87\n\n\n109\n\n\n    (M1)(M1)

\n

Note: Award (M1) for multiplying two fractions. Award (M1) for multiplying their correct fractions.

\n

OR

\n

\n\n(\n\n\n\n46\n\n\n110\n\n\n\n)\n\n\n(\n\n\n\n45\n\n\n109\n\n\n\n)\n\n+\n2\n\n(\n\n\n\n46\n\n\n110\n\n\n\n)\n\n\n(\n\n\n\n42\n\n\n109\n\n\n\n)\n\n+\n\n(\n\n\n\n42\n\n\n110\n\n\n\n)\n\n\n(\n\n\n\n41\n\n\n109\n\n\n\n)\n\n    (M1)(M1)

\n

Note: Award (M1) for correct products; (M1) for adding 4 products.

\n

\n0.639\n\n\n\n\n(\n\n0.638532\n\n\n,\n\n\n\n\n\n348\n\n\n545\n\n\n\n,\n\n\n\n63.9\n\n\n\n\n)\n\n       (A1)(ft)(G2)

\n

Note: Follow through from their answer to part (e)(i).

\n

[3 marks]

\n
e.ii.
\n
\n

\n1\n\n\n\n67\n\n\n110\n\n\n×\n\n\n66\n\n\n109\n\n\n   (M1)(M1)

\n

Note: Award (M1) for multiplying two correct fractions. Award (M1) for subtracting their product of two fractions from 1.

\n

OR

\n

\n\n\n43\n\n\n110\n\n\n×\n\n\n42\n\n\n109\n\n\n+\n\n\n43\n\n\n110\n\n\n×\n\n\n67\n\n\n109\n\n\n+\n\n\n67\n\n\n110\n\n\n×\n\n\n43\n\n\n109\n\n\n   (M1)(M1)

\n

Note: Award (M1) for correct products; (M1) for adding three products.

\n

\n0.631\n\n\n\n\n(\n\n0.631192\n\n\n,\n\n\n\n63.1\n\n% ,\n\n\n\n\n\n344\n\n\n545\n\n\n\n)\n\n      (A1)(G2)

\n

[3 marks]

\n
e.iii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
e.iii.
\n
", "question_id": "19M.2.SL.TZ2.T_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A curve has equation \n3\nx\n\n2\n\n\ny\n2\n\n\n\n\n\ne\n\n\nx\n\n1\n\n\n\n=\n2\n.

\n
\n

Find an expression for d y d x  in terms of x and y .

\n
[5]
\n
a.
\n
\n

Find the equations of the tangents to this curve at the points where the curve intersects the line x = 1 .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to differentiate implicitly     M1

\n

3 ( 4 y d y d x + 2 y 2 ) e x 1 = 0    A1A1A1

\n

 

\n

Note: Award A1 for correctly differentiating each term.

\n

 

\n

d y d x = 3 e 1 x 2 y 2 4 y    A1

\n

 

\n

Note: This final answer may be expressed in a number of different ways.

\n

 

\n

[5 marks]

\n
a.
\n
\n

3 2 y 2 = 2 y 2 = 1 2 y = ± 1 2    A1

\n

d y d x = 3 2 1 2 ± 4 1 2 = ± 2 2    M1

\n

at ( 1 ,   1 2 )  the tangent is y 1 2 = 2 2 ( x 1 )  and     A1

\n

at ( 1 ,   1 2 )  the tangent is y + 1 2 = 2 2 ( x 1 )      A1

\n

 

\n

Note: These equations simplify to y = ± 2 2 x .

\n

 

\n

Note: Award A0M1A1A0 if just the positive value of y is considered and just one tangent is found.

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.AHL.TZ0.H_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-14-implicit-functions-related-rates-optimisation" ] }, { "Question": "
\n

Two distinct lines, \n\n\nl\n1\n\n\n and \n\n\nl\n2\n\n\n, intersect at a point \n\nP\n\n. In addition to \n\nP\n\n, four distinct points are marked out on \n\n\nl\n1\n\n\n and three distinct points on \n\n\nl\n2\n\n\n. A mathematician decides to join some of these eight points to form polygons.

\n
\n

The line \n\n\nl\n1\n\n\n has vector equation r1 \n=\n\n(\n\n\n\n\n1\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n1\n\n\n\n\n2\n\n\n\n\n1\n\n\n\n\n)\n\n\nλ\n\n\nR\n\n and the line \n\n\nl\n2\n\n\n has vector equation r2 \n=\n\n(\n\n\n\n\n\n\n1\n\n\n\n\n\n0\n\n\n\n\n2\n\n\n\n\n)\n\n+\nμ\n\n(\n\n\n\n\n5\n\n\n\n\n6\n\n\n\n\n2\n\n\n\n\n)\n\n\nμ\n\n\nR\n\n.

\n

The point \n\nP\n\n has coordinates (4, 6, 4).

\n
\n

The point \n\nA\n\n has coordinates (3, 4, 3) and lies on \n\n\nl\n1\n\n\n.

\n
\n

The point \n\nB\n\n has coordinates (−1, 0, 2) and lies on \n\n\nl\n2\n\n\n.

\n
\n

Find how many sets of four points can be selected which can form the vertices of a quadrilateral.

\n
[2]
\n
a.i.
\n
\n

Find how many sets of three points can be selected which can form the vertices of a triangle.

\n
[4]
\n
a.ii.
\n
\n

Verify that \n\nP\n\n is the point of intersection of the two lines.

\n
[3]
\n
b.
\n
\n

Write down the value of \nλ\n corresponding to the point \n\nA\n\n.

\n
[1]
\n
c.
\n
\n

Write down \n\n\nPA\n\n\n\n and \n\n\nPB\n\n\n\n.

\n
[2]
\n
d.
\n
\n

Let \n\nC\n\n be the point on \n\n\nl\n1\n\n\n with coordinates (1, 0, 1) and \n\nD\n\n be the point on \n\n\nl\n2\n\n\n with parameter \nμ\n=\n\n2\n.

\n

Find the area of the quadrilateral \n\nCDBA\n\n.

\n
[8]
\n
e.
\n
", "Markscheme": "
\n

appreciation that two points distinct from P need to be chosen from each line   M1

\n

4 C 2 × 3 C 2

\n

=18    A1

\n

[2 marks]

\n
a.i.
\n
\n

EITHER

\n

consider cases for triangles including \n\nP\n\n or triangles not including \n\nP\n\n      M1

\n

\n3\n×\n4\n+\n4\n×\n\n\n\n3\n\n\n\nC\n2\n\n\n+\n3\n×\n\n\n\n4\n\n\n\nC\n2\n\n\n     (A1)(A1)

\n

Note: Award A1 for 1st term, A1 for 2nd & 3rd term.

\n

OR

\n

consider total number of ways to select 3 points and subtract those with 3 points on the same line      M1

\n

\n\n\n\n8\n\n\n\nC\n3\n\n\n\n\n\n\n5\n\n\n\nC\n3\n\n\n\n\n\n\n4\n\n\n\nC\n3\n\n\n     (A1)(A1)

\n

Note: Award A1 for 1st term, A1 for 2nd & 3rd term.

\n

56−10−4

\n

THEN

\n

= 42    A1

\n

[4 marks]

\n
a.ii.
\n
\n

METHOD 1

\n

substitution of (4, 6, 4) into both equations       (M1)

\n

\nλ\n=\n3\n and \nμ\n=\n1\n       A1A1

\n

(4, 6, 4)       AG

\n

METHOD 2

\n

attempting to solve two of the three parametric equations      M1

\n

\nλ\n=\n3\n and \nμ\n=\n1\n       A1

\n

check both of the above give (4, 6, 4)       M1AG

\n

Note: If they have shown the curve intersects for all three coordinates they only need to check (4,6,4) with one of \"\nλ\n\" or \"\nμ\n\".

\n

[3 marks]

\n
b.
\n
\n

\nλ\n=\n2\n      A1

\n

[1 mark]

\n
c.
\n
\n

\n\n\nPA\n\n\n\n=\n\n(\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n2\n\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n ,  \n\n\nPB\n\n\n\n=\n\n(\n\n\n\n\n\n\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\n\n\n2\n\n\n\n\n\n)\n\n    A1A1

\n

Note: Award A1A0 if both are given as coordinates.

\n

[2 marks]

\n
d.
\n
\n

METHOD 1

\n

area triangle \n\nABP\n\n=\n\n1\n2\n\n\n|\n\n\n\nPB\n\n\n\n×\n\n\nPA\n\n\n\n\n|\n\n    M1

\n

\n\n(\n\n=\n\n1\n2\n\n\n|\n\n\n(\n\n\n\n\n\n\n5\n\n\n\n\n\n\n\n6\n\n\n\n\n\n\n\n2\n\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n2\n\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n\n|\n\n\n)\n\n=\n\n1\n2\n\n\n|\n\n\n(\n\n\n\n\n2\n\n\n\n\n\n\n3\n\n\n\n\n\n4\n\n\n\n\n)\n\n\n|\n\n    A1

\n

\n=\n\n\n\n29\n\n\n2\n\n    A1

\n

EITHER

\n

\n\n\nPC\n\n\n\n=\n3\n\n\n\n\nPA\n\n\n\n\n\n\n\nPD\n\n\n\n=\n3\n\n\n\n\nPB\n\n\n\n\n       (M1)

\n

area triangle \n\nPCD\n\n=\n9\n×\n area triangle \n\nABP\n\n       (M1)A1

\n

\n=\n\n\n9\n\n29\n\n\n2\n\n    A1

\n

OR

\n

\n\nD\n\n has coordinates (−11, −12, −2)    A1

\n

area triangle \n\nPCD\n\n=\n\n1\n2\n\n\n|\n\n\n\nPD\n\n\n\n×\n\n\nPC\n\n\n\n\n|\n\n=\n\n1\n2\n\n\n|\n\n\n(\n\n\n\n\n\n\n15\n\n\n\n\n\n\n\n18\n\n\n\n\n\n\n\n6\n\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\n6\n\n\n\n\n\n\n\n3\n\n\n\n\n\n)\n\n\n|\n\n    M1A1

\n

Note: A1 is for the correct vectors in the correct formula.

\n

\n=\n\n\n9\n\n29\n\n\n2\n\n    A1

\n

THEN

\n

area of \n\nCDBA\n\n=\n\n\n9\n\n29\n\n\n2\n\n\n\n\n\n29\n\n\n2\n\n

\n

\n=\n4\n\n29\n\n    A1

\n

 

\n

METHOD 2

\n

\n\nD\n\n has coordinates (−11, −12, −2)    A1

\n

area \n=\n\n1\n2\n\n\n|\n\n\n\nCB\n\n\n\n×\n\n\nCA\n\n\n\n\n|\n\n+\n\n1\n2\n\n\n|\n\n\n\nBC\n\n\n\n×\n\n\nBD\n\n\n\n\n|\n\n      M1

\n

Note: Award M1 for use of correct formula on appropriate non-overlapping triangles.

\n

Note: Different triangles or vectors could be used.

\n

\n\n\nCB\n\n\n\n=\n\n(\n\n\n\n\n\n\n2\n\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n\n\n\nCA\n\n\n\n=\n\n(\n\n\n\n\n2\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n    A1

\n

\n\n\nCB\n\n\n\n×\n\n\nCA\n\n\n\n=\n\n(\n\n\n\n\n\n\n4\n\n\n\n\n\n6\n\n\n\n\n\n\n8\n\n\n\n\n\n)\n\n    A1

\n

\n\n\nBC\n\n\n\n=\n\n(\n\n\n\n\n2\n\n\n\n\n0\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n\n\n\nBD\n\n\n\n=\n\n(\n\n\n\n\n\n\n10\n\n\n\n\n\n\n\n12\n\n\n\n\n\n\n\n4\n\n\n\n\n\n)\n\n    A1

\n

\n\n\nBC\n\n\n\n×\n\n\nBD\n\n\n\n=\n\n(\n\n\n\n\n\n\n12\n\n\n\n\n\n\n18\n\n\n\n\n\n\n\n24\n\n\n\n\n\n)\n\n    A1

\n

Note: Other vectors which might be used are \n\n\nDA\n\n\n\n=\n\n(\n\n\n\n\n\n14\n\n\n\n\n\n\n16\n\n\n\n\n\n\n5\n\n\n\n\n\n)\n\n\n\n\nBA\n\n\n\n=\n\n(\n\n\n\n\n\n4\n\n\n\n\n\n\n4\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n\n\n\nDC\n\n\n\n=\n\n(\n\n\n\n\n\n12\n\n\n\n\n\n\n12\n\n\n\n\n\n\n3\n\n\n\n\n\n)\n\n.

\n

Note: Previous A1A1A1A1 are all dependent on the first M1.

\n

valid attempt to find a value of \n\n1\n2\n\n\n|\n\na\n×\nb\n\n|\n\n      M1

\n

Note: M1 independent of triangle chosen.

\n

area \n=\n\n1\n2\n\n×\n2\n×\n\n29\n\n+\n\n1\n2\n\n×\n6\n×\n\n29\n\n

\n

\n=\n4\n\n29\n\n    A1

\n

Note: accept \n\n1\n2\n\n\n116\n\n+\n\n1\n2\n\n\n1044\n\n or equivalent.

\n

 

\n

[8 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "19M.1.AHL.TZ1.H_11", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices", "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

The diagram shows a circular horizontal board divided into six equal sectors. The sectors are labelled white (W), yellow (Y) and blue (B).

\n

\n

A pointer is pinned to the centre of the board. The pointer is to be spun and when it stops the colour of the sector on which the pointer stops is recorded. The pointer is equally likely to stop on any of the six sectors.

\n

Eva will spin the pointer twice. The following tree diagram shows all the possible outcomes.

\n

\n
\n

Find the probability that both spins are yellow.

\n
[2]
\n
a.
\n
\n

Find the probability that at least one of the spins is yellow.

\n
[3]
\n
b.
\n
\n

Write down the probability that the second spin is yellow, given that the first spin is blue.

\n
[1]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n1\n3\n\n×\n\n1\n3\n\n  OR  \n\n\n\n(\n\n\n1\n3\n\n\n)\n\n2\n\n\n  (M1)

\n

Note: Award (M1) for multiplying correct probabilities.

\n

\n\n1\n9\n\n (0.111, 0.111111…, 11.1%)      (A1)   (C2)

\n

[2 marks]

\n
a.
\n
\n

\n\n(\n\n\n1\n2\n\n×\n\n1\n3\n\n\n)\n\n+\n\n(\n\n\n1\n6\n\n×\n\n1\n3\n\n\n)\n\n+\n\n1\n3\n\n       (M1)(M1)

\n

Note: Award (M1) for \n\n(\n\n\n1\n2\n\n×\n\n1\n3\n\n\n)\n\n and \n\n(\n\n\n1\n6\n\n×\n\n1\n3\n\n\n)\n\n or equivalent, and (M1) for \n\n1\n3\n\n and adding only the three correct probabilities.

\n

OR

\n

\n1\n\n\n\n\n(\n\n\n2\n3\n\n\n)\n\n2\n\n\n       (M1)(M1)

\n

Note: Award (M1) for \n\n\n2\n3\n\n\n seen and (M1) for subtracting \n\n\n\n(\n\n\n2\n3\n\n\n)\n\n2\n\n\n from 1. This may be shown in a tree diagram with “yellow” and “not yellow” branches.

\n

\n\n5\n9\n\n (0.556, 0.555555…, 55.6%)      (A1)(ft)   (C3)

\n

Note: Follow through marks may be awarded if their answer to part (a) is used in a correct calculation.

\n

[3 marks]

\n
b.
\n
\n

 

\n

\n\n1\n3\n\n  (0.333, 0.333333…, 33.3%)      (A1)   (C1)

\n

[1 mark]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ1.T_12", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Daniela is going for a holiday to South America. She flies from the US to Argentina stopping in Peru on the way.

\n

In Peru she exchanges 85 United States dollars (USD) for Peruvian nuevo sol (PEN). The exchange rate is 1 USD = 3.25 PEN and a flat fee of 5 USD commission is charged.

\n
\n

At the end of Daniela’s holiday she has 370 Argentinean peso (ARS). She converts this back to USD at a bank that charges a 4% commission on the exchange. The exchange rate is 1 USD = 9.60 ARS.

\n
\n

Calculate the amount of PEN she receives.

\n
[3]
\n
a.
\n
\n

Calculate the amount of USD she receives.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n(\n85\n\n5\n)\n×\n3.25\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for subtracting 5 from 85, (M1) for multiplying by 3.25.

\n

Award (M1) for \n85\n×\n3.25\n, (M1) for subtracting \n5\n×\n3.25\n.

\n

 

\n

\n=\n260\n\n (PEN)\n\n     (A1)     (C3)

\n

[3 marks]

\n
a.
\n
\n

\n\n\n(\n370\n×\n0.96\n)\n\n\n9.6\n\n\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for multiplying by 0.96 (or equivalent), (M1) for dividing by 9.6. If division by 3.25 seen in part (a), condone multiplication by 9.6 in part (b).

\n

 

\n

\n=\n37\n\n (USD)\n\n     (A1)     (C3)

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ1.T_8", "topics": [], "subtopics": [] }, { "Question": "
\n

The curve \nC\n is given by the equation \ny\n=\nx\n\n\ntan\n\n\n(\n\n\n\nπ\nx\ny\n\n4\n\n\n)\n\n.

\n
\n

At the point (1, 1) , show that  d y d x = 2 + π 2 π .

\n
[5]
\n
a.
\n
\n

Hence find the equation of the normal to C at the point (1, 1).

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to differentiate implicitly     M1

\n

d y d x = x se c 2 ( π x y 4 ) [ ( π 4 x d y d x + π 4 y ) ] + tan ( π x y 4 )      A1A1

\n

Note: Award A1 for each term.

\n

attempt to substitute x = 1 , y = 1 into their equation for  d y d x      M1

\n

d y d x = π 2 d y d x + π 2 + 1

\n

d y d x ( 1 π 2 ) = π 2 + 1      A1

\n

d y d x = 2 + π 2 π      AG

\n

[5 marks]

\n
a.
\n
\n

attempt to use gradient of normal  = 1 d y d x        (M1)

\n

= π 2 π + 2

\n

so equation of normal is  y 1 = π 2 π + 2 ( x 1 ) or  y = π 2 π + 2 x + 4 π + 2        A1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.AHL.TZ2.H_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Claudia travels from Buenos Aires to Barcelona. She exchanges 8000 Argentine Pesos (ARS) into Euros (EUR).

\n

The exchange rate is 1 ARS = 0.09819 EUR. The bank charges a 2% commission on the exchange.

\n
\n

When Claudia returns to Buenos Aires she has 85 EUR left and exchanges this money back into ARS. The exchange rate is 1 ARS = 0.08753 EUR. The bank charges \nr\n% commission. The commission charged on this exchange is 14.57 ARS.

\n
\n

Find the amount of Euros that Claudia receives. Give your answer correct to two decimal places.

\n
[3]
\n
a.
\n
\n

Find the value of \nr\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n8000\n×\n0.09819\n×\n0.98\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for multiplying 8000 by 0.09819, (M1) for multiplying by 0.98 (or equivalent).

\n

 

\n

769.81 (EUR)     (A1)     (C3)

\n

[3 marks]

\n
a.
\n
\n

\nr\n%\n×\n\n\n85\n\n\n0.08753\n\n\n=\n14.57\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for dividing 85 by 0.08753, and (M1) for multiplying their \n\n\n85\n\n\n0.08753\n\n\n by \nr\n%\n and equating to 14.57.

\n

 

\n

OR

\n

\n\n\n85\n\n\n0.08753\n\n\n=\n\n971.095\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for dividing 85 by 0.08753.

\n

 

\n

\n\n\n14.57\n\n\n9.71095\n\n\n\n\n\n\n\nOR\n\n\n\n\n\n\n14.57\n\n\n971.095\n\n\n\n×\n100\n     (M1)

\n

 

\n

Note:     Award (M1) for dividing 14.57 by 9.71095… or equivalent.

\n

 

\n

\nr\n=\n1.50\n\n \n\n(\n1.50036\n\n)\n     (A1)     (C3)

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ2.T_8", "topics": [], "subtopics": [] }, { "Question": "
\n

Consider the functions \nf\n,\n\n\ng\n,\n defined for \nx\n\n\nR\n\n, given by \nf\n\n(\nx\n)\n\n=\n\n\n\ne\n\n\n\nx\n\n\n\n\n\nsin\n\n\nx\n and \ng\n\n(\nx\n)\n\n=\n\n\n\ne\n\n\n\nx\n\n\n\n\n\ncos\n\n\nx\n.

\n
\n

Hence, or otherwise, find \n\n\n0\nπ\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\nsin\n\n\nx\n\n\nd\n\nx\n\n.

\n
", "Markscheme": "
\n

METHOD 1

\n

Attempt to add \n\nf\n\n\n\n(\nx\n)\n\n and \n\ng\n\n\n\n(\nx\n)\n\n      (M1)

\n

\n\nf\n\n\n\n(\nx\n)\n\n+\n\ng\n\n\n\n(\nx\n)\n\n=\n\n2\n\n\n\ne\n\n\n\nx\n\n\n\n\n\nsin\n\n\nx\n    A1

\n

\n\n\n0\nπ\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\nsin\n\n\nx\n\n\nd\n\nx\n\n=\n\n\n[\n\n\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n2\n\n\n(\n\n\nsin\n\n\nx\n+\n\ncos\n\n\nx\n\n)\n\n\n]\n\n0\nπ\n\n (or equivalent)      A1

\n

Note: Condone absence of limits.

\n

\n=\n\n1\n2\n\n\n(\n\n1\n+\n\n\n\ne\n\n\n\nπ\n\n\n\n\n)\n\n    A1

\n

 

\n

METHOD 2

\n

\nI\n=\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\n\nsin\n\n\nx\n\n\nd\n\nx\n

\n

\n=\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\ncos\n\n\nx\n\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\n\ncos\n\n\nx\n\n\nd\n\nx\n OR \n=\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\nsin\n\n\nx\n+\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\n\ncos\n\n\nx\n\n\nd\n\nx\n     M1A1

\n

\n=\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\nsin\n\n\nx\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\ncos\n\n\nx\n\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\n\nsin\n\n\nx\n\n\nd\n\nx\n

\n

\nI\n=\n\n1\n2\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n(\n\n\nsin\n\n\nx\n+\n\ncos\n\n\nx\n\n)\n\n     A1

\n

\n\n\n0\nπ\n\n\n\n\n\ne\n\n\n\nx\n\n\n\n\n\nsin\n\n\nx\n\n\nd\n\nx\n=\n\n1\n2\n\n\n(\n\n1\n+\n\n\n\ne\n\n\n\nπ\n\n\n\n\n)\n\n\n    A1

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ2.H_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

The Home Shine factory produces light bulbs, 7% of which are found to be defective.

\n
\n

Francesco buys two light bulbs produced by Home Shine.

\n
\n

The Bright Light factory also produces light bulbs. The probability that a light bulb produced by Bright Light is not defective is \na\n.

\n

Deborah buys three light bulbs produced by Bright Light.

\n
\n

Write down the probability that a light bulb produced by Home Shine is not defective.

\n
[1]
\n
a.
\n
\n

Find the probability that both light bulbs are not defective.

\n
[2]
\n
b.i.
\n
\n

Find the probability that at least one of Francesco’s light bulbs is defective.

\n
[2]
\n
b.ii.
\n
\n

Write down an expression, in terms of \na\n, for the probability that at least one of Deborah’s three light bulbs is defective.

\n
[1]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

0.93 (93%)     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

\n0.93\n×\n0.93\n     (M1)

\n

 

\n

Note:     Award (M1) for squaring their answer to part (a).

\n

 

\n

0.865 (0.8649; 86.5%)     (A1)(ft)     (C2)

\n

 

\n

Notes:     Follow through from part (a).

\n

Accept \n0.86\n\n \n\n\n(\n\n\nunless it follows \n\n\n\n93\n\n\n100\n\n\n×\n\n\n92\n\n\n99\n\n\n\n)\n\n.

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

\n1\n\n0.8649\n     (M1)

\n

 

\n

Note:     Follow through from their answer to part (b)(i).

\n

 

\n

OR

\n

\n0.07\n×\n0.07\n+\n2\n×\n(\n0.07\n×\n0.93\n)\n     (M1)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

0.135 (0.1351; 13.5%)     (A1)(ft)     (C2)

\n

[2 marks]

\n
b.ii.
\n
\n

\n1\n\n\n\na\n3\n\n\n     (A1)     (C1)

\n

 

\n

Note:     Accept \n3\n\n\na\n2\n\n\n(\n1\n\na\n)\n+\n3\na\n\n(\n1\n\na\n\n)\n2\n\n\n+\n\n(\n1\n\na\n\n)\n3\n\n\n or equivalent.

\n

 

\n

[1 mark]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

John purchases a new bicycle for 880 US dollars (USD) and pays for it with a Canadian credit card. There is a transaction fee of 4.2 % charged to John by the credit card company to convert this purchase into Canadian dollars (CAD).

\n

The exchange rate is 1 USD = 1.25 CAD.

\n
\n

John insures his bicycle with a US company. The insurance company produces the following table for the bicycle’s value during each year.

\n

\n

The values of the bicycle form a geometric sequence.

\n
\n

During the 1st year John pays 120 USD to insure his bicycle. Each year the amount he pays to insure his bicycle is reduced by 3.50 USD.

\n
\n

Calculate, in CAD, the total amount John pays for the bicycle.

\n
[3]
\n
a.
\n
\n

Find the value of the bicycle during the 5th year. Give your answer to two decimal places.

\n
[3]
\n
b.
\n
\n

Calculate, in years, when the bicycle value will be less than 50 USD.

\n
[2]
\n
c.
\n
\n

Find the total amount John has paid to insure his bicycle for the first 5 years.

\n
[3]
\n
d.
\n
\n

John purchased the bicycle in 2008.

\n

Justify why John should not insure his bicycle in 2019.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

1.042 × 880 × 1.25  OR  (880 + 0.042 × 880) × 1.25      (M1)(M1)

\n

Note: Award (M1) for multiplying 880 by 1.042 and (M1) for multiplying 880 by 1.25.

\n

1150 (CAD)  (1146.20 (CAD))      (A1)(G2)

\n

Note: Accept 1146.2 (CAD)

\n

[3 marks]

\n
a.
\n
\n

\n\n\n704\n\n\n880\n\n\n  OR  \n\n\n563.20\n\n\n704\n\n\n      (M1)

\n

Note: Award (M1) for correctly dividing sequential terms to find the common ratio, or 0.8 seen.

\n

880(0.8)5−1      (M1)

\n

Note: Award (M1) for correct substitution into geometric sequence formula.

\n

360.45 (USD)      (A1)(G3)

\n

Note: Do not award the final (A1) if the answer is not correct to 2 decimal places. Award at most (M0)(M1)(A0) if \nr\n=\n1.25\n.

\n

[3 marks]

\n
b.
\n
\n

\n880\n\n\n\n(\n\n0.8\n\n)\n\n\nn\n\n1\n\n\n\n<\n50\n     (M1)

\n

Note: Award (M1) for correct substitution into geometric sequence formula and (in)equating to 50. Accept weak or strict inequalities. Accept an equation. Follow through from their common ratio in part (b). Accept a sketch of their GP with \ny\n=\n50\n as a valid method.

\n

OR

\n

\n\n\nu\n\n13\n\n\n\n=\n60.473\n  AND  \n\n\nu\n\n14\n\n\n\n=\n48.379\n      (M1)

\n

Note: Award (M1) for their \n\n\nu\n\n13\n\n\n\n and \n\n\nu\n\n14\n\n\n\n both seen. If the student states \n\n\nu\n\n14\n\n\n\n=\n48.379\n<\n50\n, without \n\n\nu\n\n13\n\n\n\n=\n60.473\n seen, this is not sufficient to award (M1).

\n

14 or “14th year” or “after the 13th year”     (A1)(ft)(G2)

\n

Note: The context of the question requires the final answer to be an integer. Award at most (M1)(A0) for a final answer of 13.9 years. Follow through from their 0.8 in part (b).

\n

[2 marks]

\n
c.
\n
\n

\n\n5\n2\n\n\n(\n\n\n(\n\n2\n×\n120\n\n)\n\n+\n\n(\n\n\n3.5\n\n(\n\n5\n\n1\n\n)\n\n\n)\n\n\n)\n\n    (M1)(A1)

\n

Note: Award (M1) for substitution into arithmetic series formula, (A1) for correct substitution.

\n

565 (USD)    (A1)(G2)

\n

[3 marks]

\n
d.
\n
\n

2019 is the 12th year/term        (M1)

\n

Note: Award (M1) for 12 seen.

\n

75.59 (value of bicycle)  AND  81.5 (cost of insurance policy)       (A1)(ft)

\n

Note: Award (A1) for both sequences’ 12th term seen. The value of the bicycle will follow through from their common ratio in part (b). Do not award (M0)(A1).

\n

the cost of the insurance policy is greater than the value of the bicycle      (R1)(ft)

\n

Note: Award (R1)(ft) for a reason consistent with their cost of insurance policy and their value of the bicycle. Follow through within this part. Award (R0) if the correct values are not explicitly seen. Accept the following contextualized reasons: “the insurance is not worth it\", \"the values are too close\", \"insurance is as much as the value of the bike\", but only if their cost of insurance is greater than the value of the bicycle.

\n

OR

\n

75.59 < 81.5       (R1)(ft)

\n

Note: Award (R1)(ft) for a correct numerical comparison showing their cost of insurance policy is greater than their value of the bicycle. Follow through within this part.

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "19M.2.SL.TZ1.T_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Use the method of mathematical induction to prove that \n\n\n4\nn\n\n\n+\n15\nn\n\n1\n is divisible by 9 for \nn\n\n\n\n\nZ\n\n+\n\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

let \nP\n(\nn\n)\n be the proposition that \n\n\n4\nn\n\n\n+\n15\nn\n\n1\n is divisible by 9

\n

showing true for \nn\n=\n1\n     A1

\n

ie\n\n\n\n\n\nfor \nn\n=\n1\n,\n\n \n\n\n\n4\n1\n\n\n+\n15\n×\n1\n\n1\n=\n18\n

\n

which is divisible by 9, therefore \nP\n(\n1\n)\n is true

\n

assume \nP\n(\nk\n)\n is true so \n\n\n4\nk\n\n\n+\n15\nk\n\n1\n=\n9\nA\n,\n\n \n\n(\nA\n\n\n\n\nZ\n\n+\n\n\n)\n     M1

\n

 

\n

Note:     Only award M1 if “truth assumed” or equivalent.

\n

 

\n

consider \n\n\n4\n\nk\n+\n1\n\n\n\n+\n15\n(\nk\n+\n1\n)\n\n1\n

\n

\n=\n4\n×\n\n\n4\nk\n\n\n+\n15\nk\n+\n14\n

\n

\n=\n4\n(\n9\nA\n\n15\nk\n+\n1\n)\n+\n15\nk\n+\n14\n     M1

\n

\n=\n4\n×\n9\nA\n\n45\nk\n+\n18\n     A1

\n

\n=\n9\n(\n4\nA\n\n5\nk\n+\n2\n)\n which is divisible by 9     R1

\n

 

\n

Note:     Award R1 for either the expression or the statement above.

\n

 

\n

since \nP\n(\n1\n)\n is true and \nP\n(\nk\n)\n true implies \nP\n(\nk\n+\n1\n)\n is true, therefore (by the principle of mathematical induction) \nP\n(\nn\n)\n is true for \nn\n\n\n\n\nZ\n\n+\n\n\n     R1

\n

 

\n

Note:     Only award the final R1 if the 2 M1s have been awarded.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.AHL.TZ1.H_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

Let \ny\n=\n\narccos\n\n\n(\n\n\nx\n2\n\n\n)\n\n

\n
\n

Find \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n.

\n
[2]
\n
a.
\n
\n

Find \n\n\n0\n1\n\n\n\narccos\n\n\n(\n\n\nx\n2\n\n\n)\n\n\nd\n\nx\n\n.

\n
[7]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ny\n=\n\narccos\n\n\n(\n\n\nx\n2\n\n\n)\n\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n1\n\n2\n\n1\n\n\n\n\n\n(\n\n\nx\n2\n\n\n)\n\n\n2\n\n\n\n\n\n\n(\n\n=\n\n\n1\n\n\n4\n\n\n\nx\n2\n\n\n\n\n\n\n)\n\n    M1A1

\n

Note: M1 is for use of the chain rule.

\n

[2 marks]

\n
a.
\n
\n

attempt at integration by parts     M1

\n

\nu\n=\n\narccos\n\n\n(\n\n\nx\n2\n\n\n)\n\n\n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n\n\n1\n\n\n4\n\n\n\nx\n2\n\n\n\n\n\n

\n

\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n1\n\nv\n=\nx\n     (A1)

\n

\n\n\n0\n1\n\n\n\narccos\n\n\n(\n\n\nx\n2\n\n\n)\n\n\nd\n\nx\n\n=\n\n\n[\n\nx\n\n\n\narccos\n\n\n(\n\n\nx\n2\n\n\n)\n\n\n]\n\n0\n1\n\n+\n\n\n0\n1\n\n\n\n1\n\n\n4\n\n\n\nx\n2\n\n\n\n\n\n\nd\nx\n      A1

\n

using integration by substitution or inspection      (M1)

\n

\n\n\n[\n\nx\n\n\n\narccos\n\n\n(\n\n\nx\n2\n\n\n)\n\n\n]\n\n0\n1\n\n+\n\n\n[\n\n\n\n\n\n\n(\n\n4\n\n\n\nx\n2\n\n\n\n)\n\n\n\n\n1\n2\n\n\n\n\n\n]\n\n0\n1\n\n      A1

\n

Note: Award A1 for \n\n\n\n\n\n\n(\n\n4\n\n\n\nx\n2\n\n\n\n)\n\n\n\n\n1\n2\n\n\n\n\n\n or equivalent.

\n

Note: Condone lack of limits to this point.

\n

attempt to substitute limits into their integral     M1

\n

\n=\n\nπ\n3\n\n\n\n3\n\n+\n2\n     A1

\n

[7 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.AHL.TZ1.H_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Consider the function \n\n\nf\nn\n\n\n(\nx\n)\n=\n(\ncos\n\n2\nx\n)\n(\ncos\n\n4\nx\n)\n\n(\ncos\n\n\n\n2\nn\n\n\nx\n)\n,\n\n \n\nn\n\n\n\n\nZ\n\n+\n\n\n.

\n
\n

Determine whether f n is an odd or even function, justifying your answer.

\n
[2]
\n
a.
\n
\n

By using mathematical induction, prove that

\n

f n ( x ) = sin 2 n + 1 x 2 n sin 2 x ,   x m π 2 where m Z .

\n
[8]
\n
b.
\n
\n

Hence or otherwise, find an expression for the derivative of f n ( x ) with respect to x .

\n
[3]
\n
c.
\n
\n

Show that, for n > 1 , the equation of the tangent to the curve y = f n ( x ) at x = π 4 is 4 x 2 y π = 0 .

\n
[8]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

even function     A1

\n

since cos k x = cos ( k x ) and f n ( x ) is a product of even functions     R1

\n

OR

\n

even function     A1

\n

since ( cos 2 x ) ( cos 4 x ) = ( cos ( 2 x ) ) ( cos ( 4 x ) )     R1

\n

 

\n

Note:     Do not award A0R1.

\n

 

\n

[2 marks]

\n
a.
\n
\n

consider the case n = 1

\n

sin 4 x 2 sin 2 x = 2 sin 2 x cos 2 x 2 sin 2 x = cos 2 x     M1

\n

hence true for n = 1     R1

\n

assume true for n = k , ie, ( cos 2 x ) ( cos 4 x ) ( cos 2 k x ) = sin 2 k + 1 x 2 k sin 2 x     M1

\n

 

\n

Note:     Do not award M1 for “let n = k ” or “assume n = k ” or equivalent.

\n

 

\n

consider n = k + 1 :

\n

f k + 1 ( x ) = f k ( x ) ( cos 2 k + 1 x )     (M1)

\n

= sin 2 k + 1 x 2 k sin 2 x cos 2 k + 1 x     A1

\n

= 2 sin 2 k + 1 x cos 2 k + 1 x 2 k + 1 sin 2 x     A1

\n

= sin 2 k + 2 x 2 k + 1 sin 2 x     A1

\n

so n = 1 true and n = k true n = k + 1 true. Hence true for all n Z +     R1

\n

 

\n

Note:     To obtain the final R1, all the previous M marks must have been awarded.

\n

 

\n

[8 marks]

\n
b.
\n
\n

attempt to use f = v u u v v 2 (or correct product rule)     M1

\n

f n ( x ) = ( 2 n sin 2 x ) ( 2 n + 1 cos 2 n + 1 x ) ( sin 2 n + 1 x ) ( 2 n + 1 cos 2 x ) ( 2 n sin 2 x ) 2     A1A1

\n

 

\n

Note:     Award A1 for correct numerator and A1 for correct denominator.

\n

 

\n

[3 marks]

\n
c.
\n
\n

f n ( π 4 ) = ( 2 n sin π 2 ) ( 2 n + 1 cos 2 n + 1 π 4 ) ( sin 2 n + 1 π 4 ) ( 2 n + 1 cos π 2 ) ( 2 n sin π 2 ) 2     (M1)(A1)

\n

f n ( π 4 ) = ( 2 n ) ( 2 n + 1 cos 2 n + 1 π 4 ) ( 2 n ) 2     (A1)

\n

= 2 cos 2 n + 1 π 4   ( = 2 cos 2 n 1 π )     A1

\n

f n ( π 4 ) = 2     A1

\n

f n ( π 4 ) = 0     A1

\n

 

\n

Note:     This A mark is independent from the previous marks.

\n

 

\n

y = 2 ( x π 4 )     M1A1

\n

4 x 2 y π = 0     AG

\n

[8 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17N.1.AHL.TZ0.H_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

An earth satellite moves in a path that can be described by the curve \n72.5\n\n\nx\n2\n\n\n+\n71.5\n\n\ny\n2\n\n\n=\n1\n where \nx\n=\nx\n(\nt\n)\n and \ny\n=\ny\n(\nt\n)\n are in thousands of kilometres and \nt\n is time in seconds.

\n

Given that \n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n=\n7.75\n×\n\n\n10\n\n\n5\n\n\n\n when \nx\n=\n3.2\n×\n\n\n10\n\n\n3\n\n\n\n, find the possible values of \n\n\n\nd\n\ny\n\n\n\nd\n\nt\n\n\n.

\n

Give your answers in standard form.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

substituting for \nx\n and attempting to solve for \ny\n (or vice versa)     (M1)

\n

\ny\n=\n(\n±\n)\n0.11821\n\n    (A1)

\n

EITHER

\n

\n145\nx\n+\n143\ny\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n\n \n\n\n(\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n\n145\nx\n\n\n143\ny\n\n\n\n)\n\n    M1A1

\n

OR

\n

\n145\nx\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n+\n143\ny\n\n\n\nd\n\ny\n\n\n\nd\n\nt\n\n\n=\n0\n    M1A1

\n

THEN

\n

attempting to find \n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n\n \n\n\n(\n\n\n\n\nd\n\ny\n\n\n\nd\n\nt\n\n\n=\n\n\n\n145\n(\n3.2\n×\n\n\n\n10\n\n\n\n3\n\n\n\n)\n\n\n143\n\n(\n\n(\n±\n)\n0.11821\n\n\n)\n\n\n\n×\n(\n7.75\n×\n\n\n\n10\n\n\n\n5\n\n\n\n)\n\n)\n\n     (M1)

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nt\n\n\n=\n±\n2.13\n×\n\n\n10\n\n\n6\n\n\n\n    A1

\n

 

\n

Note: Award all marks except the final A1 to candidates who do not consider ±.

\n

 

\n

METHOD 2

\n

\ny\n=\n(\n±\n)\n\n\n\n1\n\n72.5\n\n\nx\n2\n\n\n\n\n71.5\n\n\n\n    M1A1

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n(\n±\n)\n0.0274\n\n    (M1)(A1)

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nt\n\n\n=\n(\n±\n)\n0.0274\n\n×\n7.75\n×\n\n\n10\n\n\n5\n\n\n\n    (M1)

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nt\n\n\n=\n±\n2.13\n×\n\n\n10\n\n\n6\n\n\n\n    A1

\n

 

\n

Note: Award all marks except the final A1 to candidates who do not consider ±.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.2.AHL.TZ0.H_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Sara regularly flies from Geneva to London. She takes either a direct flight or a non-directflight that goes via Amsterdam.

\n

If she takes a direct flight, the probability that her baggage does not arrive in London is 0.01.
If she takes a non-direct flight the probability that her baggage arrives in London is 0.95.

\n

The probability that she takes a non-direct flight is 0.2.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/07\"

\n
\n

Complete the tree diagram.

\n
[3]
\n
a.
\n
\n

Find the probability that Sara’s baggage arrives in London.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"M17/5/MATSD/SP1/ENG/TZ1/07.a/M\"     (A1)(A1)(A1)     (C3)

\n

 

\n

 

\n

Note:     Award (A1) for each correct pair of probabilities.

\n

 

\n

[3 marks]

\n
a.
\n
\n

\n0.8\n×\n0.99\n+\n0.2\n×\n0.95\n     (A1)(ft)(M1)

\n

 

\n

Note:     Award (A1)(ft) for two correct products of probabilities taken from their diagram, (M1) for the addition of their products.

\n

 

\n

\n=\n0.982\n\n \n\n\n(\n\n98.2\n%\n,\n\n \n\n\n\n491\n\n\n500\n\n\n\n)\n\n     (A1)(ft)     (C3)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ1.T_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Find the coordinates of the points on the curve \n\n\ny\n3\n\n\n+\n3\nx\n\n\ny\n2\n\n\n\n\n\nx\n3\n\n\n=\n27\n at which \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt at implicit differentiation      M1

\n

\n3\n\n\ny\n2\n\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n+\n3\n\n\ny\n2\n\n\n+\n6\nx\ny\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n3\n\n\nx\n2\n\n\n=\n0\n      A1A1

\n

Note: Award A1 for the second & third terms, A1 for the first term, fourth term & RHS equal to zero.

\n

substitution of \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n      M1

\n

\n3\n\n\ny\n2\n\n\n\n3\n\n\nx\n2\n\n\n=\n0\n

\n

\n\ny\n=\n±\nx\n      A1

\n

substitute either variable into original equation       M1

\n

\ny\n=\nx\n\n\n\nx\n3\n\n\n=\n9\n\nx\n=\n\n9\n3\n\n   (or  \n\n\ny\n3\n\n\n=\n9\n\ny\n=\n\n9\n3\n\n)      A1

\n

\ny\n=\n\nx\n\n\n\nx\n3\n\n\n=\n27\n\nx\n=\n3\n   (or  \n\n\ny\n3\n\n\n=\n\n27\n\ny\n=\n\n3\n)      A1

\n

\n\n(\n\n\n9\n3\n\n\n,\n\n\n\n\n9\n3\n\n\n)\n\n , (3, −3)      A1

\n

[9 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ1.H_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

The folium of Descartes is a curve defined by the equation \n\n\nx\n3\n\n\n+\n\n\ny\n3\n\n\n\n3\nx\ny\n=\n0\n, shown in the following diagram.

\n

\"N17/5/MATHL/HP1/ENG/TZ0/07\"

\n

Determine the exact coordinates of the point P on the curve where the tangent line is parallel to the \ny\n-axis.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nx\n3\n\n\n+\n\n\ny\n3\n\n\n\n3\nx\ny\n=\n0\n

\n

\n3\n\n\nx\n2\n\n\n+\n3\n\n\ny\n2\n\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n3\nx\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n3\ny\n=\n0\n     M1A1

\n

 

\n

Note:     Differentiation wrt \ny\n is also acceptable.

\n

 

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n3\ny\n\n3\n\n\nx\n2\n\n\n\n\n3\n\n\ny\n2\n\n\n\n3\nx\n\n\n\n \n\n\n(\n\n=\n\n\ny\n\n\n\nx\n2\n\n\n\n\n\n\ny\n2\n\n\n\nx\n\n\n\n)\n\n     (A1)

\n

 

\n

Note:     All following marks may be awarded if the denominator is correct, but the numerator incorrect.

\n

 

\n

\n\n\ny\n2\n\n\n\nx\n=\n0\n     M1

\n

EITHER

\n

\nx\n=\n\n\ny\n2\n\n\n

\n

\n\n\ny\n6\n\n\n+\n\n\ny\n3\n\n\n\n3\n\n\ny\n3\n\n\n=\n0\n     M1A1

\n

\n\n\ny\n6\n\n\n\n2\n\n\ny\n3\n\n\n=\n0\n

\n

\n\n\ny\n3\n\n\n(\n\n\ny\n3\n\n\n\n2\n)\n=\n0\n

\n

\n(\ny\n\n0\n)\n\ny\n=\n\n2\n3\n\n     A1

\n

\nx\n=\n\n\n\n(\n\n\n2\n3\n\n\n)\n\n2\n\n\n\n \n\n\n(\n\n=\n\n4\n3\n\n\n)\n\n     A1

\n

OR

\n

\n\n\nx\n3\n\n\n+\nx\ny\n\n3\nx\ny\n=\n0\n     M1

\n

\nx\n(\n\n\nx\n2\n\n\n\n2\ny\n)\n=\n0\n

\n

\nx\n\n0\n\ny\n=\n\n\n\n\nx\n2\n\n\n\n2\n\n     A1

\n

\n\n\ny\n2\n\n\n=\n\n\n\n\nx\n4\n\n\n\n4\n\n

\n

\nx\n=\n\n\n\n\nx\n4\n\n\n\n4\n\n

\n

\nx\n(\n\n\nx\n3\n\n\n\n4\n)\n=\n0\n

\n

\n(\nx\n\n0\n)\n\nx\n=\n\n4\n3\n\n     A1

\n

\ny\n=\n\n\n\n\n\n\n(\n\n\n4\n3\n\n\n)\n\n\n2\n\n\n\n2\n\n=\n\n2\n3\n\n     A1

\n

[8 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.AHL.TZ0.H_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

A bag contains 5 red and 3 blue discs, all identical except for the colour. First, Priyanka takes a disc at random from the bag and then Jorgé takes a disc at random from the bag.

\n
\n

Complete the tree diagram.

\n

\n
[3]
\n
a.
\n
\n

Find the probability that Jorgé chooses a red disc.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

   (A1)(A1)(A1) (C3)

\n

Note: Award (A1) for each correct pair of branches.

\n

 

\n

[3 marks]

\n
a.
\n
\n

\n\n5\n8\n\n×\n\n4\n7\n\n+\n\n3\n8\n\n×\n\n5\n7\n\n      (A1)(ft)(M1)

\n

Note: Award (A1)(ft) for their two correct products from their tree diagram. Follow through from part (a), award (M1) for adding their two products. Award (M0) if additional products or terms are added.

\n

 

\n

\n\n5\n8\n\n   \n\n(\n\n\n\n35\n\n\n56\n\n\n,\n\n\n0.625\n,\n\n\n62.5\n\n\n\n\n\n)\n\n     (A1)(ft) (C3)

\n

Note: Follow through from their tree diagram, only if probabilities are [0,1].

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.1.SL.TZ0.T_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Prove by mathematical induction that \n\n(\n\n\n\n\n2\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n3\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n+\n\n(\n\n\n\n\n\nn\n\n1\n\n\n\n\n\n2\n\n\n\n\n)\n\n=\n\n(\n\n\n\n\nn\n\n\n\n\n3\n\n\n\n\n)\n\n, where \nn\n\n\nZ\n\n,\nn\n\n3\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n(\n\n\n\n\n2\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n3\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n+\n\n(\n\n\n\n\n\nn\n\n1\n\n\n\n\n\n2\n\n\n\n\n)\n\n=\n\n(\n\n\n\n\nn\n\n\n\n\n3\n\n\n\n\n)\n\n

\n

show true for \nn\n=\n3\n     (M1)

\n

\n\nLHS\n\n=\n\n(\n\n\n\n\n2\n\n\n\n\n2\n\n\n\n\n)\n\n=\n1\n \n\n\n\n \n\nRHS\n\n=\n\n(\n\n\n\n\n3\n\n\n\n\n3\n\n\n\n\n)\n\n=\n1\n     A1

\n

hence true for \nn\n=\n3\n

\n

assume true for \nn\n=\nk\n:\n\n(\n\n\n\n\n2\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n3\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n+\n\n(\n\n\n\n\n\nk\n\n1\n\n\n\n\n\n2\n\n\n\n\n)\n\n=\n\n(\n\n\n\n\nk\n\n\n\n\n3\n\n\n\n\n)\n\n     M1

\n

consider for \nn\n=\nk\n+\n1\n:\n\n(\n\n\n\n\n2\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n3\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n+\n\n(\n\n\n\n\n\nk\n\n1\n\n\n\n\n\n2\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\nk\n\n\n\n\n2\n\n\n\n\n)\n\n     (M1)

\n

\n=\n\n(\n\n\n\n\nk\n\n\n\n\n3\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\nk\n\n\n\n\n2\n\n\n\n\n)\n\n     A1

\n

\n=\n\n\nk\n!\n\n\n(\nk\n\n3\n)\n!\n3\n!\n\n\n+\n\n\nk\n!\n\n\n(\nk\n\n2\n)\n!\n2\n!\n\n\n\n\n\n\n(\n\n=\n\n\nk\n!\n\n\n3\n!\n\n\n\n[\n\n\n1\n\n(\nk\n\n3\n)\n!\n\n\n+\n\n3\n\n(\nk\n\n2\n)\n!\n\n\n\n]\n\n\n)\n\n or any correct expression with a visible common factor     (A1)

\n

\n=\n\n\nk\n!\n\n\n3\n!\n\n\n\n[\n\n\n\nk\n\n2\n+\n3\n\n\n(\nk\n\n2\n)\n!\n\n\n\n]\n\n or any correct expression with a common denominator     (A1)

\n

\n=\n\n\nk\n!\n\n\n3\n!\n\n\n\n[\n\n\n\nk\n+\n1\n\n\n(\nk\n\n2\n)\n!\n\n\n\n]\n\n

\n

 

\n

Note:     At least one of the above three lines or equivalent must be seen.

\n

 

\n

\n=\n\n\n(\nk\n+\n1\n)\n!\n\n\n3\n!\n(\nk\n\n2\n)\n!\n\n\n or equivalent     A1

\n

\n=\n\n(\n\n\n\n\n\nk\n+\n1\n\n\n\n\n\n3\n\n\n\n\n)\n\n

\n

Result is true for \nk\n=\n3\n. If result is true for \nk\n it is true for \nk\n+\n1\n. Hence result is true for all \nk\n\n3\n. Hence proved by induction.     R1

\n

 

\n

Note:     In order to award the R1 at least [5 marks] must have been awarded.

\n

 

\n

[9 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.AHL.TZ2.H_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

The price per kilogram of tomatoes, in euro, sold in various markets in a city is found to be normally distributed with a mean of 3.22 and a standard deviation of 0.84.

\n
\n

Find the price that is two standard deviations above the mean price.

\n
[1]
\n
a.ii.
\n
\n

Find the probability that the price of a kilogram of tomatoes, chosen at random, will be between 2.00 and 3.00 euro.

\n
[2]
\n
b.
\n
\n

To stimulate reasonable pricing, the city offers a free permit to the sellers whose price of a kilogram of tomatoes is in the lowest 20 %.

\n

Find the highest price that a seller can charge and still receive a free permit.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

4.90     (A1)   (C1)

\n

[1 mark]

\n
a.ii.
\n
\n

0.323  (0.323499…; 32.3 %)     (A2)   (C2)

\n

Note: If final answer is incorrect, (M1)(A0) may be awarded for correct shaded area shown on a sketch, below, or for a correct probability statement “P(2 ≤ \nX\n ≤ 3)” (accept other variables for \nX\n or “price” and strict inequalities).

\n

\n

[2 marks]

\n
b.
\n
\n

2.51  (2.51303…)       (A2)   (C2)

\n

Note: If final answer is incorrect, (M1)(A0) may be awarded for correct shaded area shown on a sketch, below, or for a correct probability statement “P(\nX\n\na\n) = 0.2” (accept other variables and strict inequalities).

\n

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_14", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

A right circular cone of radius \nr\n is inscribed in a sphere with centre O and radius \nR\n as shown in the following diagram. The perpendicular height of the cone is \nh\n, X denotes the centre of its base and B a point where the cone touches the sphere.

\n

\n
\n

Show that the volume of the cone may be expressed by \nV\n=\n\nπ\n3\n\n\n(\n\n2\nR\n\n\nh\n2\n\n\n\n\n\nh\n3\n\n\n\n)\n\n.

\n
[4]
\n
a.
\n
\n

Given that there is one inscribed cone having a maximum volume, show that the volume of this cone is \n\n\n32\nπ\n\n\nR\n3\n\n\n\n\n81\n\n\n.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to use Pythagoras in triangle OXB       M1

\n

\n\n\n\nr\n2\n\n\n=\n\n\nR\n2\n\n\n\n\n\n\n(\n\nh\n\nR\n\n)\n\n2\n\n\n     A1

\n

substitution of their \n\n\nr\n2\n\n\n into formula for volume of cone \nV\n=\n\n\nπ\n\n\nr\n2\n\n\nh\n\n3\n\n       M1

\n

\n=\n\n\nπ\nh\n\n3\n\n\n(\n\n\n\nR\n2\n\n\n\n\n\n\n\n(\n\nh\n\nR\n\n)\n\n\n2\n\n\n\n)\n\n

\n

\n=\n\n\nπ\nh\n\n3\n\n\n(\n\n\n\nR\n2\n\n\n\n\n(\n\n\n\nh\n2\n\n\n+\n\n\nR\n2\n\n\n\n2\nh\nR\n\n)\n\n\n)\n\n       A1

\n

Note: This A mark is independent and may be seen anywhere for the correct expansion of \n\n\n\n\n\n(\n\nh\n\nR\n\n)\n\n\n2\n\n\n\n.

\n

\n=\n\n\nπ\nh\n\n3\n\n\n(\n\n2\nh\nR\n\n\n\nh\n2\n\n\n\n)\n\n

\n

\n=\n\nπ\n3\n\n\n(\n\n2\nR\n\n\nh\n2\n\n\n\n\n\nh\n3\n\n\n\n)\n\n       AG

\n

[4 marks]

\n
a.
\n
\n

at max, \n\n\n\nd\n\nV\n\n\n\nd\n\nh\n\n\n=\n0\n       R1

\n

\n\n\n\nd\n\nV\n\n\n\nd\n\nh\n\n\n=\n\nπ\n3\n\n\n(\n\n4\nR\nh\n\n3\n\n\nh\n2\n\n\n\n)\n\n

\n

\n\n4\nR\nh\n=\n3\n\n\nh\n2\n\n\n

\n

\n\nh\n=\n\n\n4\nR\n\n3\n\n (since \nh\n\n0\n)     A1

\n

EITHER

\n

\n\n\nV\n\n\nmax\n\n\n\n\n=\n\nπ\n3\n\n\n(\n\n2\nR\n\n\nh\n2\n\n\n\n\n\nh\n3\n\n\n\n)\n\n from part (a)

\n

\n=\n\nπ\n3\n\n\n(\n\n2\nR\n\n\n\n\n(\n\n\n\n4\nR\n\n3\n\n\n)\n\n\n2\n\n\n\n\n\n\n\n(\n\n\n\n4\nR\n\n3\n\n\n)\n\n\n3\n\n\n\n)\n\n     A1

\n

\n=\n\nπ\n3\n\n\n(\n\n2\nR\n\n\n16\n\n\nR\n2\n\n\n\n9\n\n\n\n(\n\n\n\n64\n\n\nR\n3\n\n\n\n\n27\n\n\n\n)\n\n\n)\n\n     A1

\n

OR

\n

\n\n\nr\n2\n\n\n=\n\n\nR\n2\n\n\n\n\n\n\n(\n\n\n\n4\nR\n\n3\n\n\nR\n\n)\n\n2\n\n\n

\n

\n\n\nr\n2\n\n\n=\n\n\nR\n2\n\n\n\n\n\n\n\nR\n2\n\n\n\n9\n\n=\n\n\n8\n\n\nR\n2\n\n\n\n9\n\n     A1

\n

\n\n\n\nV\n\n\nmax\n\n\n\n\n=\n\n\nπ\n\n\nr\n2\n\n\n\n3\n\n\n(\n\n\n\n4\nR\n\n3\n\n\n)\n\n

\n

\n=\n\n\n4\nπ\nR\n\n9\n\n\n(\n\n\n\n8\n\n\nR\n2\n\n\n\n9\n\n\n)\n\n     A1

\n

THEN

\n

\n=\n\n\n32\nπ\n\n\nR\n3\n\n\n\n\n81\n\n\n       AG

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.AHL.TZ2.H_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-7-the-second-derivative" ] }, { "Question": "
\n

Solve the inequality \n\n\nx\n2\n\n\n>\n2\nx\n+\n1\n.

\n
[2]
\n
a.
\n
\n

Use mathematical induction to prove that \n\n\n2\n\nn\n+\n1\n\n\n\n>\n\n\nn\n2\n\n\n for \nn\n\n\nZ\n\n\nn\n\n3\n.

\n
[7]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nx\n<\n\n0.414\n,\n\n\nx\n>\n2.41\n     A1A1

\n

\n\n(\n\nx\n<\n1\n\n\n2\n\n,\n\n\nx\n>\n1\n+\n\n2\n\n\n)\n\n

\n

Note: Award A1 for −0.414, 2.41 and A1 for correct inequalities.

\n

[2 marks]

\n
a.
\n
\n

check for \nn\n=\n3\n,

\n

16 > 9 so true when \nn\n=\n3\n        A1

\n

assume true for \nn\n=\nk\n

\n

\n\n\n2\n\nk\n+\n1\n\n\n\n>\n\n\nk\n2\n\n\n       M1

\n

Note: Award M0 for statements such as “let \nn\n=\nk\n”.

\n

Note: Subsequent marks after this M1 are independent of this mark and can be awarded.

\n

prove true for \nn\n=\nk\n+\n1\n

\n

\n\n\n2\n\nk\n+\n2\n\n\n\n=\n2\n×\n\n\n2\n\nk\n+\n1\n\n\n\n

\n

       \n>\n2\n\n\nk\n2\n\n\n       M1

\n

       \n=\n\n\nk\n2\n\n\n+\n\n\nk\n2\n\n\n       (M1)

\n

       \n>\n\n\nk\n2\n\n\n+\n2\nk\n+\n1\n (from part (a))        A1

\n

      which is true for \nk\n ≥ 3        R1

\n

Note: Only award the A1 or the R1 if it is clear why. Alternate methods are possible.

\n

\n=\n\n\n\n(\n\nK\n+\n1\n\n)\n\n2\n\n\n

\n

hence if true for \nn\n=\nk\n true for \nn\n=\nk\n+\n1\n, true for \nn\n=\n3\n so true for all \nn\n ≥ 3        R1

\n

Note: Only award the final R1 provided at least three of the previous marks are awarded.

\n

[7 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.AHL.TZ1.H_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

Given that \n2\n\n\nx\n3\n\n\n\n3\nx\n+\n1\n can be expressed in the form \nA\nx\n\n(\n\n\n\nx\n2\n\n\n+\n1\n\n)\n\n+\nB\nx\n+\nC\n, find the values of the constants \nA\n\nB\n and \nC\n.

\n
[2]
\n
a.
\n
\n

Hence find \n\n\n\n\n2\n\n\nx\n3\n\n\n\n3\nx\n+\n1\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n\nd\n\nx\n.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n2\n\n\nx\n3\n\n\n\n3\nx\n+\n1\n=\nA\nx\n\n(\n\n\n\nx\n2\n\n\n+\n1\n\n)\n\n+\nB\nx\n+\nC\n

\n

\nA\n=\n2\n,\n\n\nC\n=\n1\n,\n     A1

\n

\nA\n+\nB\n=\n\n3\n\nB\n=\n\n5\n     A1

\n

[2 marks]

\n
a.
\n
\n

\n\n\n\n\n2\n\n\nx\n3\n\n\n\n3\nx\n+\n1\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n\nd\n\nx\n=\n\n\n\n(\n\n2\nx\n\n\n\n5\nx\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n+\n\n1\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n)\n\n\n\nd\n\nx\n      M1M1

\n

Note: Award M1 for dividing by \n\n(\n\n\n\nx\n2\n\n\n+\n1\n\n)\n\n to get \n2\nx\n, M1 for separating the \n5\nx\n and 1.

\n

\n=\n\n\nx\n2\n\n\n\n\n5\n2\n\n\nln\n\n\n(\n\n\n\nx\n2\n\n\n+\n1\n\n)\n\n+\n\narctan\n\n\nx\n\n(\n\n+\nc\n\n)\n\n     (M1)A1A1

\n

Note: Award (M1)A1 for integrating \n\n\n\n5\nx\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n, A1 for the other two terms.

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.AHL.TZ1.H_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

Rosewood College has 120 students. The students can join the sports club (\nS\n) and the music club (\nM\n).

\n

For a student chosen at random from these 120, the probability that they joined both clubs is \n\n1\n4\n\n and the probability that they joined the music club is\n\n1\n3\n\n.

\n

There are 20 students that did not join either club.

\n
\n

Complete the Venn diagram for these students.

\n

\"N17/5/MATSD/SP1/ENG/TZ0/07.a\"

\n
[2]
\n
a.
\n
\n

One of the students who joined the sports club is chosen at random. Find the probability that this student joined both clubs.

\n
[2]
\n
b.
\n
\n

Determine whether the events \nS\n and \nM\n are independent.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"N17/5/MATSD/SP1/ENG/TZ0/07.a/M\"     (A1)(A1)     (C2)

\n

 

\n

Note:     Award (A1) for 30 in correct area, (A1) for 60 and 10 in the correct areas.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n\n\n30\n\n\n90\n\n\n\n \n\n\n(\n\n\n1\n3\n\n,\n\n \n\n0.333333\n\n,\n\n \n\n33.3333\n\n%\n\n)\n\n     (A1)(ft)(A1)(ft)     (C2)

\n

 

\n

Note:     Award (A1)(ft) for correct numerator of 30, (A1)(ft) for correct denominator of 90. Follow through from their Venn diagram.

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n\nP\n\n(\nS\n)\n×\n\nP\n\n(\nM\n)\n=\n\n3\n4\n\n×\n\n1\n3\n\n=\n\n1\n4\n\n     (R1)

\n

 

\n

Note:     Award (R1) for multiplying their by \n\n1\n3\n\n.

\n

 

\n

therefore the events are independent \n\n(\n\n\nas P\n\n(\nS\n\nM\n)\n=\n\n1\n4\n\n\n)\n\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Award (R1)(A1)(ft) for an answer which is consistent with their Venn diagram.

\n

Do not award (R0)(A1)(ft).

\n

Do not award final (A1) if \n\nP\n\n(\nS\n)\n×\n\nP\n\n(\nM\n)\n is not calculated. Follow through from part (a).

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.1.SL.TZ0.T_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

On a work day, the probability that Mr Van Winkel wakes up early is \n\n4\n5\n\n.

\n

If he wakes up early, the probability that he is on time for work is \np\n.

\n

If he wakes up late, the probability that he is on time for work is \n\n1\n4\n\n.

\n
\n

The probability that Mr Van Winkel arrives on time for work is \n\n3\n5\n\n.

\n
\n

Complete the tree diagram below.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/12.a\"

\n
[2]
\n
a.
\n
\n

Find the value of \np\n.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"N16/5/MATSD/SP1/ENG/TZ0/12.a/M\"     (A1)(A1)     (C2)

\n

 

\n

Note:     Award (A1) for each correct pair of probabilities.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n\n4\n5\n\np\n+\n\n1\n5\n\n×\n\n1\n4\n\n=\n\n3\n5\n\n     (A1)(ft)(M1)(M1)

\n

 

\n

Note:     Award (A1)(ft) for two correct products from part (a), (M1) for adding their products, (M1) for equating the sum of any two probabilities to \n\n3\n5\n\n.

\n

 

\n

\n(\np\n=\n)\n\n \n\n\n\n11\n\n\n16\n\n\n\n \n\n(\n0.688\n,\n\n \n\n0.6875\n)\n    (A1)(ft)     (C4)

\n

 

\n

Note:     Award the final (A1)(ft) only if \n0\n\np\n\n1\n. Follow through from part (a).

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_12", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The Tower of Pisa is well known worldwide for how it leans.

\n

Giovanni visits the Tower and wants to investigate how much it is leaning. He draws a diagram showing a non-right triangle, ABC.

\n

On Giovanni’s diagram the length of AB is 56 m, the length of BC is 37 m, and angle ACB is 60°. AX is the perpendicular height from A to BC.

\n

\n
\n

Giovanni’s tourist guidebook says that the actual horizontal displacement of the Tower, BX, is 3.9 metres.

\n
\n

Use Giovanni’s diagram to show that angle ABC, the angle at which the Tower is leaning relative to the
horizontal, is 85° to the nearest degree.

\n
[5]
\n
a.i.
\n
\n

Use Giovanni's diagram to calculate the length of AX.

\n
[2]
\n
a.ii.
\n
\n

Use Giovanni's diagram to find the length of BX, the horizontal displacement of the Tower.

\n
[2]
\n
a.iii.
\n
\n

Find the percentage error on Giovanni’s diagram.

\n
[2]
\n
b.
\n
\n

Giovanni adds a point D to his diagram, such that BD = 45 m, and another triangle is formed.

\n

\n

Find the angle of elevation of A from D.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

\n\n\n\nsin BAC\n\n\n\n37\n\n\n=\n\n\n\nsin 60\n\n\n\n56\n\n\n    (M1)(A1)

\n

Note: Award (M1) for substituting the sine rule formula, (A1) for correct substitution.

\n

angle \n\nB\n\n\n\nA\n\n\n\n\n\nC\n\n = 34.9034…°    (A1)

\n

Note: Award (A0) if unrounded answer does not round to 35. Award (G2) if 34.9034… seen without working.

\n

angle \n\nA\n\n\n\nB\n\n\n\n\n\nC\n\n = 180 − (34.9034… + 60)     (M1)

\n

Note: Award (M1) for subtracting their angle BAC + 60 from 180.

\n

85.0965…°    (A1)

\n

85°     (AG)

\n

Note: Both the unrounded and rounded value must be seen for the final (A1) to be awarded. If the candidate rounds 34.9034...° to 35° while substituting to find angle \n\nA\n\n\n\nB\n\n\n\n\n\nC\n\n, the final (A1) can be awarded but only if both 34.9034...° and 35° are seen.
If 85 is used as part of the workings, award at most (M1)(A0)(A0)(M0)(A0)(AG). This is the reverse process and not accepted.

\n
a.i.
\n
\n

sin 85… × 56     (M1)

\n

= 55.8 (55.7869…) (m)     (A1)(G2)

\n

Note: Award (M1) for correct substitution in trigonometric ratio.

\n
a.ii.
\n
\n

\n\n\n\n\n56\n\n2\n\n\n\n55.7869\n\n\n\n2\n\n\n\n     (M1)

\n

Note: Award (M1) for correct substitution in the Pythagoras theorem formula. Follow through from part (a)(ii).

\n

OR

\n

cos(85) × 56     (M1)

\n

Note: Award (M1) for correct substitution in trigonometric ratio.

\n

= 4.88 (4.88072…) (m)     (A1)(ft)(G2)

\n

Note: Accept 4.73 (4.72863…) (m) from using their 3 s.f answer. Accept equivalent methods.

\n

[2 marks]

\n
a.iii.
\n
\n

\n\n|\n\n\n\n4.88\n\n3.9\n\n\n3.9\n\n\n\n|\n\n×\n100\n     (M1)

\n

Note: Award (M1) for correct substitution into the percentage error formula.

\n

= 25.1  (25.1282) (%)     (A1)(ft)(G2)

\n

Note: Follow through from part (a)(iii).

\n

[2 marks]

\n
b.
\n
\n

\n\nta\n\n\n\n\nn\n\n\n\n1\n\n\n\n\n(\n\n\n\n55.7869\n\n\n\n40.11927\n\n\n\n\n)\n\n     (A1)(ft)(M1)

\n

Note: Award (A1)(ft) for their 40.11927… seen. Award (M1) for correct substitution into trigonometric ratio.

\n

OR

\n

(37 − 4.88072…)2 + 55.7869…2

\n

(AC =) 64.3725…

\n

64.3726…2 + 82 − 2 × 8 × 64.3726… × cos120

\n

(AD =) 68.7226…

\n

\n\n\n\nsin 120\n\n\n\n68.7226\n\n\n\n=\n\n\n\nsin A\n\n\n\nD\n\n\n\n\n\nC\n\n\n\n64.3725\n\n\n\n    (A1)(ft)(M1)

\n

Note: Award (A1)(ft) for their correct values seen, (M1) for correct substitution into the sine formula.

\n

= 54.3°  (54.2781…°)     (A1)(ft)(G2)

\n

Note: Follow through from part (a). Accept equivalent methods.

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.SL.TZ2.T_5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A function \nf\n satisfies the conditions \nf\n\n(\n0\n)\n\n=\n\n4\n\nf\n\n(\n1\n)\n\n=\n0\n and its second derivative is \n\nf\n\n\n\n(\nx\n)\n\n=\n15\n\nx\n\n+\n\n1\n\n\n\n\n\n(\n\nx\n+\n1\n\n)\n\n\n2\n\n\n\n\n, \nx\n ≥ 0.

\n

Find \nf\n\n(\nx\n)\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nf\n\n\n\n(\nx\n)\n\n=\n\n\n\n(\n\n15\n\nx\n\n+\n\n1\n\n\n\n\n\n(\n\nx\n+\n1\n\n)\n\n\n2\n\n\n\n\n\n)\n\n\n\n\nd\n\nx\n=\n10\n\n\nx\n\n\n3\n2\n\n\n\n\n\n\n1\n\nx\n+\n1\n\n\n\n(\n\n+\nc\n\n)\n\n      (M1)A1A1

\n

Note: A1 for first term, A1 for second term. Withhold one A1 if extra terms are seen.

\n

 

\n

\nf\n\n(\nx\n)\n\n=\n\n\n\n(\n\n10\n\n\nx\n\n\n3\n2\n\n\n\n\n\n\n1\n\nx\n+\n1\n\n\n+\nc\n\n)\n\n\n\n\nd\n\nx\n=\n4\n\n\nx\n\n\n5\n2\n\n\n\n\n\n\nln\n\n\n(\n\nx\n+\n1\n\n)\n\n+\nc\nx\n+\nd\n     A1

\n

Note: Allow FT from incorrect \n\nf\n\n\n\n(\nx\n)\n\n if it is of the form \n\nf\n\n\n\n(\nx\n)\n\n=\nA\n\n\nx\n\n\n3\n2\n\n\n\n\n+\n\nB\n\nx\n+\n1\n\n\n+\nc\n.

\n

Accept \n\nln\n\n\n|\n\nx\n+\n1\n\n|\n\n.

\n

 

\n

attempt to use at least one boundary condition in their \nf\n\n(\nx\n)\n\n      (M1)

\n

\nx\n=\n0\n\ny\n=\n\n4\n

\n

⇒ \nd\n=\n\n4\n      A1

\n

\nx\n=\n1\n\ny\n=\n0\n

\n

⇒ \n0\n=\n4\n\n\nln\n\n\n2\n+\nc\n\n4\n

\n

⇒  \nc\n=\n\nln\n\n\n2\n\n(\n\n=\n0.693\n\n)\n\n      A1

\n

\nf\n\n(\nx\n)\n\n=\n4\n\n\nx\n\n\n5\n2\n\n\n\n\n\n\nln\n\n\n(\n\nx\n+\n1\n\n)\n\n+\nx\n\n\nln\n\n\n2\n\n4\n

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.2.AHL.TZ0.H_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

The region \nA\n is enclosed by the graph of \ny\n=\n2\narcsin\n\n(\nx\n\n1\n)\n\n\nπ\n4\n\n, the \ny\n-axis and the line \ny\n=\n\nπ\n4\n\n.

\n
\n

Write down a definite integral to represent the area of \nA\n.

\n
[4]
\n
a.
\n
\n

Calculate the area of \nA\n.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n2\narcsin\n\n(\nx\n\n1\n)\n\n\nπ\n4\n\n=\n\nπ\n4\n\n     (M1)

\n

\nx\n=\n1\n+\n\n1\n\n\n2\n\n\n\n\n\n\n(\n=\n1.707\n\n)\n     (A1)

\n

\n\n\n0\n\n1\n+\n\n1\n\n\n2\n\n\n\n\n\n\n\nπ\n4\n\n\n\n(\n\n2\narcsin\n\n\n(\n\nx\n\n1\n\n)\n\n\n\nπ\n4\n\n\n)\n\nd\nx\n\n   M1A1

\n

 

\n

Note:     Award M1 for an attempt to find the difference between two functions, A1 for all correct.

\n

 

\n

METHOD 2

\n

when \nx\n=\n0\n,\n\n \n\ny\n=\n\n\n\n5\nπ\n\n4\n\n\n\n\n(\n=\n\n3.93\n)\n     A1

\n

\nx\n=\n1\n+\nsin\n\n\n(\n\n\n\n4\ny\n+\nπ\n\n8\n\n\n)\n\n    M1A1

\n

 

\n

Note:     Award M1 for an attempt to find the inverse function.

\n

 

\n

\n\n\n\n\n\n\n5\nπ\n\n4\n\n\n\n\nπ\n4\n\n\n\n\n\n(\n\n1\n+\nsin\n\n\n(\n\n\n\n4\ny\n+\nπ\n\n8\n\n\n)\n\n\n)\n\n\nd\n\ny\n\n     A1

\n

METHOD 3

\n

\n\n\n0\n\n1.38...\n\n\n\n\n(\n\n2\narcsin\n\n\n(\n\nx\n\n1\n\n)\n\n\n\nπ\n4\n\n\n)\n\n\nd\n\nx\n\n\n|\n+\n\n\n\n\n0\n\n1.71...\n\n\n\n\nπ\n4\n\n\nd\n\nx\n\n\n\n\n1.38...\n\n\n1.71...\n\n\n\n\n(\n\n2\narcsin\n\n\n(\n\nx\n\n1\n\n)\n\n\n\nπ\n4\n\n\n)\n\nd\nx\n\n\n    M1A1A1A1

\n

 

\n

Note:     Award M1 for considering the area below the \nx\n-axis and above the \nx\n-axis and A1 for each correct integral.

\n

 

\n

[4 marks]

\n
a.
\n
\n

\n\narea\n\n=\n3.30\n\n (square units)\n\n     A2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.AHL.TZ1.H_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-11-definite-integrals-areas-under-curve-onto-x-axis-and-areas-between-curves" ] }, { "Question": "
\n

Use the principle of mathematical induction to prove that

\n

\n1\n+\n2\n\n(\n\n\n1\n2\n\n\n)\n\n+\n3\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n2\n\n\n+\n4\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n3\n\n\n+\n\n\n\n+\nn\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n\nn\n\n1\n\n\n\n=\n4\n\n\n\nn\n+\n2\n\n\n\n\n2\n\nn\n\n1\n\n\n\n\n\n, where \nn\n\n\n\n\nZ\n\n+\n\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

if \nn\n=\n1\n

\n

\n\nLHS\n\n=\n1\n\n\n;\n\n\n\n\nRHS\n\n=\n4\n\n\n3\n\n\n\n2\n0\n\n\n\n\n=\n4\n\n3\n=\n1\n     M1

\n

hence true for \nn\n=\n1\n

\n

assume true for \nn\n=\nk\n     M1

\n

Note: Assumption of truth must be present. Following marks are not dependent on the first two M1 marks.

\n

so \n1\n+\n2\n\n(\n\n\n1\n2\n\n\n)\n\n+\n3\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n2\n\n\n+\n4\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n3\n\n\n+\n\n\n\n+\nk\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n\nk\n\n1\n\n\n\n=\n4\n\n\n\nk\n+\n2\n\n\n\n\n2\n\nk\n\n1\n\n\n\n\n\n

\n

if \nn\n=\nk\n+\n1\n

\n

\n1\n+\n2\n\n(\n\n\n1\n2\n\n\n)\n\n+\n3\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n2\n\n\n+\n4\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n3\n\n\n+\n\n\n\n+\nk\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n\nk\n\n1\n\n\n\n+\n\n(\n\nk\n+\n1\n\n)\n\n\n\n\n(\n\n\n1\n2\n\n\n)\n\nk\n\n\n

\n

\n=\n4\n\n\n\nk\n+\n2\n\n\n\n\n2\n\nk\n\n1\n\n\n\n\n\n+\n\n(\n\nk\n+\n1\n\n)\n\n\n\n\n(\n\n\n1\n2\n\n\n)\n\nk\n\n\n      M1A1

\n

finding a common denominator for the two fractions      M1

\n

\n=\n4\n\n\n\n2\n\n(\n\nk\n+\n2\n\n)\n\n\n\n\n\n2\nk\n\n\n\n\n+\n\n\nk\n+\n1\n\n\n\n\n2\nk\n\n\n\n\n

\n

\n=\n4\n\n\n\n2\n\n(\n\nk\n+\n2\n\n)\n\n\n\n(\n\nk\n+\n1\n\n)\n\n\n\n\n\n2\nk\n\n\n\n\n=\n4\n\n\n\nk\n+\n3\n\n\n\n\n2\nk\n\n\n\n\n\n(\n\n=\n4\n\n\n\n\n(\n\nk\n+\n1\n\n)\n\n+\n2\n\n\n\n\n2\n\n\n(\n\nk\n+\n1\n\n)\n\n\n1\n\n\n\n\n\n\n)\n\n     A1

\n

hence if true for \nn\n=\nk\n then also true for \nn\n=\nk\n+\n1\n, as true for \nn\n=\n1\n, so true (for all \nn\n\n\n\n\nZ\n\n+\n\n\n)     R1

\n

Note: Award the final R1 only if the first four marks have been awarded.

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ1.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

A group of 60 sports enthusiasts visited the PyeongChang 2018 Winter Olympic games to watch a variety of sporting events.

\n

The most popular sports were snowboarding (S), figure skating (F) and ice hockey (H).

\n

For this group of 60 people:

\n

4 did not watch any of the most popular sports,
x watched all three of the most popular sports,
9 watched snowboarding only,
11 watched figure skating only,
15 watched ice hockey only,
7 watched snowboarding and figure skating,
13 watched figure skating and ice hockey,
11 watched snowboarding and ice hockey.

\n
\n

Find the value of x.

\n
", "Markscheme": "
\n

4 + 9 + 11 + 15 + x + ( 7 x ) + ( 11 x ) + ( 13 x ) = 60      (M1)

\n

Note: Award (M1) for equating the sum of at least seven of the entries in their Venn diagram to 60.

\n

( x = ) 5      (A1)(ft) (C2)

\n

Note: Follow through from part (a), but only if answer is positive.

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.SL.TZ1.T_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Malthouse school opens at 08:00 every morning.

\n

The daily arrival times of the 500 students at Malthouse school follow a normal distribution. The mean arrival time is 52 minutes after the school opens and the standard deviation is 5 minutes.

\n
\n

Find the probability that a student, chosen at random arrives at least 60 minutes after the school opens.

\n
[2]
\n
a.i.
\n
\n

Find the probability that a student, chosen at random arrives between 45 minutes and 55 minutes after the school opens.

\n
[2]
\n
a.ii.
\n
\n

A second school, Mulberry Park, also opens at 08:00 every morning. The arrival times of the students at this school follows exactly the same distribution as Malthouse school.

\n

Given that, on one morning, 15 students arrive at least 60 minutes after the school opens, estimate the number of students at Mulberry Park school.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

0.0548  (0.054799…, 5.48%)     (A2) (C2)

\n

\n

[2 marks]

\n
a.i.
\n
\n

0.645  (0.6449900…, 64.5%)     (A2) (C2)

\n

\n

[2 marks]

\n
a.ii.
\n
\n

\n\n\n15\n\n\n0.0548\n\n\n     (M1)

\n

Note: Award (M1) for dividing 15 by their part (a)(i).

\n

Accept an equation of the form 15 = x × 0.0548 for (M1).

\n

274 (273.722…)      (A1)(ft) (C2)

\n

Note: Follow through from part (a)(i). Accept 273.

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ1.T_13", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Use mathematical induction to prove that \n\n\n\n(\n\n1\n\na\n\n)\n\nn\n\n\n>\n1\n\nn\na\n for \n\n{\n\nn\n\n\n:\n\n\nn\n\n\n\n\nZ\n\n+\n\n\n,\n\nn\n\n2\n\n}\n\n where \n0\n<\na\n<\n1\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

Let \n\n\n\nP\n\nn\n\n\n be the statement: \n\n\n\n(\n\n1\n\na\n\n)\n\nn\n\n\n>\n1\n\nn\na\n for some \n\nn\n\n\n\n\nZ\n\n+\n\n\n,\n\nn\n\n2\n\n where \n0\n<\na\n<\n1\n consider the case \nn\n=\n2\n\n:\n\n\n\n\n\n\n\n(\n\n1\n\na\n\n)\n\n2\n\n\n=\n1\n\n2\na\n+\n\n\na\n2\n\n\n     M1

\n

\n>\n1\n\n2\na\n because \n\n\na\n2\n\n\n<\n0\n. Therefore \n\n\n\nP\n\n2\n\n\n is true     R1

\n

assume \n\n\n\nP\n\nn\n\n\n is true for some \nn\n=\nk\n

\n

\n\n\n\n(\n\n1\n\na\n\n)\n\nk\n\n\n>\n1\n\nk\na\n     M1

\n

Note: Assumption of truth must be present. Following marks are not dependent on this M1.

\n

EITHER

\n

consider \n\n\n\n(\n\n1\n\na\n\n)\n\n\nk\n+\n1\n\n\n\n=\n\n(\n\n1\n\na\n\n)\n\n\n\n\n(\n\n1\n\na\n\n)\n\nk\n\n\n     M1

\n

\n>\n1\n\n\n(\n\nk\n+\n1\n\n)\n\na\n+\nk\n\n\na\n2\n\n\n      A1

\n

\n>\n1\n\n\n(\n\nk\n+\n1\n\n)\n\na\n\n\n\n\nP\n\n\nk\n+\n1\n\n\n\n is true (as \nk\n\n\na\n2\n\n\n>\n0\n)     R1

\n

OR

\n

multiply both sides by \n\n(\n\n1\n\na\n\n)\n\n (which is positive)      M1

\n

\n\n\n\n(\n\n1\n\na\n\n)\n\n\nk\n+\n1\n\n\n\n>\n\n(\n\n1\n\nk\na\n\n)\n\n\n(\n\n1\n\na\n\n)\n\n

\n

\n\n\n\n(\n\n1\n\na\n\n)\n\n\nk\n+\n1\n\n\n\n>\n1\n\n\n(\n\nk\n+\n1\n\n)\n\na\n+\nk\n\n\na\n2\n\n\n     A1

\n

\n\n\n\n(\n\n1\n\na\n\n)\n\n\nk\n+\n1\n\n\n\n>\n1\n\n\n(\n\nk\n+\n1\n\n)\n\na\n\n\n\n\nP\n\n\nk\n+\n1\n\n\n\n is true (as \nk\n\n\na\n2\n\n\n>\n0\n)     R1

\n

THEN

\n

\n\n\n\nP\n\n2\n\n\n is true \n\n\n\nP\n\nk\n\n\n is true \n\n\n\n\nP\n\n\nk\n+\n1\n\n\n\n is true so \n\n\n\nP\n\nn\n\n\n true for all \nn\n>\n2\n (or equivalent)      R1

\n

Note: Only award the last R1 if at least four of the previous marks are gained including the A1.

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.AHL.TZ2.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

Given that \n\n\n\n\n2\n\n2\n\n\nf\n\n(\nx\n)\n\n\nd\n\nx\n=\n10\n\n and \n\n\n0\n2\n\n\nf\n\n(\nx\n)\n\n\nd\n\nx\n=\n12\n\n, find

\n
\n

\n\n\n\n\n2\n\n0\n\n\n\n(\n\nf\n\n(\nx\n)\n\n\n + 2\n\n\n)\n\n\nd\n\nx\n\n.

\n
[4]
\n
a.
\n
\n

\n\n\n\n\n2\n\n0\n\n\nf\n\n(\n\nx\n\n + 2\n\n\n)\n\n\nd\n\nx\n\n.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\n\n2\n\n0\n\n\nf\n\n(\nx\n)\n\n\nd\n\nx\n=\n10\n\n\n12\n=\n\n2\n     (M1)(A1)

\n

\n\n\n\n\n2\n\n0\n\n\n\n2\n\nd\n\nx\n=\n\n[\n\n2\nx\n\n]\n\n\n\n\n2\n\n0\n\n=\n4\n     A1

\n

\n\n\n\n\n2\n\n0\n\n\n\n(\n\nf\n\n(\nx\n)\n\n\n + 2\n\n\n)\n\n\nd\n\nx\n\n=\n2\n     A1

\n

[4 marks]

\n
a.
\n
\n

\n\n\n\n\n2\n\n0\n\n\nf\n\n(\n\nx\n\n + 2\n\n\n)\n\n\nd\n\nx\n\n=\n\n\n0\n2\n\n\nf\n\n(\nx\n)\n\n\nd\n\nx\n\n    (M1)

\n

= 12     A1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.AHL.TZ1.H_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-11-definite-integrals-areas-under-curve-onto-x-axis-and-areas-between-curves" ] }, { "Question": "
\n

Abdallah owns a plot of land, near the river Nile, in the form of a quadrilateral ABCD.

\n

The lengths of the sides are \n\nAB\n\n=\n\n40 m, BC\n\n=\n\n115 m, CD\n\n=\n\n60 m, AD\n\n=\n\n84 m\n\n and angle \n\n\nB\n\n\nA\n^\n\n\nD\n\n\n=\n\n90\n\n\n.

\n

This information is shown on the diagram.

\n

\"N17/5/MATSD/SP2/ENG/TZ0/03\"

\n
\n

The formula that the ancient Egyptians used to estimate the area of a quadrilateral ABCD is

\n

\n\narea\n\n=\n\n\n(\n\nAB\n\n+\n\nCD\n\n)\n(\n\nAD\n\n+\n\nBC\n\n)\n\n4\n\n.

\n

Abdallah uses this formula to estimate the area of his plot of land.

\n
\n

Show that \n\nBD\n\n=\n93\n\n m\n\n correct to the nearest metre.

\n
[2]
\n
a.
\n
\n

Calculate angle \n\n\nB\n\n\nC\n^\n\n\nD\n\n\n.

\n
[3]
\n
b.
\n
\n

Find the area of ABCD.

\n
[4]
\n
c.
\n
\n

Calculate Abdallah’s estimate for the area.

\n
[2]
\n
d.i.
\n
\n

Find the percentage error in Abdallah’s estimate.

\n
[2]
\n
d.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nB\n\n\n\n\nD\n\n2\n\n\n=\n\n\n40\n2\n\n\n+\n\n\n84\n2\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into Pythagoras.

\n

Accept correct substitution into cosine rule.

\n

\n\nBD\n\n=\n93.0376\n\n     (A1)

\n

\n=\n93\n     (AG)

\n

 

\n

Note:     Both the rounded and unrounded value must be seen for the (A1) to be awarded.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\ncos\n\nC\n=\n\n\n\n\n\n115\n\n2\n\n\n+\n\n\n\n60\n\n2\n\n\n\n\n\n\n93\n\n2\n\n\n\n\n2\n×\n115\n×\n60\n\n\n\n \n\n(\n\n\n93\n2\n\n\n=\n\n\n115\n2\n\n\n+\n\n\n60\n2\n\n\n\n2\n×\n115\n×\n60\n×\ncos\n\nC\n)\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substitution into cosine formula, (A1) for correct substitutions.

\n

 

\n

\n=\n\n53.7\n\n\n\n \n\n(\n53.6679\n\n\n\n\n)\n     (A1)(G2)

\n

[3 marks]

\n
b.
\n
\n

\n\n1\n2\n\n(\n40\n)\n(\n84\n)\n+\n\n1\n2\n\n(\n115\n)\n(\n60\n)\nsin\n\n(\n53.6679\n\n)\n     (M1)(M1)(A1)(ft)

\n

 

\n

Note:     Award (M1) for correct substitution into right-angle triangle area. Award (M1) for substitution into area of triangle formula and (A1)(ft) for correct substitution.

\n

 

\n

\n=\n4460\n\n \n\n\n\n\nm\n\n2\n\n\n\n \n\n(\n4459.30\n\n\n \n\n\n\n\nm\n\n2\n\n\n)\n     (A1)(ft)(G3)

\n

 

\n

Notes:     Follow through from part (b).

\n

 

\n

[4 marks]

\n
c.
\n
\n

\n\n\n(\n40\n+\n60\n)\n(\n84\n+\n115\n)\n\n4\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution in the area formula used by ‘Ancient Egyptians’.

\n

 

\n

\n=\n4980\n\n \n\n\n\n\nm\n\n2\n\n\n\n \n\n(\n4975\n\n \n\n\n\n\nm\n\n2\n\n\n)\n     (A1)(G2)

\n

 

\n

 

\n

[2 marks]

\n
d.i.
\n
\n

\n\n|\n\n\n\n4975\n\n4459.30\n\n\n\n4459.30\n\n\n\n\n|\n\n×\n100\n     (M1)

\n

 

\n

Notes:     Award (M1) for correct substitution into percentage error formula.

\n

 

\n

\n=\n11.6\n\n \n\n(\n%\n)\n\n \n\n(\n11.5645\n\n)\n     (A1)(ft)(G2)

\n

 

\n

Notes:    Follow through from parts (c) and (d)(i).

\n

 

\n

[2 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "17N.2.SL.TZ0.T_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Consider the following Venn diagrams.

\n

\n
\n

Write down an expression, in set notation, for the shaded region represented by Diagram 1.

\n
[1]
\n
a.i.
\n
\n

Write down an expression, in set notation, for the shaded region represented by Diagram 2.

\n
[1]
\n
a.ii.
\n
\n

Write down an expression, in set notation, for the shaded region represented by Diagram 3.

\n
[2]
\n
a.iii.
\n
\n

Shade, on the Venn diagram, the region represented by the set  ( H I ) .

\n

\n

 

\n
[1]
\n
b.i.
\n
\n

Shade, on the Venn diagram, the region represented by the set J K .

\n

\n
[1]
\n
b.ii.
\n
", "Markscheme": "
\n

A'     (A1)

\n

Note: Accept alternative set notation for complement such as U − A.

\n

[1 mark]

\n
a.i.
\n
\n

C D   OR  D C      (A1)

\n

Note: Accept alternative set notation for complement.

\n

[1 mark]

\n
a.ii.
\n
\n

( E F ) G   OR   G ( E F )      (A2) (C4)

\n

Note: Accept equivalent answers, for example  ( E G ) ( F G ) .

\n

[2 marks]

\n

 

\n
a.iii.
\n
\n

     (A1)

\n

[1 mark]

\n
b.i.
\n
\n

(A1) (C2)
[1 mark]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18M.1.SL.TZ2.T_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Use mathematical induction to prove that \n\n\n\nr\n=\n1\n\nn\n\n\nr\n\n(\n\nr\n\n!\n\n\n)\n\n\n=\n\n(\n\nn\n+\n1\n\n)\n\n\n!\n\n\n1\n, for \nn\n\n\n\n\nZ\n\n+\n\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

consider \nn\n=\n1\n.  \n1\n\n(\n\n1\n\n!\n\n\n)\n\n=\n1\n and \n2\n\n!\n\n\n1\n=\n1\n  therefore true for \nn\n=\n1\n      R1

\n

Note: There must be evidence that \nn\n=\n1\n has been substituted into both expressions, or an expression such LHS=RHS=1 is used. “therefore true for \nn\n=\n1\n” or an equivalent statement must be seen.

\n

 

\n

assume true for \nn\n=\nk\n, (so that \n\n\n\nr\n=\n1\n\nk\n\n\nr\n\n(\n\nr\n\n!\n\n\n)\n\n\n=\n\n(\n\nk\n+\n1\n\n)\n\n\n!\n\n\n1\n)       M1

\n

Note: Assumption of truth must be present.

\n

 

\n

consider \nn\n=\nk\n+\n1\n

\n

\n\n\n\nr\n=\n1\n\n\nk\n+\n1\n\n\n\nr\n\n(\n\nr\n\n!\n\n\n)\n\n\n=\n\n\n\nr\n=\n1\n\nk\n\n\nr\n\n(\n\nr\n\n!\n\n\n)\n\n\n+\n\n(\n\nk\n+\n1\n\n)\n\n\n(\n\nk\n+\n1\n\n)\n\n\n!\n\n      (M1)

\n

\n\n = \n\n\n(\n\nk\n+\n1\n\n)\n\n\n!\n\n\n1\n+\n\n(\n\nk\n+\n1\n\n)\n\n\n(\n\nk\n+\n1\n\n)\n\n\n!\n\n      A1

\n

\n\n = \n\n\n(\n\nk\n+\n2\n\n)\n\n\n(\n\nk\n+\n1\n\n)\n\n\n!\n\n\n1\n       M1

\n

Note: M1 is for factorising \n\n(\n\nk\n+\n1\n\n)\n\n\n!\n\n

\n

 

\n

\n\n = \n\n\n(\n\nk\n+\n2\n\n)\n\n\n!\n\n\n1\n

\n

\n=\n\n(\n\n\n(\n\nk\n+\n1\n\n)\n\n+\n1\n\n)\n\n\n!\n\n\n1\n

\n

so if true for \nn\n=\nk\n, then also true for \nn\n=\nk\n+\n1\n, and as true for \nn\n=\n1\n then true for all \nn\n\n\n(\n\n\n\n\n\nZ\n\n+\n\n\n\n)\n\n      R1

\n

Note: Only award final R1 if all three method marks have been awarded.
Award R0 if the proof is developed from both LHS and RHS.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.1.AHL.TZ0.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\n\n\n(\n\nx\n\n1\n\n)\n\n2\n\n\n\nx\n ≥ 1 and the function \ng\n is defined by \ng\n\n(\nx\n)\n\n=\n\n\nx\n2\n\n\n+\n1\n\nx\n ≥ 0.

\n

The region \nR\n is bounded by the curves \ny\n=\nf\n\n(\nx\n)\n\n\ny\n=\ng\n\n(\nx\n)\n\n and the lines \ny\n=\n0\n\nx\n=\n0\n and \ny\n=\n9\n as shown on the following diagram.

\n

\n

The shape of a clay vase can be modelled by rotating the region \nR\n through 360˚ about the \ny\n-axis.

\n

Find the volume of clay used to make the vase.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

volume \n=\nπ\n\n\n\n0\n9\n\n\n\n\n(\n\n\n\ny\n\n\n1\n2\n\n\n\n\n+\n1\n\n)\n\n\n2\n\n\n\nd\n\ny\n\nπ\n\n\n1\n9\n\n\n\n(\n\ny\n\n1\n\n)\n\n\n\nd\n\ny\n      (M1)(M1)(M1)(A1)(A1)

\n

Note: Award (M1) for use of formula for rotating about \ny\n-axis, (M1) for finding at least one inverse, (M1) for subtracting volumes, (A1)(A1)for each correct expression, including limits.

\n

\n=\n268.6\n\n\n100.5\n\n\n(\n\n85.5\nπ\n\n32\nπ\n\n)\n\n

\n

\n=\n168\n\n(\n\n=\n53.5\nπ\n\n)\n\n       A2

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.2.AHL.TZ1.H_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-11-definite-integrals-areas-under-curve-onto-x-axis-and-areas-between-curves" ] }, { "Question": "
\n

A particle moves in a straight line such that at time \nt\n seconds \n(\nt\n\n0\n)\n, its velocity \nv\n, in \n\nm\n\n\n\n\ns\n\n\n\n1\n\n\n\n, is given by \nv\n=\n10\nt\n\n\n\ne\n\n\n\n2\nt\n\n\n\n. Find the exact distance travelled by the particle in the first half-second.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ns\n=\n\n\n0\n\n\n1\n2\n\n\n\n\n10\nt\n\n\n\ne\n\n\n\n2\nt\n\n\n\n\nd\n\nt\n\n

\n

attempt at integration by parts     M1

\n

\n=\n\n\n[\n\n\n5\nt\n\n\n\ne\n\n\n\n2\nt\n\n\n\n\n]\n\n0\n\n\n1\n2\n\n\n\n\n\n\n0\n\n\n1\n2\n\n\n\n\n\n5\n\n\n\ne\n\n\n\n2\nt\n\n\n\n\nd\n\nt\n\n     A1

\n

\n=\n\n\n[\n\n\n5\nt\n\n\n\ne\n\n\n\n2\nt\n\n\n\n\n\n5\n2\n\n\n\n\ne\n\n\n\n2\nt\n\n\n\n\n]\n\n0\n\n\n1\n2\n\n\n\n     (A1)

\n

 

\n

Note:     Condone absence of limits (or incorrect limits) and missing factor of 10 up to this point.

\n

 

\n

\ns\n=\n\n\n0\n\n\n1\n2\n\n\n\n\n10\nt\n\n\n\ne\n\n\n\n2\nt\n\n\n\n\nd\n\nt\n\n     (M1)

\n

\n=\n\n5\n\n\n\ne\n\n\n\n1\n\n\n\n+\n\n5\n2\n\n\n \n\n\n(\n\n=\n\n\n\n5\n\n\ne\n\n\n+\n\n5\n2\n\n\n)\n\n\n \n\n\n(\n\n=\n\n\n5\n\ne\n\n\n10\n\n\n2\n\ne\n\n\n\n\n)\n\n     A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.AHL.TZ0.H_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

Let S be the sum of the roots found in part (a).

\n
\n

Find the roots of  z 24 = 1 which satisfy the condition 0 < arg ( z ) < π 2 , expressing your answers in the form r e i θ , where r , θ R + .

\n
[5]
\n
a.
\n
\n

Show that Re S = Im S.

\n
[4]
\n
b.i.
\n
\n

By writing  π 12 as ( π 4 π 6 ) , find the value of cos  π 12 in the form a + b c , where a b and  c are integers to be determined.

\n
[3]
\n
b.ii.
\n
\n

Hence, or otherwise, show that S = 1 2 ( 1 + 2 ) ( 1 + 3 ) ( 1 + i ) .

\n
[4]
\n
b.iii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

( r ( cos θ + i sin θ ) ) 24 = 1 ( cos 0 + i sin 0 )

\n

use of De Moivre’s theorem       (M1)

\n

r 24 = 1 r = 1       (A1)

\n

24 θ = 2 π n θ = π n 12 ( n Z )       (A1)

\n

0 < arg ( z ) < π 2 n = 1, 2, 3, 4, 5

\n

z = e π i 12 or  e 2 π i 12 or  e 3 π i 12 or  e 4 π i 12 or  e 5 π i 12       A2

\n

Note: Award A1 if additional roots are given or if three correct roots are given with no incorrect (or additional) roots.

\n

 

\n

[5 marks]

\n
a.
\n
\n

Re S =  cos π 12 + cos 2 π 12 + cos 3 π 12 + cos 4 π 12 + cos 5 π 12

\n

Im S =  sin π 12 + sin 2 π 12 + sin 3 π 12 + sin 4 π 12 + sin 5 π 12       A1

\n

Note: Award A1 for both parts correct.

\n

but  sin 5 π 12 = cos π 12 ,   sin 4 π 12 = cos 2 π 12 ,   sin 3 π 12 = cos 3 π 12 ,   sin 2 π 12 = cos 4 π 12 and  sin π 12 = cos 5 π 12       M1A1

\n

⇒ Re S = Im S       AG

\n

Note: Accept a geometrical method.

\n

 

\n

[4 marks]

\n
b.i.
\n
\n

cos π 12 = cos ( π 4 π 6 ) = cos π 4 cos π 6 + sin π 4 sin π 6       M1A1

\n

= 2 2 3 2 + 2 2 1 2

\n

= 6 + 2 4        A1

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

 

\n

cos 5 π 12 = cos ( π 6 + π 4 ) = cos π 6 cos π 4 sin π 6 sin π 4       (M1)

\n

Note: Allow alternative methods eg  cos 5 π 12 = sin π 12 = sin ( π 4 π 6 ) .

\n

= 3 2 2 2 1 2 2 2 = 6 2 4       (A1)

\n

Re S =  cos π 12 + cos 2 π 12 + cos 3 π 12 + cos 4 π 12 + cos 5 π 12

\n

Re S =  2 + 6 4 + 3 2 + 2 2 + 1 2 + 6 2 4       A1

\n

= 1 2 ( 6 + 1 + 2 + 3 )       A1

\n

= 1 2 ( 1 + 2 ) ( 1 + 3 )

\n

S = Re(S)(1 + i) since Re S = Im S,      R1

\n

S =  1 2 ( 1 + 2 ) ( 1 + 3 ) ( 1 + i )       AG

\n

 

\n

[4 marks]

\n
b.iii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
", "question_id": "18N.1.AHL.TZ0.H_11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-10-compound-angle-identities" ] }, { "Question": "
\n

A point P moves in a straight line with velocity \nv\n ms−1 given by \nv\n\n(\nt\n)\n\n=\n\n\n\ne\n\n\n\nt\n\n\n\n\n8\n\n\nt\n2\n\n\n\n\n\ne\n\n\n\n2\nt\n\n\n\n at time t seconds, where t ≥ 0.

\n
\n

Determine the first time t1 at which P has zero velocity.

\n
[2]
\n
a.
\n
\n

Find an expression for the acceleration of P at time t.

\n
[2]
\n
b.i.
\n
\n

Find the value of the acceleration of P at time t1.

\n
[1]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to solve \nv\n\n(\nt\n)\n\n=\n0\n for t or equivalent     (M1)

\n

t1 = 0.441(s)     A1

\n

[2 marks]

\n
a.
\n
\n

\na\n\n(\nt\n)\n\n=\n\n\n\nd\n\nv\n\n\n\nd\n\nt\n\n\n=\n\n\n\n\ne\n\n\n\nt\n\n\n\n\n16\nt\n\n\n\ne\n\n\n\n2\nt\n\n\n\n+\n16\n\n\nt\n2\n\n\n\n\n\ne\n\n\n\n2\nt\n\n\n\n      M1A1

\n

Note: Award M1 for attempting to differentiate using the product rule.

\n

[2 marks]

\n
b.i.
\n
\n

\na\n\n(\n\n\n\nt\n1\n\n\n\n)\n\n=\n\n2.28\n (ms−2)      A1

\n

[1 mark]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18M.2.AHL.TZ2.H_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

Applicants for a job had to complete a mathematics test. The time they took to complete the test is normally distributed with a mean of 53 minutes and a standard deviation of 16.3. One of the applicants is chosen at random.

\n
\n

For 11% of the applicants it took longer than \nk\n minutes to complete the test.

\n
\n

There were 400 applicants for the job.

\n
\n

Find the probability that this applicant took at least 40 minutes to complete the test.

\n
[2]
\n
a.
\n
\n

Find the value of \nk\n.

\n
[2]
\n
b.
\n
\n

Estimate the number of applicants who completed the test in less than 25 minutes.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

0.787 (0.787433…, 78.7%)     (M1)(A1)     (C2)

\n

 

\n

Note:     Award (M1) for a correct probability statement, \n\nP\n\n(\nX\n>\n40\n)\n, or a correctly shaded normal distribution graph.

\n

 

\n

\"N17/5/MATSD/SP1/ENG/TZ0/13.a/M\"

\n

[2 marks]

\n
a.
\n
\n

73.0 (minutes) (72.9924…)     (M1)(A1)     (C2)

\n

 

\n

Note:     Award (M1) for a correct probability statement, \n\nP\n\n(\nX\n>\nk\n)\n=\n0.11\n, or a correctly shaded normal distribution graph.

\n

 

\n

\"N17/5/MATSD/SP1/ENG/TZ0/13.b/M\"

\n

[2 marks]

\n
b.
\n
\n

\n0.0423433\n\n×\n400\n     (M1)

\n

 

\n

Note:     Award (M1) for multiplying a probability by 400. Do not award (M1) for \n0.11\n×\n400\n.

\n

Use of a lower bound less than zero gives a probability of 0.0429172….

\n

\n=\n16\n     (A1)     (C2)

\n

 

\n

Notes:     Accept a final answer of 17. Do not accept a final answer of 18. Accept a non-integer final answer either 16.9 (16.9373…) from use of lower bound zero or 17.2 (17.1669…) from use of the default lower bound of \n\n\n\n10\n\n99\n\n\n\n.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.1.SL.TZ0.T_13", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

The following table shows the average body weight, \nx\n, and the average weight of the brain, \ny\n, of seven species of mammal. Both measured in kilograms (kg).

\n

\"M17/5/MATSD/SP2/ENG/TZ1/01\"

\n
\n

The average body weight of grey wolves is 36 kg.

\n
\n

In fact, the average weight of the brain of grey wolves is 0.120 kg.

\n
\n

The average body weight of mice is 0.023 kg.

\n
\n

Find the range of the average body weights for these seven species of mammal.

\n
[2]
\n
a.
\n
\n

For the data from these seven species calculate \nr\n, the Pearson’s product–moment correlation coefficient;

\n
[2]
\n
b.i.
\n
\n

For the data from these seven species describe the correlation between the average body weight and the average weight of the brain.

\n
[2]
\n
b.ii.
\n
\n

Write down the equation of the regression line \ny\n on \nx\n, in the form \ny\n=\nm\nx\n+\nc\n.

\n
[2]
\n
c.
\n
\n

Use your regression line to estimate the average weight of the brain of grey wolves.

\n
[2]
\n
d.
\n
\n

Find the percentage error in your estimate in part (d).

\n
[2]
\n
e.
\n
\n

State whether it is valid to use the regression line to estimate the average weight of the brain of mice. Give a reason for your answer.

\n
[2]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n529\n\n3\n     (M1)

\n

\n=\n526\n\n (kg)\n\n     (A1)(G2)

\n

[2 marks]

\n
a.
\n
\n

\n0.922\n\n \n\n(\n0.921857\n\n)\n     (G2)

\n

[2 marks]

\n
b.i.
\n
\n

(very) strong, positive     (A1)(ft)(A1)(ft)

\n

 

\n

Note:     Follow through from part (b)(i).

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

\ny\n=\n0.000986\nx\n+\n0.0923\n\n \n\n(\ny\n=\n0.000985837\n\nx\n+\n0.0923391\n\n)\n     (A1)(A1)

\n

 

\n

Note:     Award (A1) for \n0.000986\nx\n, (A1) for 0.0923.

\n

Award a maximum of (A1)(A0) if the answer is not an equation in the form \ny\n=\nm\nx\n+\nc\n.

\n

 

\n

[2 marks]

\n
c.
\n
\n

\n0.000985837\n\n(\n36\n)\n+\n0.0923391\n\n     (M1)

\n

 

\n

Note:     Award (M1) for substituting 36 into their equation.

\n

 

\n

\n0.128\n\n (kg) \n\n\n(\n\n0.127829\n\n\n (kg)\n\n\n)\n\n     (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from part (c). The final (A1) is awarded only if their answer is positive.

\n

 

\n

[2 marks]

\n
d.
\n
\n

\n\n|\n\n\n\n0.127829\n\n\n0.120\n\n\n0.120\n\n\n\n|\n\n×\n100\n     (M1)

\n

 

\n

Note:     Award (M1) for their correct substitution into percentage error formula.

\n

 

\n

\n6.52\n\n \n\n(\n%\n)\n\n \n\n\n(\n\n6.52442...\n\n \n\n(\n%\n)\n\n)\n\n     (A1)(ft)(G2)

\n

 

\n

Note: Follow through from part (d). Do not accept a negative answer.

\n

 

\n

[2 marks]

\n
e.
\n
\n

Not valid     (A1)

\n

the mouse is smaller/lighter/weighs less than the cat (lightest mammal)     (R1)

\n

OR

\n

as it would mean the mouse’s brain is heavier than the whole mouse     (R1)

\n

OR

\n

0.023 kg is outside the given data range.     (R1)

\n

OR

\n

Extrapolation     (R1)

\n

 

\n

Note:     Do not award (A1)(R0). Do not accept percentage error as a reason for validity.

\n

 

\n

[2 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "17M.2.SL.TZ1.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The mass of a certain type of Chilean corncob follows a normal distribution with a mean of 400 grams and a standard deviation of 50 grams.

\n
\n

A farmer labels one of these corncobs as premium if its mass is greater than \na\n grams. 25% of these corncobs are labelled as premium.

\n
\n

Write down the probability that the mass of one of these corncobs is greater than 400 grams.

\n
[1]
\n
a.
\n
\n

Find the value of \na\n.

\n
[2]
\n
b.
\n
\n

Estimate the interquartile range of the distribution.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n0.5\n\n \n\n\n(\n\n50\n%\n,\n\n \n\n\n1\n2\n\n\n)\n\n     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

\n\nP\n\n(\nX\n>\na\n)\n=\n0.25\n\n\n\n\nOR\n\n\n\n\n\nP\n\n(\nX\n<\na\n)\n=\n0.75\n     (M1)

\n

 

\n

Note:     Award (M1) for a sketch of approximate normal curve with a vertical line drawn to the right of the mean with the area to the right of this line shaded.

\n

 

\n

\na\n=\n434\n\n (g) \n\n\n(\n\n433.724\n\n\n (g)\n\n\n)\n\n     (A1)     (C2)

\n

[2 marks]

\n
b.
\n
\n

\n33.7244\n\n×\n2\n     (A1)(ft)(M1)

\n

 

\n

Note:     Award (A1)(ft) for \n33.7244\n\n\n \n\n(\n\nor \n\n433.7244\n\n\n \n\n\n\n \n\n400\n)\n seen, award (M1) for multiplying their 33.7244… by 2. Follow through from their answer to part (b).

\n

 

\n

OR

\n

\n434\n\n366.275\n\n     (A1)(ft)(M1)

\n

 

\n

Note:     Award (A1)(ft) for their \n366.275\n\n\n \n\n(\n366\n)\n seen, (M1) for difference between their answer to (b) and their 366.

\n

 

\n

OR

\n

\"M17/5/MATSD/SP1/ENG/TZ2/11.c/M\"     (A1)(ft)(M1)

\n

 

\n

Note:     Award (A1)(ft) for their \n366.275\n\n\n \n\n(\n366\n)\n seen. Award (M1) for correct symmetrical region indicated on labelled normal curve.

\n

 

\n

67.4 (g)     (A1)(ft)     (C3)

\n

 

\n

Note:     Accept an answer of 68 from use of rounded values. Follow through from part (b).

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_11", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

A particle moves along a straight line. Its displacement, \ns\n metres, at time \nt\n seconds is given by \ns\n=\nt\n+\ncos\n\n2\nt\n,\n\n \n\nt\n\n0\n. The first two times when the particle is at rest are denoted by \n\n\nt\n1\n\n\n and \n\n\nt\n2\n\n\n, where \n\n\nt\n1\n\n\n<\n\n\nt\n2\n\n\n.

\n
\n

Find \n\n\nt\n1\n\n\n and \n\n\nt\n2\n\n\n.

\n
[5]
\n
a.
\n
\n

Find the displacement of the particle when \nt\n=\n\n\nt\n1\n\n\n

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ns\n=\nt\n+\ncos\n\n2\nt\n

\n

\n\n\n\nd\n\ns\n\n\n\nd\n\nt\n\n\n=\n1\n\n2\nsin\n\n2\nt\n     M1A1

\n

\n=\n0\n     M1

\n

\n\nsin\n\n2\nt\n=\n\n1\n2\n\n

\n

\n\n\nt\n1\n\n\n=\n\nπ\n\n12\n\n\n(\ns\n)\n,\n\n \n\n\n\nt\n2\n\n\n=\n\n\n5\nπ\n\n\n12\n\n\n(\ns\n)\n     A1A1

\n

 

\n

Note:     Award A0A0 if answers are given in degrees.

\n

 

\n

[5 marks]

\n
a.
\n
\n

\ns\n=\n\nπ\n\n12\n\n\n+\ncos\n\n\nπ\n6\n\n\n\n\n\n(\n\ns\n=\n\nπ\n\n12\n\n\n+\n\n\n\n3\n\n\n2\n\n(\nm\n)\n\n)\n\n     A1A1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.AHL.TZ2.H_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

In a company it is found that 25 % of the employees encountered traffic on their way to work. From those who encountered traffic the probability of being late for work is 80 %.

\n

From those who did not encounter traffic, the probability of being late for work is 15 %.

\n

The tree diagram illustrates the information.

\n

\n
\n

The company investigates the different means of transport used by their employees in the past year to travel to work. It was found that the three most common means of transport used to travel to work were public transportation (P ), car (C ) and bicycle (B ).

\n

The company finds that 20 employees travelled by car, 28 travelled by bicycle and 19 travelled by public transportation in the last year.

\n

Some of the information is shown in the Venn diagram.

\n

\n
\n

There are 54 employees in the company.

\n
\n

Write down the value of a.

\n
[1]
\n
a.i.
\n
\n

Write down the value of b.

\n
[1]
\n
a.ii.
\n
\n

Use the tree diagram to find the probability that an employee encountered traffic and was late for work.

\n
[2]
\n
b.i.
\n
\n

Use the tree diagram to find the probability that an employee was late for work.

\n
[3]
\n
b.ii.
\n
\n

Use the tree diagram to find the probability that an employee encountered traffic given that they were late for work.

\n
[3]
\n
b.iii.
\n
\n

Find the value of x.

\n
[1]
\n
c.i.
\n
\n

Find the value of y.

\n
[1]
\n
c.ii.
\n
\n

Find the number of employees who, in the last year, did not travel to work by car, bicycle or public transportation.

\n
[2]
\n
d.
\n
\n

Find  n ( ( C B ) P ) .

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

a = 0.2     (A1)

\n

[1 mark]

\n
a.i.
\n
\n

b = 0.85     (A1)

\n

[1 mark]

\n
a.ii.
\n
\n

0.25 × 0.8     (M1)

\n

Note: Award (M1) for a correct product.

\n

= 0.2 ( 1 5 , 20 % )      (A1)(G2)

\n

[2 marks]

\n
b.i.
\n
\n

0.25 × 0.8 + 0.75 × 0.15     (A1)(ft)(M1)

\n

Note: Award (A1)(ft) for their (0.25 × 0.8) and (0.75 × 0.15), (M1) for adding two products.

\n

= 0.313 ( 0.3125 , 5 16 , 31.3 % )     (A1)(ft)(G3)

\n

Note: Award the final (A1)(ft) only if answer does not exceed 1. Follow through from part (b)(i).

\n

[3 marks]

\n

 

\n

 

\n

 

\n

 

\n
b.ii.
\n
\n

0.25 × 0.8 0.25 × 0.8 + 0.75 × 0.15     (A1)(ft)(A1)(ft)

\n

Note: Award (A1)(ft) for a correct numerator (their part (b)(i)), (A1)(ft) for a correct denominator (their part (b)(ii)). Follow through from parts (b)(i) and (b)(ii).

\n

= 0.64 ( 16 25 , 64 )      (A1)(ft)(G3)

\n

Note: Award final (A1)(ft) only if answer does not exceed 1.

\n

[3 marks]

\n
b.iii.
\n
\n

(x =) 3     (A1)

\n

[1 Mark]

\n
c.i.
\n
\n

(y =) 10     (A1)(ft)

\n

Note: Following through from part (c)(i) but only if their x is less than or equal to 13.

\n

[1 Mark]

\n
c.ii.
\n
\n

54 − (10 + 3 + 4 + 2 + 6 + 8 + 13)     (M1)

\n

Note: Award (M1) for subtracting their correct sum from 54. Follow through from their part (c).

\n

= 8      (A1)(ft)(G2)

\n

Note: Award (A1)(ft) only if their sum does not exceed 54. Follow through from their part (c).

\n

[2 marks]

\n
d.
\n
\n

6 + 8 + 13     (M1)

\n

Note: Award (M1) for summing 6, 8 and 13.

\n

27     (A1)(G2)

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.2.SL.TZ2.T_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Xavier, the parachutist, jumps out of a plane at a height of \nh\n metres above the ground. After free falling for 10 seconds his parachute opens. His velocity, \nv\n\n\nm\n\n\n\n\ns\n\n\n\n1\n\n\n\n, \nt\n seconds after jumping from the plane, can be modelled by the function

\n

\nv\n(\nt\n)\n=\n\n{\n\n\n\n\n\n9.8\nt\n\n,\n\n\n\n\n\n0\n\nt\n\n10\n\n\n\n\n\n\n\n\n98\n\n\n\n1\n+\n\n\n\n(\nt\n\n10\n)\n\n2\n\n\n\n\n\n,\n\n\n\n\nt\n>\n10\n\n\n\n\n\n\n\n

\n
\n

His velocity when he reaches the ground is \n2.8\n\n m\n\n\n\n\ns\n\n\n\n1\n\n\n\n.

\n
\n

Find his velocity when \nt\n=\n15\n.

\n
[2]
\n
a.
\n
\n

Calculate the vertical distance Xavier travelled in the first 10 seconds.

\n
[2]
\n
b.
\n
\n

Determine the value of \nh\n.

\n
[5]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nv\n(\n15\n)\n=\n\n\n98\n\n\n\n1\n+\n\n\n\n(\n15\n\n10\n)\n\n2\n\n\n\n\n\n     (M1)

\n

\nv\n(\n15\n)\n=\n19.2\n\n \n\n(\n\nm\n\n\n\n\ns\n\n\n\n1\n\n\n\n)\n     A1

\n

[2 marks]

\n
a.
\n
\n

\n\n\n0\n\n10\n\n\n\n9.8\nt\n\n\nd\n\nt\n\n    (M1)

\n

\n=\n490\n\n \n\n(\n\nm\n\n)\n     A1

\n

[2 marks]

\n
b.
\n
\n

\n\n\n98\n\n\n\n1\n+\n\n\n\n(\nt\n\n10\n)\n\n2\n\n\n\n\n\n=\n2.8\n     (M1)

\n

\nt\n=\n44.985\n\n\n \n\n(\n\ns\n\n)\n     A1

\n

\nh\n=\n490\n+\n\n\n\n10\n\n\n44.9...\n\n\n\n\n\n98\n\n\n\n1\n+\n\n\n\n(\nt\n\n10\n)\n\n2\n\n\n\n\n\n\nd\n\nt\n\n    (M1)(A1)

\n

\nh\n=\n906\n\n (m\n\n)\n     A1

\n

[5 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.AHL.TZ1.H_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

Let \nω\n be one of the non-real solutions of the equation \n\n\nz\n3\n\n\n=\n1\n.

\n
\n

Consider the complex numbers \np\n=\n1\n\n3\n\ni\n\n and \nq\n=\nx\n+\n(\n2\nx\n+\n1\n)\n\ni\n\n, where \nx\n\n\nR\n\n.

\n
\n

Determine the value of

\n

(i)     \n1\n+\nω\n+\n\n\nω\n2\n\n\n;

\n

(ii)     \n1\n+\nω\n\n*\n\n+\n\n(\nω\n\n*\n\n\n)\n2\n\n\n.

\n
[4]
\n
a.
\n
\n

Show that \n(\nω\n\n3\n\n\nω\n2\n\n\n)\n(\n\n\nω\n2\n\n\n\n3\nω\n)\n=\n13\n.

\n
[4]
\n
b.
\n
\n

Find the values of \nx\n that satisfy the equation \n\n|\np\n|\n\n=\n\n|\nq\n|\n\n.

\n
[5]
\n
c.
\n
\n

Solve the inequality \nRe\n\n(\np\nq\n)\n+\n8\n<\n\n\n\n(\n\nIm\n\n(\np\nq\n)\n\n)\n\n2\n\n\n.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(i)     METHOD 1

\n

\n1\n+\nω\n+\n\n\nω\n2\n\n\n=\n\n\n1\n\n\n\nω\n3\n\n\n\n\n1\n\nω\n\n\n=\n0\n    A1

\n

as \nω\n\n1\n     R1

\n

METHOD 2

\n

solutions of \n1\n\n\n\nω\n3\n\n\n=\n0\n are \nω\n=\n1\n,\n\n \n\nω\n\n = \n\n\n\n\n1\n±\n\n3\n\n\ni\n\n\n2\n\n     A1

\n

verification that the sum of these roots is 0     R1

\n

(ii)     \n1\n+\nω\n\n*\n\n+\n\n(\nω\n\n*\n\n\n)\n2\n\n\n=\n0\n     A2

\n

[4 marks]

\n
a.
\n
\n

\n(\nω\n\n3\n\n\nω\n2\n\n\n)\n(\n\n\nω\n2\n\n\n\n3\nω\n)\n=\n\n3\n\n\nω\n4\n\n\n+\n10\n\n\nω\n3\n\n\n\n3\n\n\nω\n2\n\n\n    M1A1

\n

EITHER

\n

\n=\n\n3\n\n\nω\n2\n\n\n(\n\n\nω\n2\n\n\n+\nω\n+\n1\n)\n+\n13\n\n\nω\n3\n\n\n    M1

\n

\n=\n\n3\n\n\nω\n2\n\n\n×\n0\n+\n13\n×\n1\n    A1

\n

OR

\n

\n=\n\n3\nω\n+\n10\n\n3\n\n\nω\n2\n\n\n=\n\n3\n(\n\n\nω\n2\n\n\n+\nω\n+\n1\n)\n+\n13\n    M1

\n

\n=\n\n3\n×\n0\n+\n13\n    A1

\n

OR

\n

substitution by \nω\n=\n\n\n\n1\n±\n\n3\n\n\ni\n\n\n2\n\n in any form     M1

\n

numerical values of each term seen     A1

\n

THEN

\n

\n=\n13\n    AG

\n

[4 marks]

\n
b.
\n
\n

\n\n|\np\n|\n\n=\n\n|\nq\n|\n\n\n\n\n\n1\n2\n\n\n+\n\n\n3\n2\n\n\n\n=\n\n\n\nx\n2\n\n\n+\n\n\n\n(\n2\nx\n+\n1\n)\n\n2\n\n\n\n    (M1)(A1)

\n

\n5\n\n\nx\n2\n\n\n+\n4\nx\n\n9\n=\n0\n    A1

\n

\n(\n5\nx\n+\n9\n)\n(\nx\n\n1\n)\n=\n0\n    (M1)

\n

\nx\n=\n1\n,\n\n \n\nx\n=\n\n\n9\n5\n\n    A1

\n

[5 marks]

\n
c.
\n
\n

\np\nq\n=\n(\n1\n\n3\n\ni\n\n)\n\n(\n\nx\n+\n(\n2\nx\n+\n1\n)\n\ni\n\n\n)\n\n=\n(\n7\nx\n+\n3\n)\n+\n(\n1\n\nx\n)\n\ni\n\n    M1A1

\n

\nRe\n\n(\np\nq\n)\n+\n8\n<\n\n\n\n(\n\nIm\n\n(\np\nq\n)\n\n)\n\n2\n\n\n\n(\n7\nx\n+\n3\n)\n+\n8\n<\n\n(\n1\n\nx\n\n)\n2\n\n\n    M1

\n

\n\n\n\nx\n2\n\n\n\n9\nx\n\n10\n>\n0\n    A1

\n

\n\n(\nx\n+\n1\n)\n(\nx\n\n10\n)\n>\n0\n    M1

\n

\nx\n<\n\n1\n,\n\n \n\nx\n>\n10\n    A1

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "16N.1.AHL.TZ0.H_12", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

A manufacturer produces 1500 boxes of breakfast cereal every day.

\n

The weights of these boxes are normally distributed with a mean of 502 grams and a standard deviation of 2 grams.

\n
\n

All boxes of cereal with a weight between 497.5 grams and 505 grams are sold. The manufacturer’s income from the sale of each box of cereal is $2.00.

\n
\n

The manufacturer recycles any box of cereal with a weight not between 497.5 grams and 505 grams. The manufacturer’s recycling cost is $0.16 per box.

\n
\n

A different manufacturer produces boxes of cereal with weights that are normally distributed with a mean of 350 grams and a standard deviation of 1.8 grams.

\n

This manufacturer sells all boxes of cereal that are above a minimum weight, \nw\n.

\n

They sell 97% of the cereal boxes produced.

\n
\n

Draw a diagram that shows this information.

\n
[2]
\n
a.
\n
\n

(i)     Find the probability that a box of cereal, chosen at random, is sold.

\n

(ii)     Calculate the manufacturer’s expected daily income from these sales.

\n
[4]
\n
b.
\n
\n

Calculate the manufacturer’s expected daily recycling cost.

\n
[2]
\n
c.
\n
\n

Calculate the value of \nw\n.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"N16/5/MATSD/SP2/ENG/TZ0/04.a/M\"

\n

(A1)(A1)

\n

 

\n

Notes:     Award (A1) for bell shape with mean of 502.

\n

Award (A1) for an indication of standard deviation eg 500 and 504.

\n

 

\n

[2 marks]

\n
a.
\n
\n

(i)     \n0.921\n\n \n\n(\n0.920968\n\n,\n\n \n\n92.0968\n\n%\n)\n     (G2)

\n

 

\n

Note:     Award (M1) for a diagram showing the correct shaded region.

\n

 

\n

(ii)     \n1500\n×\n2\n×\n0.920968\n\n     (M1)

\n

\n=\n\n \n\n(\n$\n)\n\n \n\n2760\n\n \n\n(\n2762.90\n\n)\n    (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from their answer to part (b)(i).

\n

 

\n

[4 marks]

\n
b.
\n
\n

\n1500\n×\n0.16\n×\n0.079031\n\n    (M1)

\n

 

\n

Notes:     Award (A1) for \n1500\n×\n0.16\n×\n\n their \n\n(\n1\n\n0.920968\n\n)\n.

\n

 

\n

OR

\n

\n(\n1500\n\n1381.45\n)\n×\n0.16\n    (M1)

\n

 

\n

Notes:     Award (M1) for \n(\n1500\n\n\ntheir \n\n1381.45\n)\n×\n0.16\n.

\n

 

\n

\n=\n(\n$\n)\n19.0\n\n (\n\n18.9676\n\n)\n    (A1)(ft)(G2)

\n

[2 marks]

\n
c.
\n
\n

\n347\n\n \n\n(\n\ngrams\n\n)\n\n \n\n(\n346.614\n\n)\n    (G3)

\n

 

\n

Notes:     Award (G2) for an answer that rounds to 346.

\n

Award (G1) for \n353.385\n\n seen without working (for finding the top 3%).

\n

 

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "16N.2.SL.TZ0.T_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

A particle moves along a horizontal line such that at time \nt\n seconds, \nt\n ≥ 0, its acceleration \na\n is given by \na\n = 2\nt\n − 1. When \nt\n = 6 , its displacement \ns\n from a fixed origin O is 18.25 m. When \nt\n = 15, its displacement from O is 922.75 m. Find an expression for \ns\n in terms of \nt\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to integrate \na\n to find \nv\n              M1

\n

\nv\n=\n\n\na\n\n\nd\n\nt\n=\n\n\n\n(\n\n2\nt\n\n1\n\n)\n\n\n\n\n\nd\n\nt\n

\n

\n=\n\n\nt\n2\n\n\n\nt\n+\nc\n      A1

\n

\ns\n=\n\n\nv\n\n\nd\n\nt\n=\n\n\n\n(\n\n\n\nt\n2\n\n\n\nt\n+\nc\n\n)\n\n\n\n\n\nd\n\nt\n

\n

\n=\n\n\n\n\nt\n3\n\n\n\n3\n\n\n\n\n\n\nt\n2\n\n\n\n2\n\n+\nc\nt\n+\nd\n      A1

\n

attempt at substitution of given values       (M1)

\n

at \nt\n=\n6\n\n,\n\n\n\n\n18.25\n=\n72\n\n18\n+\n6\nc\n+\nd\n

\n

at \nt\n=\n15\n\n,\n\n\n\n\n922.75\n=\n1125\n\n112.5\n+\n15\nc\n+\nd\n

\n

solve simultaneously:       (M1)

\n

\nc\n=\n\n6\n\n,\n\n\n\nd\n=\n0.25\n      A1

\n

\n\ns\n=\n\n\n\n\nt\n3\n\n\n\n3\n\n\n\n\n\n\nt\n2\n\n\n\n2\n\n+\n\n6\nt\n+\n\n1\n4\n\n

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.2.AHL.TZ2.H_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

By using the substitution \n\n\nx\n2\n\n\n=\n2\nsec\n\nθ\n, show that \n\n\n\n\n\nd\n\nx\n\n\nx\n\n\n\nx\n4\n\n\n\n4\n\n\n\n=\n\n1\n4\n\narccos\n\n\n(\n\n\n2\n\n\n\nx\n2\n\n\n\n\n\n)\n\n+\nc\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

EITHER

\n

\n\n\nx\n2\n\n\n=\n2\nsec\n\nθ\n

\n

\n2\nx\n\n\n\nd\n\nx\n\n\n\nd\n\nθ\n\n\n=\n2\nsec\n\nθ\ntan\n\nθ\n     M1A1

\n

\n\n\n\n\n\nd\n\nx\n\n\nx\n\n\n\nx\n4\n\n\n\n4\n\n\n\n\n

\n

\n=\n\n\n\n\nsec\n\nθ\ntan\n\nθ\n\nd\n\nθ\n\n\n2\nsec\n\nθ\n\n4\n\n\n\nsec\n\n2\n\n\nθ\n\n4\n\n\n\n\n     M1A1

\n

OR

\n

\nx\n=\n\n2\n\n\n(\nsec\n\nθ\n\n)\n\n\n1\n2\n\n\n\n\n\n \n\n\n(\n\n=\n\n2\n\n\n\n\n(\ncos\n\nθ\n)\n\n\n\n\n1\n2\n\n\n\n\n\n)\n\n

\n

\n\n\n\nd\n\nx\n\n\n\nd\n\nθ\n\n\n=\n\n\n\n2\n\n\n2\n\n\n(\nsec\n\nθ\n\n)\n\n\n1\n2\n\n\n\n\ntan\n\nθ\n\n \n\n\n(\n\n=\n\n\n\n2\n\n\n2\n\n\n\n\n(\ncos\n\nθ\n)\n\n\n\n\n3\n2\n\n\n\n\nsin\n\nθ\n\n)\n\n     M1A1

\n

\n\n\n\n\n\nd\n\nx\n\n\nx\n\n\n\nx\n4\n\n\n\n4\n\n\n\n\n

\n

\n=\n\n\n\n\n\n2\n\n\n\n\n(\nsec\n\nθ\n)\n\n\n\n1\n2\n\n\n\n\ntan\n\nθ\n\nd\n\nθ\n\n\n2\n\n2\n\n\n\n\n(\nsec\n\nθ\n)\n\n\n\n1\n2\n\n\n\n\n\n4\n\n\n\nsec\n\n2\n\n\nθ\n\n4\n\n\n\n\n \n\n\n(\n\n=\n\n\n\n\n\n2\n\n\n\n\n(\ncos\n\nθ\n)\n\n\n\n\n3\n2\n\n\n\n\nsin\n\nθ\n\nd\n\nθ\n\n\n2\n\n2\n\n\n\n\n(\ncos\n\nθ\n)\n\n\n\n\n1\n2\n\n\n\n\n\n4\n\n\n\nsec\n\n2\n\n\nθ\n\n4\n\n\n\n\n\n)\n\n\n     M1A1

\n

THEN

\n

\n=\n\n1\n2\n\n\n\n\n\ntan\n\nθ\n\nd\n\nθ\n\n\n2\ntan\n\nθ\n\n\n\n     (M1)

\n

\n=\n\n1\n4\n\n\n\n\nd\n\nθ\n\n

\n

\n=\n\nθ\n4\n\n+\nc\n     A1

\n

\n\n\nx\n2\n\n\n=\n2\nsec\n\nθ\n\ncos\n\nθ\n=\n\n2\n\n\n\nx\n2\n\n\n\n\n     M1

\n

 

\n

Note:     This M1 may be seen anywhere, including a sketch of an appropriate triangle.

\n

 

\n

so \n\nθ\n4\n\n+\nc\n=\n\n1\n4\n\narccos\n\n\n(\n\n\n2\n\n\n\nx\n2\n\n\n\n\n\n)\n\n+\nc\n     AG

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.2.AHL.TZ0.H_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

Using the substitution \nx\n=\ntan\n\nθ\n show that \n\n\n0\n1\n\n\n\n1\n\n\n\n\n\n(\n\n\n\nx\n2\n\n\n+\n1\n\n)\n\n\n2\n\n\n\n\n\nd\n\nx\n=\n\n\n\n0\n\n\nπ\n4\n\n\n\n\n\n\n\ncos\n\n2\n\n\nθ\n\nd\n\nθ\n\n.

\n
[4]
\n
a.
\n
\n

Hence find the value of \n\n\n0\n1\n\n\n\n1\n\n\n\n\n\n(\n\n\n\nx\n2\n\n\n+\n1\n\n)\n\n\n2\n\n\n\n\n\nd\n\nx\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

let \nx\n=\ntan\n\nθ\n

\n

\n\n\n\n\nd\n\nx\n\n\n\nd\n\nθ\n\n\n=\n\n\nsec\n2\n\n\nθ\n     (A1)

\n

\n\n\n\n1\n\n\n\n\n(\n\n\nx\n2\n\n\n+\n1\n)\n\n2\n\n\n\n\n\nd\n\nx\n=\n\n\n\n\n\n\n\nsec\n\n2\n\n\nθ\n\n\n\n\n\n(\n\n\n\ntan\n\n2\n\n\nθ\n+\n1\n)\n\n2\n\n\n\n\n\nd\n\nθ\n\n\n     M1

\n

 

\n

Note:     The method mark is for an attempt to substitute for both \nx\n and \n\nd\n\nx\n.

\n

 

\n

\n=\n\n\n\n1\n\n\n\n\nsec\n\n2\n\n\nθ\n\n\n\nd\n\nθ\n\n (or equivalent)     A1

\n

when \nx\n=\n0\n,\n\n \n\nθ\n=\n0\n and when \nx\n=\n1\n,\n\n \n\nθ\n=\n\nπ\n4\n\n     M1

\n

\n\n\n0\n\n\nπ\n4\n\n\n\n\n\n\n\ncos\n\n2\n\n\nθ\n\nd\n\nθ\n\n    AG

\n

[4 marks]

\n
a.
\n
\n

\n\n(\n\n\n\n0\n1\n\n\n\n1\n\n\n\n\n\n(\n\n\n\nx\n2\n\n\n+\n1\n\n)\n\n\n2\n\n\n\n\n\nd\n\nx\n\n=\n\n\n0\n\n\nπ\n4\n\n\n\n\n\n\n\ncos\n\n2\n\n\nθ\n\nd\n\nθ\n\n\n)\n\n=\n\n1\n2\n\n\n\n0\n\n\nπ\n4\n\n\n\n\n\n(\n\n1\n+\ncos\n\n2\nθ\n\n)\n\n\nd\n\nθ\n\n   M1

\n

\n=\n\n1\n2\n\n\n\n[\n\nθ\n+\n\n\nsin\n\n2\nθ\n\n2\n\n\n]\n\n0\n\n\nπ\n4\n\n\n\n     A1

\n

\n=\n\nπ\n8\n\n+\n\n1\n4\n\n     A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.AHL.TZ2.H_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

Consider \nw\n=\n2\n\n(\n\n\ncos\n\n\nπ\n3\n\n+\n\ni\n\n\n\nsin\n\n\nπ\n3\n\n\n)\n\n

\n
\n

These four points form the vertices of a quadrilateral, Q.

\n
\n

Express w2 and w3 in modulus-argument form.

\n
[3]
\n
a.i.
\n
\n

Sketch on an Argand diagram the points represented by w0 , w1 , w2 and w3.

\n
[2]
\n
a.ii.
\n
\n

Show that the area of the quadrilateral Q is  21 3 2 .

\n
[3]
\n
b.
\n
\n

Let z = 2 ( cos π n + i sin π n ) , n Z + . The points represented on an Argand diagram by  z 0 , z 1 , z 2 , , z n  form the vertices of a polygon  P n .

\n

Show that the area of the polygon  P n  can be expressed in the form  a ( b n 1 ) sin π n , where  a , b R .

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

w 2 = 4 cis ( 2 π 3 ) ; w 3 = 8 cis ( π )      (M1)A1A1

\n

Note: Accept Euler form.

\n

Note: M1 can be awarded for either both correct moduli or both correct arguments.

\n

Note: Allow multiplication of correct Cartesian form for M1, final answers must be in modulus-argument form.

\n

[3 marks]

\n
a.i.
\n
\n

     A1A1

\n

[2 marks]

\n
a.ii.
\n
\n

use of area =  1 2 a b sin C      M1

\n

1 2 × 1 × 2 × sin π 3 + 1 2 × 2 × 4 × sin π 3 + 1 2 × 4 × 8 × sin π 3       A1A1

\n

Note: Award A1 for  C = π 3 , A1 for correct moduli.

\n

= 21 3 2      AG

\n

Note: Other methods of splitting the area may receive full marks.

\n

[3 marks]

\n
b.
\n
\n

1 2 × 2 0 × 2 1 × sin π n + 1 2 × 2 1 × 2 2 × sin π n + 1 2 × 2 2 × 2 3 × sin π n + + 1 2 × 2 n 1 × 2 n × sin π n       M1A1

\n

Note: Award M1 for powers of 2, A1 for any correct expression including both the first and last term.

\n

= sin π n × ( 2 0 + 2 2 + 2 4 + + 2 n 2 )

\n

identifying a geometric series with common ratio 22(= 4)     (M1)A1

\n

= 1 2 2 n 1 4 × sin π n      M1

\n

Note: Award M1 for use of formula for sum of geometric series.

\n

= 1 3 ( 4 n 1 ) sin π n      A1

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.AHL.TZ1.H_11", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form" ] }, { "Question": "
\n

Using the substitution \nu\n=\n\nsin\n\n\nx\n, find \n\n\n\n\n\nco\n\n\n\n\ns\n\n3\n\n\nx\n\n\nd\n\nx\n\n\n\n\nsin\n\n\nx\n\n\n\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nu\n=\n\nsin\n\n\nx\n\n\nd\n\nu\n=\n\ncos\n\n\nx\n\nd\n\nx\n       (A1)

\n

valid attempt to write integral in terms of \nu\n and \n\nd\n\nu\n      M1

\n

\n\n\n\n\n\nco\n\n\n\n\ns\n\n3\n\n\nx\n\n\nd\n\nx\n\n\n\n\nsin\n\n\nx\n\n\n\n\n=\n\n\n\n\n\n(\n\n1\n\n\n\nu\n2\n\n\n\n)\n\n\nd\n\nu\n\n\n\nu\n\n\n\n\n      A1

\n

\n=\n\n\n\n(\n\n\n\nu\n\n\n\n1\n2\n\n\n\n\n\n\n\nu\n\n\n3\n2\n\n\n\n\n\n)\n\n\n\n\nd\n\nu\n

\n

\n=\n2\n\n\nu\n\n\n1\n2\n\n\n\n\n\n\n\n2\n\n\nu\n\n\n5\n2\n\n\n\n\n\n5\n\n\n(\n\n+\nc\n\n)\n\n       (A1)

\n

\n=\n2\n\n\nsin\n\n\nx\n\n\n\n\n2\n\n\n\n\n(\n\n\n\nsin\n\n\nx\n\n\n)\n\n\n5\n\n\n\n5\n\n\n(\n\n+\nc\n\n)\n\n or equivalent       A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ2.H_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

For a study, a researcher collected 200 leaves from oak trees. After measuring the lengths of the leaves, in cm, she produced the following cumulative frequency graph.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/06\"

\n
\n

The researcher finds that 10% of the leaves have a length greater than \nk\n cm.

\n
\n

Write down the median length of these leaves.

\n
[1]
\n
a.
\n
\n

Write down the number of leaves with a length less than or equal to 8 cm.

\n
[1]
\n
b.
\n
\n

Use the graph to find the value of \nk\n.

\n
[2]
\n
c.i.
\n
\n

Before measuring, the researcher estimated \nk\n to be approximately 9.5 cm. Find the percentage error in her estimate.

\n
[2]
\n
c.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

9 (cm)     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

40 (leaves)     (A1)     (C1)

\n

[1 mark]

\n
b.
\n
\n

\n(\n200\n×\n0.90\n=\n)\n\n \n\n180\n or equivalent     (M1)

\n

 

\n

Note:     Award (M1) for a horizontal line drawn through the cumulative frequency value of 180 and meeting the curve (or the corresponding vertical line from 10.5 cm).

\n

 

\n

\n(\nk\n=\n)\n\n \n\n10.5\n\n (cm)\n\n     (A1)     (C2)

\n

 

\n

Note:     Accept an error of ±0.1.

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

\n\n|\n\n\n\n9.5\n\n10.5\n\n\n10.5\n\n\n\n|\n\n×\n100\n%\n     (M1)

\n

 

\n

Notes:     Award (M1) for their correct substitution into the percentage error formula.

\n

 

\n

\n\n9.52 (% ) \n\n\n(\n\n\n9.52380\n\n\n\n (% )\n\n\n)\n\n     (A1)(ft)     (C2)

\n

 

\n

Notes:     Follow through from their answer to part (c)(i).

\n

Award (A1)(A0) for an answer of \n\n9.52\n with or without working.

\n

 

\n

[2 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "17M.1.SL.TZ2.T_6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

The weight, W, of basketball players in a tournament is found to be normally distributed with a mean of 65 kg and a standard deviation of 5 kg.

\n
\n

The probability that a basketball player has a weight that is within 1.5 standard deviations of the mean is q.

\n
\n

A basketball coach observed 60 of her players to determine whether their performance and their weight were independent of each other. Her observations were recorded as shown in the table.

\n

\n

She decided to conduct a χ 2 test for independence at the 5% significance level.

\n
\n

Find the probability that a basketball player has a weight that is less than 61 kg.

\n
[2]
\n
a.i.
\n
\n

In a training session there are 40 basketball players.

\n

Find the expected number of players with a weight less than 61 kg in this training session.

\n
[2]
\n
a.ii.
\n
\n

Sketch a normal curve to represent this probability.

\n
[2]
\n
b.i.
\n
\n

Find the value of q.

\n
[1]
\n
b.ii.
\n
\n

Given that P(W > k) = 0.225 , find the value of k.

\n
[2]
\n
c.
\n
\n

For this test state the null hypothesis.

\n
[1]
\n
d.i.
\n
\n

For this test find the p-value.

\n
[2]
\n
d.ii.
\n
\n

State a conclusion for this test. Justify your answer.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

P(W < 61)    (M1)

\n

Note: Award (M1) for correct probability statement.

\n

OR

\n

 (M1)

\n

Note: Award (M1) for correct region labelled and shaded on diagram.

\n

= 0.212 (0.21185…, 21.2%)     (A1)(G2)

\n

[2 marks]

\n
a.i.
\n
\n

40 × 0.21185…     (M1)

\n

Note: Award (M1) for product of 40 and their 0.212.

\n

= 8.47 (8.47421...)     (A1)(ft)(G2)

\n

Note: Follow through from their part (a)(i) provided their answer to part (a)(i) is less than 1.

\n

[2 marks]

\n
a.ii.
\n
\n

 

\n

    (A1)(M1)

\n

Note: Award (A1) for two correctly labelled vertical lines in approximately correct positions. The values 57.5 and 72.5, or μ − 1.5σ and μ + 1.5σ are acceptable labels. Award (M1) for correctly shaded region marked by their two vertical lines.

\n

[2 marks]

\n
b.i.
\n
\n

0.866 (0.86638…, 86.6%)      (A1)(ft)

\n

Note: Follow through from their part (b)(i) shaded region if their values are clear.

\n

[1 mark]

\n
b.ii.
\n
\n

P(W < k) = 0.775     (M1)

\n

OR

\n

  (M1)

\n

Note: Award (A1) for correct region labelled and shaded on diagram.

\n

(k =) 68.8  (68.7770…)     (A1)(G2)

\n

[2 marks]

\n
c.
\n
\n

(H0:) performance (of players) and (their) weight are independent.     (A1)

\n

Note: Accept “there is no association between performance (of players) and (their) weight”. Do not accept \"not related\" or \"not correlated\" or \"not influenced\".

\n

[1 mark]

\n
d.i.
\n
\n

0.287  (0.287436…)     (G2)

\n

[2 marks]

\n
d.ii.
\n
\n

accept/ do not reject null hypothesis/H0     (A1)(ft)

\n

OR

\n

performance (of players) and (their) weight are independent. (A1)(ft)

\n

0.287 > 0.05     (R1)(ft)

\n

Note: Accept p-value>significance level provided their p-value is seen in b(ii). Accept 28.7% > 5%. Do not award (A1)(R0). Follow through from part (d).

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.2.SL.TZ2.T_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Use the substitution \nu\n=\n\n\nx\n\n\n1\n2\n\n\n\n\n to find \n\n\n\n\n\nd\n\nx\n\n\n\n\nx\n\n\n3\n2\n\n\n\n\n+\n\n\nx\n\n\n1\n2\n\n\n\n\n\n\n\n.

\n
[4]
\n
a.
\n
\n

Hence find the value of \n\n1\n2\n\n\n\n1\n9\n\n\n\n\n\nd\n\nx\n\n\n\n\nx\n\n\n3\n2\n\n\n\n\n+\n\n\nx\n\n\n1\n2\n\n\n\n\n\n\n\n, expressing your answer in the form arctan \nq\n, where \nq\n\n\nQ\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n\n1\n2\n\n\n\nx\n\n\n\n1\n2\n\n\n\n\n (accept \n\nd\n\nu\n=\n\n1\n2\n\n\n\nx\n\n\n\n1\n2\n\n\n\n\n\nd\n\nx\n or equivalent)       A1

\n

substitution, leading to an integrand in terms of \nu\n     M1

\n

\n\n\n\n\n2\nu\n\nd\n\nu\n\n\n\n\nu\n3\n\n\n+\nu\n\n\n\n or equivalent      A1

\n

= 2 arctan \n\n(\n\n\nx\n\n\n)\n\n\n(\n\n+\nc\n\n)\n\n     A1

\n

[4 marks]

\n

 

\n
a.
\n
\n

 

\n

\n\n1\n2\n\n\n\n1\n9\n\n\n\n\n\nd\n\nx\n\n\n\n\nx\n\n\n3\n2\n\n\n\n\n+\n\n\nx\n\n\n1\n2\n\n\n\n\n\n\n\n = arctan 3 − arctan 1     A1

\n

tan(arctan 3 − arctan 1) = \n\n\n3\n\n1\n\n\n1\n+\n3\n×\n1\n\n\n      (M1)

\n

tan(arctan 3 − arctan 1) = \n\n1\n2\n\n

\n

arctan 3 − arctan 1 = arctan \n\n1\n2\n\n     A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.AHL.TZ2.H_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

All the children in a summer camp play at least one sport, from a choice of football (\nF\n) or basketball (\nB\n). 15 children play both sports.

\n

The number of children who play only football is double the number of children who play only basketball.

\n

Let \nx\n be the number of children who play only football.

\n
\n

There are 120 children in the summer camp.

\n
\n

Write down an expression, in terms of x , for the number of children who play only basketball.

\n
[1]
\n
a.
\n
\n

Complete the Venn diagram using the above information.

\n

\n
[2]
\n
b.
\n
\n

Find the number of children who play only football.

\n
[2]
\n
c.
\n
\n

Write down the value of n ( F ) .

\n
[1]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

1 2 x     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

   (A1)(A1)(ft)     (C2)

\n

 

\n

Notes:     Award (A1) for 15 placed in the correct position, award (A1)(ft) for x and their 1 2 x placed in the correct positions of diagram. Do not penalize the absence of 0 inside the rectangle and award at most (A1)(A0) if any value other than 0 is seen outside the circles. Award at most (A1)(A0) if 35 and 70 are seen instead of x and their 1 2 x .

\n

 

\n

[2 marks]

\n
b.
\n
\n

x + 1 2 x + 15 = 120 or equivalent     (M1)

\n

 

\n

Note:     Award (M1) for adding the values in their Venn and equating to 120 (or equivalent).

\n

 

\n

( x = )   70     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from their Venn diagram, but only if the answer is a positive integer and x is seen in their Venn diagram.

\n

 

\n

[2 marks]

\n
c.
\n
\n

85     (A1)(ft)     (C1)

\n

 

\n

Note:     Follow through from their Venn diagram and their answer to part (c), but only if the answer is a positive integer and less than 120.

\n

 

\n

[1 mark]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.1.SL.TZ2.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\nsec\n\n\nx\n+\n2\n, \n0\n\nx\n<\n\nπ\n2\n\n.

\n
\n

Use integration by parts to find \n\n\n\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n\n2\n\n\n\n\nd\n\nx\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

write as \n\n\n1\n×\n\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n\n2\n\n\n\n\nd\n\nx\n       (M1)

\n

\n=\nx\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\n\n\nx\n×\n\n\n2\n\n(\n\n\nln\n\n\nx\n\n)\n\n\nx\n\n\n\nd\n\nx\n\n(\n\n=\nx\n\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n\n2\n\n\n\n\n\n2\n\n\nln\n\n\nx\n\n\n)\n\n      M1A1

\n

\n=\nx\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\n2\nx\n\n\nln\n\n\nx\n+\n\n2\n\n\nd\n\nx\n       (M1)(A1)

\n

\n=\nx\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\n2\nx\n\n\nln\n\n\nx\n+\n2\nx\n+\nc\n      A1

\n

 

\n

METHOD 2

\n

let \nu\n=\n\nln\n\n\nx\n      M1

\n

\n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n\n1\nx\n\n

\n

\n\n\n\n\nu\n2\n\n\n\n\n\ne\n\nu\n\n\n\n\nd\n\nu\n      A1

\n

\n=\n\n\nu\n2\n\n\n\n\n\ne\n\nu\n\n\n\n\n\n2\nu\n\n\n\ne\n\nu\n\n\n\n\nd\n\nu\n      M1

\n

\n=\n\n\nu\n2\n\n\n\n\n\ne\n\nu\n\n\n\n2\nu\n\n\n\ne\n\nu\n\n\n+\n\n\n2\n\n\n\ne\n\nu\n\n\n\n\nd\n\nu\n      A1

\n

\n=\n\n\nu\n2\n\n\n\n\n\ne\n\nu\n\n\n\n2\nu\n\n\n\ne\n\nu\n\n\n+\n2\n\n\n\ne\n\nu\n\n\n+\nc\n

\n

\n=\nx\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\n2\nx\n\n\nln\n\n\nx\n+\n2\nx\n+\nc\n      M1A1

\n

 

\n

METHOD 3

\n

Setting up \nu\n=\n\nln\n\n\nx\n and \n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\nln\n\n\nx\n      M1

\n

\n\nln\n\n\nx\n\n(\n\nx\n\n\nln\n\n\nx\n\nx\n\n)\n\n\n\n\n\n(\n\n\nln\n\n\nx\n\n1\n\n)\n\n\n\nd\n\nx\n     M1A1

\n

\n=\nx\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\nx\n\n\nln\n\n\nx\n\n\n(\n\nx\n\n\nln\n\n\nx\n\nx\n\n)\n\n+\nx\n+\nc\n     M1A1

\n

\n=\nx\n\n\n\n(\n\n\nln\n\n\nx\n\n)\n\n2\n\n\n\n2\nx\n\n\nln\n\n\nx\n+\n2\nx\n+\nc\n      A1

\n

 

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.2.AHL.TZ1.H_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

Consider the complex numbers \n\n\nz\n1\n\n\n=\n1\n+\n\n3\n\n\ni, \n\n\n\nz\n2\n\n\n=\n1\n+\n\ni\n\n and \nw\n=\n\n\n\n\nz\n1\n\n\n\n\n\n\nz\n2\n\n\n\n\n.

\n
\n

By expressing \n\n\nz\n1\n\n\n and \n\n\nz\n2\n\n\n in modulus-argument form write down the modulus of \nw\n;

\n
[3]
\n
a.i.
\n
\n

By expressing \n\n\nz\n1\n\n\n and \n\n\nz\n2\n\n\n in modulus-argument form write down the argument of \nw\n.

\n
[1]
\n
a.ii.
\n
\n

Find the smallest positive integer value of \nn\n, such that \n\n\nw\nn\n\n\n is a real number.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

\n\n\nz\n1\n\n\n=\n2\n\ncis\n\n\n(\n\n\nπ\n3\n\n\n)\n\n and \n\n\nz\n2\n\n\n=\n\n2\n\n\ncis\n\n\n(\n\n\nπ\n4\n\n\n)\n\n     A1A1

\n

 

\n

Note:     Award A1A0 for correct moduli and arguments found, but not written in mod-arg form.

\n

 

\n

\n\n|\nw\n|\n\n=\n\n2\n\n     A1

\n

[3 marks]

\n
a.i.
\n
\n

\n\n\nz\n1\n\n\n=\n2\n\ncis\n\n\n(\n\n\nπ\n3\n\n\n)\n\n and \n\n\nz\n2\n\n\n=\n\n2\n\n\ncis\n\n\n(\n\n\nπ\n4\n\n\n)\n\n     A1A1

\n

 

\n

Note:     Award A1A0 for correct moduli and arguments found, but not written in mod-arg form.

\n

 

\n

\narg\n\nw\n=\n\nπ\n\n12\n\n\n     A1

\n

 

\n

Notes:     Allow FT from incorrect answers for \n\n\nz\n1\n\n\n and \n\n\nz\n2\n\n\n in modulus-argument form.

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

EITHER

\n

\nsin\n\n\n(\n\n\n\nπ\nn\n\n\n12\n\n\n\n)\n\n=\n0\n     (M1)

\n

OR

\n

\narg\n\n(\n\n\nw\nn\n\n\n)\n=\nπ\n     (M1)

\n

\n\n\nn\nπ\n\n\n12\n\n\n=\nπ\n

\n

THEN

\n

\n\nn\n=\n12\n     A1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.AHL.TZ1.H_2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form" ] }, { "Question": "
\n

Find \n\n\narcsin\n\nx\n\n\nd\n\nx\n\n

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt at integration by parts with \nu\n=\narcsin\n\nx\n and \n\nv\n\n\n=\n1\n     M1

\n

\n\n\narcsin\n\nx\n\n\nd\n\nx\n\n=\nx\narcsin\n\nx\n\n\n\n\nx\n\n\n1\n\n\n\nx\n2\n\n\n\n\n\n\nd\n\nx\n\n\n \n\n    A1A1

\n

 

\n

Note:     Award A1 for \nx\narcsin\n\nx\n and A1 for \n\n\n\n\nx\n\n\n1\n\n\n\nx\n2\n\n\n\n\n\n\nd\n\nx\n\n.

\n

 

\n

solving \n\n\n\nx\n\n\n1\n\n\n\nx\n2\n\n\n\n\n\n\nd\n\nx\n\n by substitution with \nu\n=\n1\n\n\n\nx\n2\n\n\n or inspection     (M1)

\n

\n\n\narcsin\n\nx\n\nd\n\nx\n\n=\nx\narcsin\n\nx\n+\n\n1\n\n\n\nx\n2\n\n\n\n+\nc\n   A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.AHL.TZ1.H_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

Let \np\n=\n\n\ncos\n\nx\n+\nsin\n\ny\n\n\n\n\n\nw\n2\n\n\n\nz\n\n\n\n,

\n

where \nx\n=\n\n36\n\n\n,\n\n \n\ny\n=\n\n18\n\n\n,\n\n \n\nw\n=\n29\n and \nz\n=\n21.8\n.

\n
\n

Calculate the value of \np\n. Write down your full calculator display.

\n
[2]
\n
a.
\n
\n

Write your answer to part (a)

\n

(i)     correct to two decimal places;

\n

(ii)     correct to three significant figures.

\n
[2]
\n
b.
\n
\n

Write your answer to part (b)(ii) in the form \na\n×\n\n\n10\nk\n\n\n, where \n1\n\na\n<\n10\n,\n\n \n\nk\n\n\nZ\n\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\ncos\n\n\n36\n\n\n+\nsin\n\n\n18\n\n\n\n\n\n\n\n\n29\n\n2\n\n\n\n21.8\n\n\n\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into formula.

\n

 

\n

\n=\n0.0390625\n    (A1)     (C2)

\n

 

\n

Note:     Accept \n\n5\n\n128\n\n\n.

\n

 

\n

[2 marks]

\n
a.
\n
\n

(i)     0.04     (A1)(ft)

\n

(ii)     0.0391     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n3.91\n×\n\n\n10\n\n\n2\n\n\n\n    (A1)(ft)(A1)(ft)     (C2)

\n

 

\n

Note:     Answer should be consistent with their answer to part (b)(ii). Award (A1)(ft) for 3.91, and (A1)(ft) for \n\n\n10\n\n\n2\n\n\n\n. Follow through from part (b)(ii).

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.1.SL.TZ0.T_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-1-using-standard-form" ] }, { "Question": "
\n

The random variables X , Y follow a bivariate normal distribution with product moment correlation coefficient ρ.

\n
\n

A random sample of 11 observations on X, Y was obtained and the value of the sample product moment correlation coefficient, r, was calculated to be −0.708.

\n
\n

The covariance of the random variables U, V is defined by

\n

Cov(U, V) = E((U − E(U))(V − E(V))).

\n
\n

State suitable hypotheses to investigate whether or not a negative linear association exists between X and Y.

\n
[1]
\n
a.
\n
\n

Determine the p-value.

\n
[3]
\n
b.i.
\n
\n

State your conclusion at the 1 % significance level.

\n
[1]
\n
b.ii.
\n
\n

Show that Cov(U, V) = E(UV) − E(U)E(V).

\n
[3]
\n
c.i.
\n
\n

Hence show that if U, V are independent random variables then the population product moment correlation coefficient, ρ, is zero.

\n
[3]
\n
c.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

H0 : ρ = 0; H1 ρ < 0       A1

\n

[1 mark]

\n
a.
\n
\n

\nt\n=\n\n0.708\n\n\n\n11\n\n2\n\n\n1\n\n\n\n\n\n(\n\n\n0.708\n\n)\n\n\n2\n\n\n\n\n\n\n\n=\n\n\n\n(\n\n\n3.0075\n\n\n)\n\n       (M1)

\n

degrees of freedom = 9        (A1)

\n

P(T < −3.0075...) = 0.00739       A1

\n

Note: Accept any answer that rounds to 0.0074.

\n

[3 marks]

\n
b.i.
\n
\n

reject H0 or equivalent statement       R1

\n

Note: Apply follow through on the candidate’s p-value.

\n

[1 mark]

\n
b.ii.
\n
\n

Cov(U, V) + E((U − E(U))(V − E(V)))

\n

= E(UV − E(U)V − E(V)+ E(U)E(V))       M1

\n

= E(UV) − E(E(U)V) − E(E(V)U) + E(E(U)E(V))       (A1)

\n

= E(UV) − E(U)E(V) − E(V)E(U) + E(U)E(V)       A1

\n

Cov(U, V) = E(UV) − E(U)E(V)       AG

\n

[3 marks]

\n
c.i.
\n
\n

E(UV) = E(U)E(V) (independent random variables)       R1

\n

⇒Cov(U, V) = E(U)E(V) − E(U)E(V) = 0      A1

\n

hence, ρ = \n\n\n\nCov\n\n\n(\n\nU\n,\n\nV\n\n)\n\n\n\n\n\nVar\n\n\n(\nU\n)\n\n\n\nVar\n\n\n(\nV\n)\n\n\n\n\n=\n0\n     A1AG

\n

Note: Accept the statement that Cov(U,V) is the numerator of the formula for ρ.

\n

Note: Only award the first A1 if the R1 is awarded.

\n

[3 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "18M.3.AHL.TZ0.HSP_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A manufacturer makes trash cans in the form of a cylinder with a hemispherical top. The trash can has a height of 70 cm. The base radius of both the cylinder and the hemispherical top is 20 cm.

\n

\n
\n

A designer is asked to produce a new trash can.

\n

The new trash can will also be in the form of a cylinder with a hemispherical top.

\n

This trash can will have a height of H cm and a base radius of r cm.

\n

\n

There is a design constraint such that H + 2r = 110 cm.

\n

The designer has to maximize the volume of the trash can.

\n
\n

Write down the height of the cylinder.

\n
[1]
\n
a.
\n
\n

Find the total volume of the trash can.

\n
[4]
\n
b.
\n
\n

Find the height of the cylinder, h , of the new trash can, in terms of r.

\n
[2]
\n
c.
\n
\n

Show that the volume, V cm3 , of the new trash can is given by

\n

V = 110 π r 3 .

\n
[3]
\n
d.
\n
\n

Using your graphic display calculator, find the value of r which maximizes the value of V.

\n
[2]
\n
e.
\n
\n

The designer claims that the new trash can has a capacity that is at least 40% greater than the capacity of the original trash can.

\n

State whether the designer’s claim is correct. Justify your answer.

\n
[4]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

50 (cm)      (A1)

\n

[1 mark]

\n
a.
\n
\n

π × 50 × 20 2 + 1 2 × 4 3 × π × 20 3      (M1)(M1)(M1)

\n

Note: Award (M1) for their correctly substituted volume of cylinder, (M1) for correctly substituted volume of sphere formula, (M1) for halving the substituted volume of sphere formula. Award at most (M1)(M1)(M0) if there is no addition of the volumes.

\n

= 79600 ( c m 3 ) ( 79587.0 ( c m 3 ) , 76000 3 π )      (A1)(ft) (G3)

\n

Note: Follow through from part (a).

\n

[4 marks]

\n
b.
\n
\n

h = H − r (or equivalent) OR H = 110 − 2r     (M1)

\n

Note: Award (M1) for writing h in terms of H and r or for writing H in terms of r.

\n

(h =) 110 3r     (A1) (G2)

\n

[2 marks]

\n
c.
\n
\n

( V = ) 2 3 π r 3 + π r 2 × ( 110 3 r )     (M1)(M1)(M1)

\n

Note: Award (M1) for volume of hemisphere, (M1) for correct substitution of their h into the volume of a cylinder, (M1) for addition of two correctly substituted volumes leading to the given answer. Award at most (M1)(M1)(M0) for subsequent working that does not lead to the given answer. Award at most (M1)(M1)(M0) for substituting H = 110 − 2r as their h.

\n

V = 110 π r 2 7 3 π r 3     (AG)

\n

[3 marks]

\n
d.
\n
\n

(r =) 31.4 (cm)  (31.4285… (cm))     (G2)

\n

OR

\n

( π ) ( 220 r 7 r 2 ) = 0       (M1)

\n

Note: Award (M1) for setting the correct derivative equal to zero.

\n

(r =) 31.4 (cm)  (31.4285… (cm))     (A1)

\n

[2 marks]

\n
e.
\n
\n

( V = ) 110 π ( 31.4285 ) 3 7 3 π ( 31.4285 ) 3      (M1)

\n

Note: Award (M1) for correct substitution of their 31.4285… into the given equation.

\n

= 114000 (113781…)     (A1)(ft)

\n

Note: Follow through from part (e).

\n

(increase in capacity =)  113.781 79587.0 79587.0 × 100 = 43.0 ( )      (R1)(ft)

\n

Note: Award (R1)(ft) for finding the correct percentage increase from their two volumes.

\n

OR

\n

1.4 × 79587.0… = 111421.81…     (R1)(ft)

\n

Note: Award (R1)(ft) for finding the capacity of a trash can 40% larger than the original.

\n

Claim is correct (A1)(ft)

\n

Note: Follow through from parts (b), (e) and within part (f). The final (R1)(A1)(ft) can be awarded for their correct reason and conclusion. Do not award (R0)(A1)(ft).

\n

[4 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "18M.2.SL.TZ1.T_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Passengers of Flyaway Airlines can purchase tickets for either Business Class or Economy Class.

\n

On one particular flight there were 154 passengers.

\n

Let \nx\n be the number of Business Class passengers and \ny\n be the number of Economy Class passengers on this flight.

\n
\n

On this flight, the cost of a ticket for each Business Class passenger was 320 euros and the cost of a ticket for each Economy Class passenger was 85 euros. The total amount that Flyaway Airlines received for these tickets was \n\n14\n\n\n\n970 euros\n\n.

\n
\n

The airline’s finance officer wrote down the total amount received by the airline for these tickets as \n\n14\n\n\n\n270 euros\n\n.

\n
\n

Use the above information to write down an equation in \nx\n and \ny\n.

\n
[1]
\n
a.
\n
\n

Use the information about the cost of tickets to write down a second equation in \nx\n and \ny\n.

\n
[1]
\n
b.
\n
\n

Find the value of \nx\n and the value of \ny\n.

\n
[2]
\n
c.
\n
\n

Find the percentage error.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nx\n+\ny\n=\n154\n    (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

\n320\nx\n+\n85\ny\n=\n14\n\n970\n    (A1)     (C1)

\n

[1 mark]

\n
b.
\n
\n

\nx\n=\n8\n,\n\n \n\ny\n=\n146\n    (A1)(ft)(A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from parts (a) and (b) irrespective of working seen, but only if both values are positive integers.

\n

Award (M1)(A0) for a reasonable attempt to solve simultaneous equations algebraically, leading to at least one incorrect or missing value.

\n

 

\n

[2 marks]

\n
c.
\n
\n

\n\n|\n\n\n\n14270\n\n14970\n\n\n14970\n\n\n\n|\n\n×\n\n \n\n100\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into percentage error formula.

\n

 

\n

\n=\n4.68\n(\n%\n)\n\n \n\n(\n4.67601\n\n)\n\n \n\n    (A1) (C2)

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "16N.1.SL.TZ0.T_8", "topics": [], "subtopics": [] }, { "Question": "
\n

Consider the complex number \nz\n=\n\n\n2\n+\n7\n\ni\n\n\n\n6\n+\n2\n\ni\n\n\n\n.

\n
\n

Express \nz\n in the form \na\n+\n\ni\n\nb\n, where \na\n,\n\nb\n\n\nQ\n\n.

\n
[2]
\n
a.
\n
\n

Find the exact value of the modulus of \nz\n.

\n
[2]
\n
b.
\n
\n

Find the argument of \nz\n, giving your answer to 4 decimal places.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nz\n=\n\n\n\n(\n\n2\n+\n7\n\ni\n\n\n)\n\n\n\n\n(\n\n6\n+\n2\n\ni\n\n\n)\n\n\n\n×\n\n\n\n(\n\n6\n\n2\n\ni\n\n\n)\n\n\n\n\n(\n\n6\n\n2\n\ni\n\n\n)\n\n\n\n     (M1)

\n

\n=\n\n\n26\n+\n38\n\ni\n\n\n\n40\n\n\n=\n\n(\n\n\n\n13\n+\n19\n\ni\n\n\n\n20\n\n\n=\n0.65\n+\n0.95\n\ni\n\n\n)\n\n     A1

\n

[2 marks]

\n
a.
\n
\n

attempt to use \n\n|\nz\n|\n\n=\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n    (M1)

\n

\n\n|\nz\n|\n\n=\n\n\n\n53\n\n\n40\n\n\n\n\n(\n\n=\n\n\n\n530\n\n\n\n20\n\n\n\n)\n\n or equivalent      A1

\n

Note: A1 is only awarded for the correct exact value.

\n

[2 marks]

\n
b.
\n
\n

EITHER

\n

arg \nz\n = arg(2 + 7i) − arg(6 + 2i)      (M1)

\n

OR

\n

arg \nz\n = arctan\n\n(\n\n\n\n19\n\n\n13\n\n\n\n)\n\n         (M1)

\n

THEN

\n

arg \nz\n = 0.9707 (radians) (= 55.6197 degrees)     A1

\n

Note: Only award the last A1 if 4 decimal places are given.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.AHL.TZ2.H_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form" ] }, { "Question": "
\n

Find the roots of the equation \n\n\nw\n3\n\n\n=\n8\n\ni\n\n, \nw\n\n\nC\n\n. Give your answers in Cartesian form.

\n
[4]
\n
a.
\n
\n

One of the roots \n\n\nw\n1\n\n\n satisfies the condition \n\nRe\n\n\n(\n\n\n\nw\n1\n\n\n\n)\n\n=\n0\n.

\n

Given that \n\n\nw\n1\n\n\n=\n\nz\n\nz\n\n\ni\n\n\n\n, express \nz\n in the form \na\n+\nb\n\ni\n\n, where \na\n, \nb\n\n\nQ\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\n\nw\n3\n\n\n=\n8\n\ni\n\n

\n

writing \n8\n\ni\n\n=\n8\n\n(\n\n\ncos\n\n\n(\n\n\nπ\n2\n\n+\n2\nπ\nk\n\n)\n\n+\n\ni\n\n\n\nsin\n\n\n(\n\n\nπ\n2\n\n+\n2\nπ\nk\n\n)\n\n\n)\n\n              (M1)

\n

Note: Award M1 for an attempt to find cube roots of \nw\n using modulus-argument form.

\n

cube roots  \nw\n=\n2\n\n(\n\n\ncos\n\n\n(\n\n\n\n\nπ\n2\n\n+\n2\nπ\nk\n\n3\n\n\n)\n\n+\n\ni\n\n\n\nsin\n\n\n(\n\n\n\n\nπ\n2\n\n+\n2\nπ\nk\n\n3\n\n\n)\n\n\n)\n\n              (M1)

\n

i.e. \nw\n=\n\n3\n\n+\n\ni,\n\n\n\n\n\n3\n\n+\n\ni,\n\n\n\n\n2\n\ni\n\n         A2

\n

Note: Award A2 for all 3 correct, A1 for 2 correct.

\n

Note: Accept \nw\n=\n1.73\n+\n\ni\n\n and \nw\n=\n\n1.73\n+\n\ni\n\n.

\n

 

\n

METHOD 2

\n

\n\n\nw\n3\n\n\n+\n\n\n\n(\n\n2\n\ni\n\n\n)\n\n3\n\n\n=\n0\n

\n

\n\n(\n\nw\n+\n2\n\ni\n\n\n)\n\n\n(\n\n\n\nw\n2\n\n\n\n2\nw\n\ni\n\n\n4\n\n)\n\n=\n0\n              M1

\n

\nw\n=\n\n\n2\n\ni\n\n±\n\n12\n\n\n2\n\n              M1

\n

\nw\n=\n\n3\n\n+\n\ni,\n\n\n\n\n\n3\n\n+\n\ni,\n\n\n\n\n2\n\ni\n\n         A2

\n

Note: Award A2 for all 3 correct, A1 for 2 correct.

\n

Note: Accept \nw\n=\n1.73\n+\n\ni\n\n and \nw\n=\n\n1.73\n+\n\ni\n\n.

\n

 

\n

[4 marks]

\n
a.
\n
\n

\n\n\nw\n1\n\n\n=\n\n2\n\ni\n\n

\n

\n\nz\n\nz\n\n\ni\n\n\n\n=\n\n2\n\ni\n\n      M1

\n

\nz\n=\n\n2\n\ni\n\n\n(\n\nz\n\n\ni\n\n\n)\n\n

\n

\nz\n\n(\n\n1\n+\n2\n\ni\n\n\n)\n\n=\n\n2\n

\n

\nz\n=\n\n\n\n2\n\n\n1\n+\n2\n\ni\n\n\n\n      A1

\n

\nz\n=\n\n\n2\n5\n\n+\n\n4\n5\n\n\ni\n\n      A1

\n

Note: Accept \na\n=\n\n\n2\n5\n\n\n,\n\n\n\nb\n=\n\n4\n5\n\n.

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.AHL.TZ2.H_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form" ] }, { "Question": "
\n

Consider the functions \nf\n\ng\n\n\nR\n\n×\n\nR\n\n\n\nR\n\n×\n\nR\n\n defined by

\n

\nf\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n=\n\n(\n\nx\n+\ny\n,\n\n\nx\n\ny\n\n)\n\n and \ng\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n=\n\n(\n\nx\ny\n,\n\n\nx\n+\ny\n\n)\n\n.

\n
\n

Find \n\n(\n\nf\n\ng\n\n)\n\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n.

\n
[3]
\n
a.i.
\n
\n

Find \n\n(\n\ng\n\nf\n\n)\n\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n.

\n
[2]
\n
a.ii.
\n
\n

State with a reason whether or not \nf\n and \ng\n commute.

\n
[1]
\n
b.
\n
\n

Find the inverse of \nf\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

\n\n(\n\nf\n\ng\n\n)\n\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n=\nf\n\n(\n\ng\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n\n)\n\n  (\n=\nf\n\n(\n\n\n(\n\nx\ny\n,\n\n\nx\n+\ny\n\n)\n\n\n)\n\n)       (M1)

\n

\n=\n\n(\n\nx\ny\n+\nx\n+\ny\n,\n\n\nx\ny\n\nx\n\ny\n\n)\n\n       A1A1

\n

 

\n

[3 marks]

\n
a.i.
\n
\n

\n\n(\n\ng\n\nf\n\n)\n\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n=\ng\n\n(\n\nf\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n\n)\n\n

\n

\n=\ng\n\n(\n\n\n(\n\nx\n+\ny\n,\n\n\nx\n\ny\n\n)\n\n\n)\n\n

\n

\n=\n\n(\n\n\n(\n\nx\n+\ny\n\n)\n\n\n(\n\nx\n\ny\n\n)\n\n,\n\n\nx\n+\ny\n+\nx\n\ny\n\n)\n\n

\n

\n=\n\n(\n\n\n\nx\n2\n\n\n\n\n\ny\n2\n\n\n\n,\n\n\n\n2\nx\n\n)\n\n       A1A1

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

no because \nf\n\ng\n\ng\n\nf\n        R1

\n

Note: Accept counter example.

\n

 

\n

[1 mark]

\n
b.
\n
\n

 

\n

\nf\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n=\n\n(\n\na\n\n,\n\n\n\nb\n\n)\n\n\n\n(\n\nx\n+\ny\n,\n\n\nx\n\ny\n\n)\n\n=\n\n(\n\na\n\n,\n\n\n\nb\n\n)\n\n       (M1)

\n

\n\n{\n\n\n\n\n\nx\n=\n\n\na\n+\nb\n\n2\n\n\n\n\n\n\n\ny\n=\n\n\na\n\nb\n\n2\n\n\n\n\n\n\n\n\n       (M1)

\n

\n\n\nf\n\n\n1\n\n\n\n\n(\n\n\n(\n\nx\n\n,\n\n\n\ny\n\n)\n\n\n)\n\n=\n\n(\n\n\n\nx\n+\ny\n\n2\n\n,\n\n\n\n\nx\n\ny\n\n2\n\n\n)\n\n        A1

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.3.AHL.TZ0.HSRG_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

Last year a South American candy factory sold 4.8 × 108 spherical sweets. Each sweet has a diameter of 2.5 cm.

\n

The factory is producing an advertisement showing all of these sweets placed in a straight line.

\n

\n
\n

The advertisement claims that the length of this line is x times the length of the Amazon River. The length of the Amazon River is 6400 km.

\n
\n

Find the length, in cm, of this line. Give your answer in the form a × 10k , where 1 ≤ a < 10 and k ∈ \n\nZ\n\n.

\n
[3]
\n
a.
\n
\n

Write down the length of the Amazon River in cm.

\n
[1]
\n
b.i.
\n
\n

Find the value of x.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

4.8 × 108 × 2.5     (M1)

\n

Note: Award (M1) for multiplying by 2.5.

\n

1.2 × 109 (cm)     (A1)(ft)(A1)(ft) (C3)

\n

Note: Award (A0)(A0) for answers of the type 12 × 108.

\n

[3 marks]

\n
a.
\n
\n

640 000 000 (cm)  (6.4 × 108 (cm))     (A1)

\n

[1 mark]

\n
b.i.
\n
\n

\n\n\n1.2\n×\n\n\n\n10\n\n9\n\n\n\n\n6.4\n×\n\n\n\n10\n\n8\n\n\n\n\n     (M1)

\n

Note: Award (M1) for division by 640 000 000.

\n

= 1.88 (1.875)     (A1)(ft) (C3)

\n

Note: Follow through from part (a) and part (b)(i).

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18M.1.SL.TZ2.T_3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-1-using-standard-form" ] }, { "Question": "
\n

A sector of a circle with radius \nr\n cm , where \nr\n > 0, is shown on the following diagram.
The sector has an angle of 1 radian at the centre.

\n

\n

Let the area of the sector be \nA\n cm2 and the perimeter be \nP\n cm. Given that \nA\n=\nP\n, find the value of \nr\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nA\n=\nP\n

\n

use of the correct formula for area and arc length       (M1)

\n

perimeter is \nr\nθ\n+\n2\nr\n       (A1)

\n

Note: A1 independent of previous M1.

\n

\n\n1\n2\n\n\n\nr\n2\n\n\n\n(\n1\n)\n\n=\nr\n\n(\n1\n)\n\n+\n2\nr\n      A1

\n

\n\n\nr\n2\n\n\n\n6\nr\n=\n0\n

\n

\nr\n=\n6\n  (as \nr\n > 0)        A1

\n

Note: Do not award final A1 if \nr\n=\n0\n is included.

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ1.H_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

Let \nz\n=\na\n+\nb\n\ni\n\n, \na\n\n\nb\n\n\n\n\n\nR\n\n+\n\n\n and let \n\narg\n\n\nz\n=\nθ\n.

\n
\n

Show the points represented by \nz\n and \nz\n\n2\na\n on the following Argand diagram.

\n

\n
[1]
\n
a.
\n
\n

Find an expression in terms of θ for \n\narg\n\n\n(\n\nz\n\n2\na\n\n)\n\n.

\n
[1]
\n
b.i.
\n
\n

Find an expression in terms of θ for \n\narg\n\n\n(\n\n\nz\n\nz\n\n2\na\n\n\n\n)\n\n.

\n
[2]
\n
b.ii.
\n
\n

Hence or otherwise find the value of θ for which \n\nRe\n\n\n(\n\n\nz\n\nz\n\n2\na\n\n\n\n)\n\n=\n0\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

      A1

\n

Note: Award A1 for \nz\n in first quadrant and \nz\n\n2\na\n its reflection in the \ny\n-axis.

\n

[1 mark]

\n
a.
\n
\n

\nπ\n\nθ\n (or any equivalent)     A1

\n

[1 mark]

\n
b.i.
\n
\n

\n\narg\n\n\n(\n\n\nz\n\nz\n\n2\na\n\n\n\n)\n\n=\n\narg\n\n\n(\nz\n)\n\n\n\narg\n\n\n(\n\nz\n\n2\na\n\n)\n\n     (M1)

\n

\n=\n2\nθ\n\nπ\n (or any equivalent)       A1

\n

[2 marks]

\n
b.ii.
\n
\n

METHOD 1

\n

if \n\nRe\n\n\n(\n\n\nz\n\nz\n\n2\na\n\n\n\n)\n\n=\n0\n then \n2\nθ\n\nπ\n=\n\n\nn\nπ\n\n2\n\n, (\nn\n odd)     (M1)

\n

\n\nπ\n<\n2\nθ\n\nπ\n<\n0\n\nn\n=\n\n1\n

\n

\n2\nθ\n\nπ\n=\n\n\nπ\n2\n\n     (A1)

\n

\nθ\n=\n\nπ\n4\n\n       A1

\n

 

\n

METHOD 2

\n

\n\n\na\n+\nb\n\ni\n\n\n\n\na\n+\nb\n\ni\n\n\n\n=\n\n\n\n\nb\n2\n\n\n\n\n\na\n2\n\n\n\n2\na\nb\n\ni\n\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n\n      M1

\n

\n\nRe\n\n\n(\n\n\nz\n\nz\n\n2\na\n\n\n\n)\n\n=\n0\n\n\n\nb\n2\n\n\n\n\n\na\n2\n\n\n=\n0\n

\n

\nb\n=\na\n       A1

\n

\nθ\n=\n\nπ\n4\n\n       A1

\n

Note: Accept any equivalent, eg \nθ\n=\n\n\n\n7\nπ\n\n4\n\n.

\n

 

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.AHL.TZ1.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form" ] }, { "Question": "
\n

Consider the following graphs of normal distributions.

\n

\n
\n

At an airport, the weights of suitcases (in kg) were measured. The weights are normally distributed with a mean of 20 kg and standard deviation of 3.5 kg.

\n
\n

In the following table, write down the letter of the corresponding graph next to the given mean and standard deviation.

\n

\n
[2]
\n
a.
\n
\n

Find the probability that a suitcase weighs less than 15 kg.

\n
[2]
\n
b.
\n
\n

Any suitcase that weighs more than \nk\n kg is identified as excess baggage.
19.6 % of the suitcases at this airport are identified as excess baggage.

\n

Find the value of \nk\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

 (A1)(A1)  (C2)

\n

Note: Award (A1) for each correct entry.

\n

[2 marks]

\n
a.
\n
\n

  (M1)

\n

Note: Award (M1) for sketch with 15 labelled and left tail shaded OR for a correct probability statement, P(X < 15).

\n

0.0766  (0.0765637…, 7.66%)      (A1)   (C2)

\n

[2 marks]

\n
b.
\n
\n

 (M1)

\n

Note: Award (M1) for a sketch showing correctly shaded region to the right of the mean with 19.6% labelled (accept shading of the complement with 80.4% labelled) OR for a correct probability statement, P(X > \nk\n) = 0.196 or P(X\nk\n) = 0.804.

\n

23.0 (kg)  (22.9959… (kg))      (A1)   (C2)

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ1.T_11", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

A water trough which is 10 metres long has a uniform cross-section in the shape of a semicircle with radius 0.5 metres. It is partly filled with water as shown in the following diagram of the cross-section. The centre of the circle is O and the angle KOL is \nθ\n radians.

\n

\"M17/5/MATHL/HP2/ENG/TZ1/08\"

\n
\n

The volume of water is increasing at a constant rate of \n0.0008\n\n \n\n\n\n\nm\n\n3\n\n\n\n\n\ns\n\n\n\n1\n\n\n\n.

\n
\n

Find an expression for the volume of water \nV\n\n \n\n(\n\n\n\nm\n\n3\n\n\n)\n in the trough in terms of \nθ\n.

\n
[3]
\n
a.
\n
\n

Calculate \n\n\n\nd\n\nθ\n\n\n\nd\n\nt\n\n\n when \nθ\n=\n\nπ\n3\n\n.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

area of segment \n=\n\n1\n2\n\n×\n\n\n0.5\n2\n\n\n×\n(\nθ\n\nsin\n\nθ\n)\n     M1A1

\n

\nV\n=\n\narea of segment\n\n×\n10\n

\n

\nV\n=\n\n5\n4\n\n(\nθ\n\nsin\n\nθ\n)\n     A1

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

\n\n\n\nd\n\nV\n\n\n\nd\n\nt\n\n\n=\n\n5\n4\n\n(\n1\n\ncos\n\nθ\n)\n\n\n\nd\n\nθ\n\n\n\nd\n\nt\n\n\n     M1A1

\n

\n0.0008\n=\n\n5\n4\n\n\n(\n\n1\n\ncos\n\n\nπ\n3\n\n\n)\n\n\n\n\nd\n\nθ\n\n\n\nd\n\nt\n\n\n     (M1)

\n

\n\n\n\nd\n\nθ\n\n\n\nd\n\nt\n\n\n=\n0.00128\n\n \n\n(\n\nrad\n\n\n\n\ns\n\n\n1\n\n\n\n)\n     A1

\n

METHOD 2

\n

\n\n\n\nd\n\nθ\n\n\n\nd\n\nt\n\n\n=\n\n\n\nd\n\nθ\n\n\n\nd\n\nV\n\n\n×\n\n\n\nd\n\nV\n\n\n\nd\n\nt\n\n\n     (M1)

\n

\n\n\n\nd\n\nV\n\n\n\nd\n\nθ\n\n\n=\n\n5\n4\n\n(\n1\n\ncos\n\nθ\n)\n     A1

\n

\n\n\n\nd\n\nθ\n\n\n\nd\n\nt\n\n\n=\n\n\n4\n×\n0.0008\n\n\n5\n\n(\n\n1\n\ncos\n\n\nπ\n3\n\n\n)\n\n\n\n     (M1)

\n

\n\n\n\nd\n\nθ\n\n\n\nd\n\nt\n\n\n=\n0.00128\n\n(\n\n\n4\n\n3125\n\n\n\n)\n\n(\n\nrad \n\n\n\ns\n\n\n1\n\n\n\n)\n     A1

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.AHL.TZ1.H_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n\nx\n3\n\n\n\n5\n\n\nx\n2\n\n\n+\n6\nx\n\n3\n+\n\n1\nx\n\n\nx\n>\n0\n

\n
\n

The function \nf\n\n(\nx\n)\n\n=\n\n\nx\n3\n\n\n\n5\n\n\nx\n2\n\n\n+\n6\nx\n\n3\n+\n\n1\nx\n\n\nx\n>\n0\n, models the path of a river, as shown on the following map, where both axes represent distance and are measured in kilometres. On the same map, the location of a highway is defined by the function \ng\n\n(\nx\n)\n\n=\n0.5\n\n\n\n(\n3\n)\n\n\n\nx\n\n\n\n+\n1\n.

\n

\n

The origin, O(0, 0) , is the location of the centre of a town called Orangeton.

\n

A straight footpath, \nP\n, is built to connect the centre of Orangeton to the river at the point where \nx\n=\n\n1\n2\n\n.

\n
\n

Bridges are located where the highway crosses the river.

\n
\n

A straight road is built from the centre of Orangeton, due north, to connect the town to the highway.

\n
\n

Find the value of \nf\n\n(\nx\n)\n\n when \nx\n=\n\n1\n2\n\n.

\n
[2]
\n
a.
\n
\n

Find the function, \nP\n\n(\nx\n)\n\n , that would define this footpath on the map.

\n
[3]
\n
b.i.
\n
\n

State the domain of \nP\n.

\n
[2]
\n
b.ii.
\n
\n

Find the coordinates of the bridges relative to the centre of Orangeton.

\n
[4]
\n
c.
\n
\n

Find the distance from the centre of Orangeton to the point at which the road meets the highway.

\n
[2]
\n
d.
\n
\n

This straight road crosses the highway and then carries on due north.

\n

State whether the straight road will ever cross the river. Justify your answer.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nf\n\n(\n\n\n1\n2\n\n\n)\n\n=\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n3\n\n\n\n5\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n2\n\n\n+\n6\n\n(\n\n\n1\n2\n\n\n)\n\n\n3\n\n1\n\n\n(\n\n\n1\n2\n\n\n)\n\n\n\n     (M1)

\n

Note: Award (M1) for correct substitution into given function.

\n

\n\n7\n8\n\n\n\n\n(\n\n0.875\n\n)\n\n      (A1)(G2)

\n

[2 marks]

\n
a.
\n
\n

\n\n\n0\n\n\n7\n8\n\n\n\n0\n\n\n1\n2\n\n\n\n    (M1)

\n

Note: Award (M1) for correct substitution into gradient formula. Accept equivalent forms such as \n\n7\n8\n\n=\n\n1\n2\n\nm\n.

\n

\n\n7\n4\n\n  (1.75)      (A1)(ft)

\n

\nP\n\n(\nx\n)\n\n=\n\n7\n4\n\nx\n\n\n\n(\n\n1.75\nx\n\n)\n\n      (A1)(ft)(G3)

\n

Note: Follow through from part (a).

\n

[3 marks]

\n
b.i.
\n
\n

0 < \nx\n\n\n1\n2\n\n   (A1)(A1)

\n

Note: Award (A1) for both endpoints correct, (A1) for correct mathematical notation indicating an interval with two endpoints. Accept weak inequalities. Award at most (A1)(A0) for incorrect notation such as 0 − 0.5 or a written description of the domain with correct endpoints. Award at most (A1)(A0) for 0 < \ny\n\n\n1\n2\n\n.

\n

[2 marks]

\n
b.ii.
\n
\n

(0.360, 1.34)   ((0.359947…, 1.33669))   (A1)(A1)

\n

(3.63, 1.01)   ((3.63066…, 1.00926…))   (A1)(A1)

\n

Note: Award (A1)(A1) for each correct coordinate pair. Accept correct answers in the form of  x = 0.360 y = 1.34  etc. Award at most (A0)(A1)(A1)(A1)ft if one or both parentheses are omitted.

\n

[4 marks]

\n
c.
\n
\n

\ng\n\n(\n0\n)\n\n=\n0.5\n\n\n\n(\n3\n)\n\n0\n\n\n+\n1\n    (M1)

\n

1.5 (km)   (A1)(G2)

\n

[2 marks]

\n
d.
\n
\n

domain given as \nx\n>\n0\n (but equation of road is \nx\n=\n0\n)      (R1)

\n

OR

\n

(equation of road is \nx\n=\n0\n) the function of the river is asymptotic to \nx\n=\n0\n       (R1)

\n

so it does not meet the river       (A1)

\n

Note: Award the (R1) for a correct mathematical statement about the equation of the river (and the equation of the road). Justification must be based on mathematical reasoning. Do not award (R0)(A1).

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "19M.2.SL.TZ1.T_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

In the Canadian city of Ottawa:

\n

\n\n\n\n\n\n97%  of the population speak English,\n\n\n\n\n\n\n\n\n38%  of the population speak French,\n\n\n\n\n\n\n\n\n36%  of the population speak both English and French.\n\n\n\n\n\n

\n
\n

The total population of Ottawa is \n985\n\n000\n.

\n
\n

Calculate the percentage of the population of Ottawa that speak English but not French.

\n
[2]
\n
a.
\n
\n

Calculate the number of people in Ottawa that speak both English and French.

\n
[2]
\n
b.
\n
\n

Write down your answer to part (b) in the form \na\n×\n\n\n10\nk\n\n\n where \n1\n\na\n<\n10\n and k \n\n\nZ\n\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n97\n\n36\n     (M1)

\n

 

\n

Note:     Award (M1) for subtracting 36 from 97.

\n

 

\n

OR

\n

\"M17/5/MATSD/SP1/ENG/TZ1/02.a/M\"

\n

(M1)

\n

 

\n

Note:     Award (M1) for 61 and 36 seen in the correct places in the Venn diagram.

\n

 

\n

\n=\n61\n\n \n\n(\n%\n)\n     (A1)     (C2)

\n

 

\n

Note:     Accept 61.0 (%).

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n\n\n36\n\n\n100\n\n\n×\n985\n\n000\n     (M1)

\n

 

\n

Note:     Award (M1) for multiplying 0.36 (or equivalent) by \n985\n\n000\n.

\n

 

\n

\n=\n355\n\n000\n\n \n\n(\n354\n\n600\n)\n     (A1)     (C2)

\n

[2 marks]

\n
b.
\n
\n

\n3.55\n×\n\n\n10\n5\n\n\n\n \n\n(\n3.546\n×\n\n\n10\n5\n\n\n)\n     (A1)(ft)(A1)(ft)     (C2)

\n

 

\n

Note:     Award (A1)(ft) for 3.55 (3.546) must match part (b), and (A1)(ft) \n×\n\n\n10\n5\n\n\n.

\n

Award (A0)(A0) for answers of the type: \n35.5\n×\n\n\n10\n4\n\n\n. Follow through from part (b).

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ1.T_2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-1-using-standard-form" ] }, { "Question": "
\n

Sergei is training to be a weightlifter. Each day he trains at the local gym by lifting a metal bar that has heavy weights attached. He carries out successive lifts. After each lift, the same amount of weight is added to the bar to increase the weight to be lifted.

\n

The weights of each of Sergei’s lifts form an arithmetic sequence.

\n

Sergei’s friend, Yuri, records the weight of each lift. Unfortunately, last Monday, Yuri misplaced all but two of the recordings of Sergei’s lifts.

\n

On that day, Sergei lifted 21 kg on the third lift and 46 kg on the eighth lift.

\n
\n

For that day find how much weight was added after each lift.

\n
[2]
\n
a.i.
\n
\n

For that day find the weight of Sergei’s first lift.

\n
[2]
\n
a.ii.
\n
\n

On that day, Sergei made 12 successive lifts. Find the total combined weight of these lifts.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

5d = 46 − 21  OR  u1 + 2d = 21  and  u1 + 7d = 46     (M1)

\n

Note: Award (M1) for a correct equation in d or for two correct equations in u1 and d.

\n

(d =) 5 (kg)      (A1) (C2)

\n

[2 marks]

\n
a.i.
\n
\n

u1 + 2 × 5 = 21    (M1)

\n

OR

\n

u1 + 7 × 5 = 46    (M1)

\n

Note: Award (M1) for substitution of their d into either of the two equations.

\n

(u=) 11 (kg)     (A1)(ft) (C2)

\n

Note: Follow through from part (a)(i).

\n

[2 marks]

\n
a.ii.
\n
\n

\n\n\n12\n\n2\n\n\n(\n\n2\n×\n11\n+\n\n(\n\n12\n\n1\n\n)\n\n×\n5\n\n)\n\n     (M1)

\n

Note: Award (M1) for correct substitution into arithmetic series formula.

\n

= 462 (kg)     (A1)(ft) (C2)

\n

Note: Follow through from parts (a) and (b).

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ1.T_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

A new café opened and during the first week their profit was $60.

\n

The café’s profit increases by $10 every week.

\n
\n

A new tea-shop opened at the same time as the café. During the first week their profit was also $60.

\n

The tea-shop’s profit increases by 10 % every week.

\n
\n

Calculate the café’s total profit for the first 12 weeks.

\n
[3]
\n
b.
\n
\n

Calculate the tea-shop’s total profit for the first 12 weeks.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

\n\n\n12\n\n2\n\n\n(\n\n2\n×\n60\n+\n11\n×\n10\n\n)\n\n     (M1)(A1)(ft)

\n

Note: Award (M1) for substituting the arithmetic series formula, (A1)(ft) for correct substitution. Follow through from their first term and common difference in part (a).

\n

= ($) 1380     (A1)(ft)(G2)

\n

[3 marks]

\n

 

\n
b.
\n
\n

\n\n\n60\n\n(\n\n\n\n\n1.1\n\n\n12\n\n\n\n\n1\n\n)\n\n\n\n1.1\n\n1\n\n\n     (M1)(A1)(ft)

\n

Note: Award (M1) for substituting the geometric series formula, (A1)(ft) for correct substitution. Follow through from part (c) for their first term and common ratio.

\n

= ($)1280  (1283.05…)     (A1)(ft)(G2)

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
d.
\n
", "question_id": "18M.2.SL.TZ2.T_4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n1\n3\n\n\n\nx\n3\n\n\n+\n\n3\n4\n\n\n\nx\n2\n\n\n\nx\n\n1\n.

\n
\n

The function has one local maximum at \nx\n=\np\n and one local minimum at \nx\n=\nq\n.

\n
\n

Write down the \ny\n-intercept of the graph of \ny\n=\nf\n\n(\nx\n)\n\n.

\n
[1]
\n
b.
\n
\n

Sketch the graph of \ny\n=\nf\n\n(\nx\n)\n\n for −3 ≤ \nx\n ≤ 3 and −4 ≤ \ny\n ≤ 12.

\n
[4]
\n
c.
\n
\n

Determine the range of \nf\n\n(\nx\n)\n\n for \np\n\nx\n\nq\n.

\n
[3]
\n
h.
\n
", "Markscheme": "
\n

−1    (A1)

\n

Note: Accept (0, −1).

\n

[1 mark]

\n
b.
\n
\n

  (A1)(A1)(A1)(A1)

\n

Note: Award (A1) for correct window and axes labels, −3 to 3 should be indicated on the \nx\n-axis and −4 to 12 on the \ny\n-axis.
    (A1)) for smooth curve with correct cubic shape;
    (A1) for \nx\n-intercepts: one close to −3, the second between −1 and 0, and third between 1 and 2; and \ny\n-intercept at approximately −1;
    (A1) for local minimum in the 4th quadrant and maximum in the 2nd quadrant, in approximately correct positions.
Graph paper does not need to be used. If window not given award at most (A0)(A1)(A0)(A1).

\n

[4 marks]

\n
c.
\n
\n

\n\n1.27\n\n\n \n\nf\n\n(\nx\n)\n\n\n1.33\n\n\n\n\n(\n\n\n1.27083\n\n\n\n \n\nf\n\n(\nx\n)\n\n\n1.33333\n\n\n,\n\n\n\n\n\n\n61\n\n\n48\n\n\n\n\n \n\nf\n\n(\nx\n)\n\n\n\n4\n3\n\n\n)\n\n     (A1)(ft)(A1)(ft)(A1)

\n

Note: Award (A1) for −1.27 seen, (A1) for 1.33 seen, and (A1) for correct weak inequalities with their endpoints in the correct order. For example, award (A0)(A0)(A0) for answers like \n5\n\n\n \n\nf\n\n(\nx\n)\n\n\n2\n. Accept \ny\n in place of \nf\n\n(\nx\n)\n\n. Accept alternative correct notation such as [−1.27, 1.33].

\n

Follow through from their \np\n and \nq\n values from part (g) only if their \nf\n\n(\np\n)\n\n and \nf\n\n(\nq\n)\n\n values are between −4 and 12. Award (A0)(A0)(A0) if their values from (g) are given as the endpoints.

\n

[3 marks]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
h.
\n
", "question_id": "19M.2.SL.TZ2.T_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

Solve the equation sec 2 x + 2 tan x = 0 ,   0 x 2 π .

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1

\n

use of sec 2 x = tan 2 x + 1     M1

\n

tan 2 x + 2 tan x + 1 = 0

\n

( tan x + 1 ) 2 = 0     (M1)

\n

tan x = 1     A1

\n

x = 3 π 4 ,   7 π 4     A1A1

\n

METHOD 2

\n

1 cos 2 x + 2 sin x cos x = 0     M1

\n

1 + 2 sin x cos x = 0

\n

sin 2 x = 1     M1A1

\n

2 x = 3 π 2 ,   7 π 2

\n

x = 3 π 4 ,   7 π 4     A1A1

\n

 

\n

Note:     Award A1A0 if extra solutions given or if solutions given in degrees (or both).

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.AHL.TZ1.H_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-9-reciprocal-trig-ratios-and-their-pythagorean-identities-inverse-circular-functions" ] }, { "Question": "
\n

A scientist measures the concentration of dissolved oxygen, in milligrams per litre (y) , in a river. She takes 10 readings at different temperatures, measured in degrees Celsius (x).

\n

The results are shown in the table.

\n

\n

It is believed that the concentration of dissolved oxygen in the river varies linearly with the temperature.

\n
\n

For these data, find Pearson’s product-moment correlation coefficient, r.

\n
[2]
\n
a.i.
\n
\n

For these data, find the equation of the regression line y on x.

\n
[2]
\n
a.ii.
\n
\n

Using the equation of the regression line, estimate the concentration of dissolved oxygen in the river when the temperature is 18 °C.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

−0.974    (−0.973745…)   (A2)

\n

Note: Award (A1) for an answer of 0.974 (minus sign omitted). Award (A1) for an answer of −0.973 (incorrect rounding).

\n

[2 marks]

\n
a.i.
\n
\n

y = −0.365x + 17.9   (y = −0.365032…x + 17.9418…)    (A1)(A1)  (C4)

\n

Note: Award (A1) for −0.365x, (A1) for 17.9. Award at most (A1)(A0) if not an equation or if the values are reversed (eg y = 17.9x −0.365).

\n

[2 marks]

\n
a.ii.
\n
\n

y = −0.365032… × 18 + 17.9418…     (M1)

\n

Note: Award (M1) for correctly substituting 18 into their part (a)(ii).

\n

= 11.4 (11.3712…)     (A1)(ft)  (C2)

\n

Note: Follow through from part (a)(ii).

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ1.T_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Let \nz\n=\n1\n\ncos\n\n2\nθ\n\n\ni\n\nsin\n\n2\nθ\n,\n\n \n\nz\n\n\nC\n\n,\n\n \n\n0\n\nθ\n\nπ\n.

\n
\n

Solve \n2\nsin\n\n(\nx\n+\n\n60\n\n\n)\n=\ncos\n\n(\nx\n+\n\n30\n\n\n)\n,\n\n \n\n\n0\n\n\n\nx\n\n\n180\n\n\n.

\n
[5]
\n
a.
\n
\n

Show that \nsin\n\n\n105\n\n\n+\ncos\n\n\n105\n\n\n=\n\n1\n\n\n2\n\n\n\n.

\n
[3]
\n
b.
\n
\n

Find the modulus and argument of \nz\n in terms of \nθ\n. Express each answer in its simplest form.

\n
[9]
\n
c.i.
\n
\n

Hence find the cube roots of \nz\n in modulus-argument form.

\n
[5]
\n
c.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n2\nsin\n\n(\nx\n+\n\n60\n\n\n)\n=\ncos\n\n(\nx\n+\n\n30\n\n\n)\n

\n

\n2\n(\nsin\n\nx\ncos\n\n\n60\n\n\n+\ncos\n\nx\nsin\n\n\n60\n\n\n)\n=\ncos\n\nx\ncos\n\n\n30\n\n\n\nsin\n\nx\nsin\n\n\n30\n\n\n     (M1)(A1)

\n

\n2\nsin\n\nx\n×\n\n1\n2\n\n+\n2\ncos\n\nx\n×\n\n\n\n3\n\n\n2\n\n=\ncos\n\nx\n×\n\n\n\n3\n\n\n2\n\n\nsin\n\nx\n×\n\n1\n2\n\n     A1

\n

\n\n\n3\n2\n\nsin\n\nx\n=\n\n\n\n\n3\n\n\n2\n\ncos\n\nx\n

\n

\n\ntan\n\nx\n=\n\n\n1\n\n\n3\n\n\n\n     M1

\n

\n\nx\n=\n\n150\n\n\n     A1

\n

[5 marks]

\n
a.
\n
\n

EITHER

\n

choosing two appropriate angles, for example 60° and 45°     M1

\n

\nsin\n\n\n105\n\n\n=\nsin\n\n\n60\n\n\ncos\n\n\n45\n\n\n+\ncos\n\n\n60\n\n\nsin\n\n\n45\n\n\n and

\n

\ncos\n\n\n105\n\n\n=\ncos\n\n\n60\n\n\ncos\n\n\n45\n\n\n\nsin\n\n\n60\n\n\nsin\n\n\n45\n\n\n     (A1)

\n

\nsin\n\n\n105\n\n\n+\ncos\n\n\n105\n\n\n=\n\n\n\n3\n\n\n2\n\n×\n\n1\n\n\n2\n\n\n\n+\n\n1\n2\n\n×\n\n1\n\n\n2\n\n\n\n+\n\n1\n2\n\n×\n\n1\n\n\n2\n\n\n\n\n\n\n\n3\n\n\n2\n\n×\n\n1\n\n\n2\n\n\n\n     A1

\n

\n=\n\n1\n\n\n2\n\n\n\n     AG

\n

OR

\n

attempt to square the expression     M1

\n

\n\n(\nsin\n\n\n105\n\n\n+\ncos\n\n\n105\n\n\n\n)\n2\n\n\n=\n\n\nsin\n2\n\n\n\n105\n\n\n+\n2\nsin\n\n\n105\n\n\ncos\n\n\n105\n\n\n+\n\n\ncos\n2\n\n\n\n105\n\n\n

\n

\n\n(\nsin\n\n\n105\n\n\n+\ncos\n\n\n105\n\n\n\n)\n2\n\n\n=\n1\n+\nsin\n\n\n210\n\n\n     A1

\n

\n=\n\n1\n2\n\n     A1

\n

\nsin\n\n\n105\n\n\n+\ncos\n\n\n105\n\n\n=\n\n1\n\n\n2\n\n\n\n   AG

\n

 

\n

[3 marks]

\n
b.
\n
\n

EITHER

\n

\nz\n=\n(\n1\n\ncos\n\n2\nθ\n)\n\n\ni\n\nsin\n\n2\nθ\n

\n

\n\n|\nz\n|\n\n=\n\n\n\n\n(\n1\n\ncos\n\n2\nθ\n)\n\n2\n\n\n+\n\n\n\n(\nsin\n\n2\nθ\n)\n\n2\n\n\n\n     M1

\n

\n\n|\nz\n|\n\n=\n\n1\n\n2\ncos\n\n2\nθ\n+\n\n\n\ncos\n\n2\n\n\n2\nθ\n+\n\n\n\nsin\n\n2\n\n\n2\nθ\n\n     A1

\n

\n=\n\n2\n\n\n(\n1\n\ncos\n\n2\nθ\n)\n\n     A1

\n

\n=\n\n2\n(\n2\n\n\n\nsin\n\n2\n\n\nθ\n)\n\n

\n

\n=\n2\nsin\n\nθ\n     A1

\n

let \narg\n\n(\nz\n)\n=\nα\n

\n

\ntan\n\nα\n=\n\n\n\nsin\n\n2\nθ\n\n\n1\n\ncos\n\n2\nθ\n\n\n     M1

\n

\n=\n\n\n\n2\nsin\n\nθ\ncos\n\nθ\n\n\n2\n\n\n\nsin\n\n2\n\n\nθ\n\n\n     (A1)

\n

\n=\n\ncot\n\nθ\n     A1

\n

\narg\n\n(\nz\n)\n=\nα\n=\n\narctan\n\n\n(\n\ntan\n\n\n(\n\n\nπ\n2\n\n\nθ\n\n)\n\n\n)\n\n     A1

\n

\n=\nθ\n\n\nπ\n2\n\n     A1

\n

OR

\n

\nz\n=\n(\n1\n\ncos\n\n2\nθ\n)\n\n\ni\n\nsin\n\n2\nθ\n

\n

\n=\n2\n\n\nsin\n2\n\n\nθ\n\n2\n\ni\n\nsin\n\nθ\ncos\n\nθ\n     M1A1

\n

\n=\n2\nsin\n\nθ\n(\nsin\n\nθ\n\n\ni\n\ncos\n\nθ\n)\n     (A1)

\n

\n=\n\n2\n\ni\n\nsin\n\nθ\n(\ncos\n\nθ\n+\n\ni\n\nsin\n\nθ\n)\n     M1A1

\n

\n=\n2\nsin\n\nθ\n\n(\n\ncos\n\n\n(\n\nθ\n\n\nπ\n2\n\n\n)\n\n+\n\ni\n\nsin\n\n\n(\n\nθ\n\n\nπ\n2\n\n\n)\n\n\n)\n\n     M1A1

\n

\n\n|\nz\n|\n\n=\n2\nsin\n\nθ\n     A1

\n

\narg\n\n(\nz\n)\n=\nθ\n\n\nπ\n2\n\n     A1

\n

[9 marks]

\n
c.i.
\n
\n

attempt to apply De Moivre’s theorem     M1

\n

\n\n(\n1\n\ncos\n\n2\nθ\n\n\ni\n\nsin\n\n2\nθ\n\n)\n\n\n1\n3\n\n\n\n\n=\n\n\n2\n\n\n1\n3\n\n\n\n\n\n(\nsin\n\nθ\n\n)\n\n\n1\n3\n\n\n\n\n\n[\n\ncos\n\n\n(\n\n\n\nθ\n\n\nπ\n2\n\n+\n2\nn\nπ\n\n3\n\n\n)\n\n+\n\ni\n\nsin\n\n\n(\n\n\n\nθ\n\n\nπ\n2\n\n+\n2\nn\nπ\n\n3\n\n\n)\n\n\n]\n\n     A1A1A1

\n

 

\n

Note:     A1 for modulus, A1 for dividing argument of \nz\n by 3 and A1 for \n2\nn\nπ\n.

\n

 

\n

Hence cube roots are the above expression when \nn\n=\n\n1\n,\n\n \n\n0\n,\n\n \n\n1\n. Equivalent forms are acceptable.     A1

\n

[5 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "17M.1.AHL.TZ2.H_11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-10-compound-angle-identities" ] }, { "Question": "
\n

Consider the numbers \np\n=\n2.78\n×\n\n\n10\n\n11\n\n\n\n and \nq\n=\n3.12\n×\n\n\n10\n\n\n3\n\n\n\n.

\n
\n

Calculate p q 3 . Give your full calculator display.

\n
[2]
\n
a.
\n
\n

Write down your answer to part (a) correct to two decimal places;

\n
[1]
\n
b.i.
\n
\n

Write down your answer to part (a) correct to three significant figures.

\n
[1]
\n
b.ii.
\n
\n

Write your answer to part (b)(ii) in the form a × 10 k , where 1 a < 10 ,   k Z .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

2.78 × 10 11 3.12 × 10 3 3 OR 8.91025 × 10 13 3     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into given expression.

\n

 

\n

44664.59503     (A1)     (C2)

\n

 

\n

Note:     Award (A1) for a correct answer with at least 8 digits.

\n

Accept 44664.5950301.

\n

 

\n

[2 marks]

\n
a.
\n
\n

44664.60     (A1)(ft)     (C1)

\n

 

\n

Note:     For a follow through mark, the answer to part (a) must be to at least 3 decimal places.

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

44700     (A1)(ft)     (C1)

\n

 

\n

Notes:     Answer to part (a) must be to at least 4 significant figures.

\n

Accept any equivalent notation which is correct to 3 significant figures.

\n

For example 447 × 10 2 or 44.7 × 10 3 .

\n

Follow through from part (a).

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

4.47 × 10 4     (A1)(ft)(A1)(ft)     (C2)

\n

 

\n

Notes:     Award (A1)(ft) for 4.47 and (A1)(ft) for 10 4 .

\n

Award (A0)(A0) for answers such as 44.7 × 10 3 .

\n

Follow through from part (b)(ii) only.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-1-using-standard-form" ] }, { "Question": "
\n

Show that ( sin x + cos x ) 2 = 1 + sin 2 x .

\n
[2]
\n
a.
\n
\n

Show that sec 2 x + tan 2 x = cos x + sin x cos x sin x .

\n
[4]
\n
b.
\n
\n

Hence or otherwise find  0 π 6 ( sec 2 x + tan 2 x ) d x  in the form  ln ( a + b ) where a b Z .

\n
[9]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

( sin x + cos x ) 2 = si n 2 x + 2 sin x cos x + co s 2 x       M1A1

\n

Note: Do not award the M1 for just  si n 2 x + co s 2 x .

\n

Note: Do not award A1 if correct expression is followed by incorrect working.

\n

= 1 + sin 2 x       AG

\n

[2 marks]

\n
a.
\n
\n

sec 2 x + tan 2 x = 1 cos 2 x + sin 2 x cos 2 x      M1

\n

Note: M1 is for an attempt to change both terms into sine and cosine forms (with the same argument) or both terms into functions of tan x .

\n

= 1 + sin 2 x cos 2 x

\n

= ( sin x + cos x ) 2 co s 2 x si n 2 x          A1A1

\n

Note: Award A1 for numerator, A1 for denominator.

\n

= ( sin x + cos x ) 2 ( cos x sin x ) ( cos x + sin x )      M1

\n

= cos x + sin x cos x sin x       AG

\n

Note: Apply MS in reverse if candidates have worked from RHS to LHS.

\n

Note: Alternative method using tan 2 x and sec 2 x in terms of tan x .

\n

[4 marks]

\n
b.
\n
\n

METHOD 1

\n

0 π 6 ( cos x + sin x cos x sin x ) d x        A1

\n

Note: Award A1 for correct expression with or without limits.

\n

EITHER

\n

= [ ln ( cos x sin x ) ] 0 π 6   or   [ ln ( cos x sin x ) ] π 6 0        (M1)A1A1

\n

Note: Award M1 for integration by inspection or substitution, A1 for  ln ( cos x sin x ) A1 for completely correct expression including limits.

\n

= ln ( cos π 6 sin π 6 ) + ln ( cos 0 sin 0 )        M1

\n

Note: Award M1 for substitution of limits into their integral and subtraction.

\n

= ln ( 3 2 1 2 )        (A1)

\n

OR

\n

let  u = cos x sin x        M1

\n

d u d x = sin x cos x = ( sin x + cos x )

\n

1 3 2 1 2 ( 1 u ) d u        A1A1

\n

Note: Award A1 for correct limits even if seen later, A1 for integral.

\n

= [ ln u ] 1 3 2 1 2   or   [ ln u ] 3 2 1 2 1        A1

\n

= ln ( 3 2 1 2 ) (  + ln 1 )        M1

\n

THEN

\n

= ln ( 2 3 1 )

\n

Note: Award M1 for both putting the expression over a common denominator and for correct use of law of logarithms.

\n

= ln ( 1 + 3 )        (M1)A1

\n

 

\n

METHOD 2

\n

[ 1 2 ln ( tan 2 x + sec 2 x ) 1 2 ln ( cos 2 x ) ] 0 π 6       A1A1

\n

= 1 2 ln ( 3 + 2 ) 1 2 ln ( 1 2 ) 0        A1A1(A1)

\n

= 1 2 ln ( 4 + 2 3 )        M1

\n

= 1 2 ln ( ( 1 + 3 ) 2 )        M1A1

\n

= ln ( 1 + 3 )       A1

\n

 

\n

 

\n

[9 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.AHL.TZ1.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-10-compound-angle-identities" ] }, { "Question": "
\n

Tomás is playing with sticks and he forms the first three diagrams of a pattern. These diagrams are shown below.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/05\"

\n

Tomás continues forming diagrams following this pattern.

\n
\n

Tomás forms a total of 24 diagrams.

\n
\n

Diagram \nn\n is formed with 52 sticks. Find the value of \nn\n.

\n
[3]
\n
a.
\n
\n

Find the total number of sticks used by Tomás for all 24 diagrams.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n4\n+\n3\n(\nn\n\n1\n)\n=\n52\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substitution into the formula of the \nn\nth term of an arithmetic sequence, (A1) for correct substitution.

\n

 

\n

\nn\n=\n17\n     (A1)     (C3)

\n

[3 marks]

\n
a.
\n
\n

\n\n\n24\n\n2\n\n(\n2\n×\n4\n+\n23\n×\n3\n)\n\n\n\n\nOR\n\n\n\n\n\n\n24\n\n2\n\n(\n4\n+\n73\n)\n     (M1)(A1)(ft)

\n

 

\n

Notes:     Award (M1) for substitution into the sum of the first \nn\n terms of an arithmetic sequence formula, (A1)(ft) for their correct substitution, consistent with part (a).

\n

 

\n

924     (A1)(ft)     (C3)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ2.T_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The graph of the quadratic function \nf\n(\nx\n)\n=\nc\n+\nb\nx\n\n\n\nx\n2\n\n\n intersects the \nx\n-axis at the point \n\nA\n\n(\n\n1\n,\n\n \n\n0\n)\n and has its vertex at the point \n\nB\n\n(\n3\n,\n\n \n\n16\n)\n.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/09\"

\n
\n

Write down the equation of the axis of symmetry for this graph.

\n
[2]
\n
a.
\n
\n

Find the value of \nb\n.

\n
[2]
\n
b.
\n
\n

Write down the range of \nf\n(\nx\n)\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nx\n=\n3\n    (A1)(A1)     (C2)

\n

 

\n

Note:     Award (A1) for \nx\n=\n constant, (A1) for the constant being 3.

\n

The answer must be an equation.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n\n\n\nb\n\n\n2\n(\n\n1\n)\n\n\n=\n3\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into axis of symmetry formula.

\n

 

\n

OR

\n

\nb\n\n2\nx\n=\n0\n    (M1)

\n

 

\n

Note:     Award (M1) for correctly differentiating and equating to zero.

\n

 

\n

OR

\n

\nc\n+\nb\n(\n\n1\n)\n\n\n(\n\n1\n\n)\n2\n\n\n=\n0\n (or equivalent)

\n

\nc\n+\nb\n(\n3\n)\n\n\n(\n3\n\n)\n2\n\n\n=\n16\n (or equivalent)     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution of \n(\n\n1\n,\n\n \n\n0\n)\n and \n(\n3\n,\n\n \n\n16\n)\n in the original quadratic function.

\n

 

\n

\n(\nb\n=\n)\n\n \n\n6\n    (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n(\n\n\n,\n\n 16]\n\n OR \n]\n\n\n,\n\n \n\n16\n]\n     (A1)(A1)

\n

 

\n

Note:     Award (A1) for two correct interval endpoints, (A1) for left endpoint excluded and right endpoint included.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.1.SL.TZ0.T_9", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

The company Snakezen’s Ladders makes ladders of different lengths. All the ladders that the company makes have the same design such that:

\n

the first rung is 30 cm from the base of the ladder,

\n

the second rung is 57 cm from the base of the ladder,

\n

the distance between the first and second rung is equal to the distance between all adjacent rungs on the ladder.

\n

The ladder in the diagram was made by this company and has eleven equally spaced rungs.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/05\"

\n
\n

Find the distance from the base of this ladder to the top rung.

\n
[3]
\n
a.
\n
\n

The company also makes a ladder that is 1050 cm long.

\n

Find the maximum number of rungs in this 1050 cm long ladder.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n30\n+\n(\n11\n\n1\n)\n×\n27\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substituted arithmetic sequence formula, (A1) for correct substitutions.

\n

 

\n

\n=\n300\n\n (cm)\n\n     (A1)     (C3)

\n

 

\n

Note:     Units are not required.

\n

 

\n

[3 marks]

\n
a.
\n
\n

\n1050\n\n30\n+\n(\nn\n\n1\n)\n×\n27\n     (M1)(A1)(ft)

\n

 

\n

Note:     Award (M1) for substituted arithmetic sequence formula \n\n1050\n, accept an equation, (A1) for correct substitutions.

\n

 

\n

\nn\n=\n38\n     (A1)(ft)     (C3)

\n

 

\n

Note:     Follow through from their 27 in part (a). The answer must be an integer and rounded down.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ1.T_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\n\n\ne\n\nx\n\n\n\n\ncos\n\n\n\n\n2\n\n\nx\n, where 0 ≤ \nx\n ≤ 5. The curve \ny\n=\nf\n\n(\nx\n)\n\n is shown on the following graph which has local maximum points at A and C and touches the \nx\n-axis at B and D.

\n

\n
\n

Use integration by parts to show that e x cos 2 x d x = 2 e x 5 sin 2 x + e x 5 cos 2 x + c ,   c R .

\n
[5]
\n
a.
\n
\n

Hence, show that e x cos 2 x d x = e x 5 sin 2 x + e x 10 cos 2 x + e x 2 + c ,   c R .

\n
[3]
\n
b.
\n
\n

Find the x -coordinates of A and of C , giving your answers in the form  a + arctan b , where  a b R .

\n
[6]
\n
c.
\n
\n

Find the area enclosed by the curve and the x -axis between B and D, as shaded on the diagram.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1

\n

attempt at integration by parts with  u = e x ,   d v d x = cos 2 x       M1

\n

e x cos 2 x d x = e x 2 sin 2 x d x e x 2 sin 2 x d x       A1

\n

= e x 2 sin 2 x 1 2 ( e x 2 cos 2 x + e x 2 cos 2 x )       M1A1

\n

e x 2 sin 2 x + e x 4 cos 2 x 1 4 e x cos 2 x d x

\n

5 4 e x cos 2 x d x = e x 2 sin 2 x + e x 4 cos 2 x       M1

\n

e x cos 2 x d x = 2 e x 5 sin 2 x + e x 5 cos 2 x ( + c )     AG

\n

 

\n

 

\n

METHOD 2

\n

attempt at integration by parts with u = cos 2 x d v d x = e x       M1

\n

e x cos 2 x d x = e x cos 2 x + 2 e x sin 2 x d x       A1

\n

= e x cos 2 x + 2 ( e x sin 2 x 2 e x cos 2 x d x )       M1A1

\n

= e x cos 2 x + 2 e x sin 2 x 4 e x cos 2 x d x

\n

5 e x cos 2 x d x = e x cos 2 x + 2 e x sin 2 x       M1

\n

e x cos 2 x d x = 2 e x 5 sin 2 x + e x 5 cos 2 x ( + c )    AG

\n

 

\n

METHOD 3

\n

attempt at use of table      M1

\n

eg

\n

      A1A1 

\n

Note: A1 for first 2 lines correct, A1 for third line correct.

\n

e x cos 2 x d x = e x cos 2 x + 2 e x sin 2 x 4 e x cos 2 x d x       M1

\n

5 e x cos 2 x d x = e x cos 2 x + 2 e x sin 2 x       M1

\n

e x cos 2 x d x = 2 e x 5 sin 2 x + e x 5 cos 2 x ( + c )    AG

\n

 

\n

[5 marks]

\n
a.
\n
\n

e x co s 2 x d x = e x 2 ( cos 2 x + 1 ) d x      M1A1

\n

= 1 2 ( 2 e x 5 sin 2 x + e x 5 cos 2 x ) + e x 2       A1

\n

= e x 5 sin 2 x + e x 10 cos 2 x + e x 2 ( + c )       AG

\n

Note: Do not accept solutions where the RHS is differentiated.

\n

 

\n

[3 marks]

\n
b.
\n
\n

f ( x ) = e x co s 2 x 2 e x sin x cos x       M1A1

\n

Note: Award M1 for an attempt at both the product rule and the chain rule.

\n

e x cos x ( cos x 2 sin x ) = 0       (M1)

\n

Note: Award M1 for an attempt to factorise  cos x  or divide by  cos x ( cos x 0 ) .

\n

discount  cos x = 0  (as this would also be a zero of the function)

\n

cos x 2 sin x = 0

\n

tan x = 1 2       (M1)

\n

x = arctan ( 1 2 ) (at A) and  x = π + arctan ( 1 2 )  (at C)      A1A1

\n

Note: Award A1 for each correct answer. If extra values are seen award A1A0.

\n

 

\n

[6 marks]

\n
c.
\n
\n

 

\n

cos x = 0 x = π 2 or  3 π 2       A1

\n

Note: The A1may be awarded for work seen in part (c).

\n

π 2 3 π 2 ( e x co s 2 x ) d x = [ e x 5 sin 2 x + e x 10 cos 2 x + e x 2 ] π 2 3 π 2       M1

\n

= ( e 3 π 2 10 + e 3 π 2 2 ) ( e π 2 10 + e π 2 2 ) ( = 2 e 3 π 2 5 2 e π 2 5 )       M1(A1)A1

\n

Note: Award M1 for substitution of the end points and subtracting, (A1) for  sin 3 π = sin π = 0 and  cos 3 π = cos π = 1  and A1 for a completely correct answer.

\n

 

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18N.1.AHL.TZ0.H_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-7-the-second-derivative" ] }, { "Question": "
\n

A survey was carried out to investigate the relationship between a person’s age in years ( \na\n) and the number of hours they watch television per week (\nh\n). The scatter diagram represents the results of the survey.

\n

\"N17/5/MATSD/SP1/ENG/TZ0/05\"

\n

The mean age of the people surveyed was 50.

\n

For these results, the equation of the regression line \nh\n on \na\n is \nh\n=\n0.22\na\n+\n15\n.

\n
\n

Find the mean number of hours that the people surveyed watch television per week.

\n
[2]
\n
a.
\n
\n

Draw the regression line on the scatter diagram.

\n
[2]
\n
b.
\n
\n

By placing a tick (✔) in the correct box, determine which of the following statements is true:

\n

\"N17/5/MATSD/SP1/ENG/TZ0/05.c\"

\n
[1]
\n
c.
\n
\n

Diogo is 18 years old. Give a reason why the regression line should not be used to estimate the number of hours Diogo watches television per week.

\n
[1]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n0.22\n(\n50\n)\n+\n15\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution of 50 into equation of the regression line.

\n

 

\n

\n(\n=\n)\n\n \n\n26\n     (A1)     (C2)

\n

OR

\n

\n\n\n655\n\n\n25\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correctly summing the \nh\n values of the points, and dividing by 25.

\n

 

\n

\n(\n=\n)\n\n \n\n26.2\n     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

line through \n(\n50\n,\n\n \n\n26\n±\n1\n)\n and \n(\n0\n,\n\n \n\n15\n)\n     (A1)(ft)(A1)     (C2)

\n

 

\n

Note: Award (A1)(ft) for a straight line through (50, their \n\n\nh\n¯\n\n\n), and (A1) for the line intercepting the \ny\n-axis at \n(\n0\n,\n\n \n\n15\n)\n; this may need to be extrapolated. Follow through from part (a). Award at most (A0)(A1) if the line is not drawn with a ruler.

\n

 

\n

[2 marks]

\n
b.
\n
\n

\"N17/5/MATSD/SP1/ENG/TZ0/05.c/M\"     (A1) (C1)

\n

 

\n

Note:     Award (A0) if more than one tick (✔) is seen.

\n

 

\n

[1 mark]

\n
c.
\n
\n

18 is less than the lowest age in the survey OR extrapolation.     (A1)     (C1)

\n

 

\n

Note:     Accept equivalent statements.

\n

 

\n

[1 mark]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17N.1.SL.TZ0.T_5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\ntan\n\n\n(\n\nx\n+\nπ\n\n)\n\n\ncos\n\n\n(\n\nx\n\n\nπ\n2\n\n\n)\n\n where \n0\n<\nx\n<\n\nπ\n2\n\n.

\n

Express \nf\n\n(\nx\n)\n\n in terms of sin \nx\n and cos \nx\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\ntan\n\n\n(\n\nx\n+\nπ\n\n)\n\n=\ntan\n\nx\n\n(\n\n=\n\n\n\nsin\n\n\nx\n\n\n\ncos\n\n\nx\n\n\n\n)\n\n     (M1)A1

\n

\n\ncos\n\n\n(\n\nx\n\n\nπ\n2\n\n\n)\n\n=\n\nsin\n\n\nx\n     (M1)A1

\n

Note: The two M1s can be awarded for observation or for expanding.

\n

\n\ntan\n\n\n(\n\nx\n+\nπ\n\n)\n\n=\n\ncos\n\n\n(\n\nx\n\n\nπ\n2\n\n\n)\n\n=\n\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nx\n\n\n\ncos\n\n\nx\n\n\n     A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.AHL.TZ1.H_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-10-compound-angle-identities" ] }, { "Question": "
\n

A comet orbits the Sun and is seen from Earth every 37 years. The comet was first seen from Earth in the year 1064.

\n
\n

Find the year in which the comet was seen from Earth for the fifth time.

\n
[3]
\n
a.
\n
\n

Determine how many times the comet has been seen from Earth up to the year 2014.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n1064\n+\n(\n5\n\n1\n)\n×\n37\n    (M1)(A1)

\n

 

\n

Note:     Award (M1) for substituted arithmetic sequence formula, (A1) for correct substitution.

\n

 

\n

\n=\n1212\n    (A1)     (C3)

\n

[3 marks]

\n
a.
\n
\n

\n2014\n>\n1064\n+\n(\nn\n\n1\n)\n×\n37\n    (M1)

\n

 

\n

Note:     Award (M1) for a correct substitution into arithmetic sequence formula.

\n

Accept an equation.

\n

 

\n

\n(\nn\n<\n)\n\n \n\n26.6756\n\n    (A1)

\n

26 (times)     (A1)     (C3)

\n

 

\n

Note:     Award the final (A1) for the correct rounding down of their unrounded answer.

\n

 

\n

OR

\n

\n2014\n>\n1064\n+\n37\nt\n    (M1)

\n

 

\n

Note:     Award (M1) for a correct substitution into a linear model (where \nt\n=\nn\n\n1\n).

\n

Accept an equation or weak inequality.

\n

Accept \n\n\n2014\n\n1064\n\n\n37\n\n\n for     (M1).

\n

 

\n

\n(\nt\n<\n)\n\n \n\n25.6756\n\n    (A1)

\n

 

\n

26 (times)     (A1)     (C3)

\n

 

\n

Note:     Award the final (A1) for adding 1 to the correct rounding down of their unrounded answer.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_13", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Violeta plans to grow flowers in a rectangular plot. She places a fence to mark out the perimeter of the plot and uses 200 metres of fence. The length of the plot is \nx\n metres.

\n

\"M17/5/MATSD/SP2/ENG/TZ2/05\"

\n
\n

Violeta places the fence so that the area of the plot is maximized.

\n
\n

By selling her flowers, Violeta earns 2 Bulgarian Levs (BGN) per square metre of the plot.

\n
\n

Show that the width of the plot, in metres, is given by 100 x .

\n
[1]
\n
a.
\n
\n

Write down the area of the plot in terms of x .

\n
[1]
\n
b.
\n
\n

Find the value of x that maximizes the area of the plot.

\n
[2]
\n
c.
\n
\n

Show that Violeta earns 5000 BGN from selling the flowers grown on the plot.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

200 2 x 2 (or equivalent)     (M1)

\n

OR

\n

2 x + 2 y = 200 (or equivalent)     (M1)

\n

 

\n

Note:     Award (M1) for a correct expression leading to 100 x (the 100 x does not need to be seen). The 200 must be seen for the (M1) to be awarded. Do not accept 100 x substituted in the perimeter of the rectangle formula.

\n

 

\n

100 x     (AG)

\n

[1 mark]

\n
a.
\n
\n

( area = )   x ( 100 x ) OR x 2 + 100 x (or equivalent)     (A1)

\n

[1 mark]

\n
b.
\n
\n

x = 100 2 OR 2 x + 100 = 0 OR graphical method     (M1)

\n

 

\n

Note:     Award (M1) for use of axis of symmetry formula or first derivative equated to zero or a sketch graph.

\n

 

\n

x = 50     (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from part (b), provided x is positive and less than 100.

\n

 

\n

[2 marks]

\n
c.
\n
\n

50 ( 100 50 ) × 2     (M1)(M1)

\n

 

\n

Note:     Award (M1) for substituting their x into their formula for area (accept “ 50 × 50 ” for the substituted formula), and (M1) for multiplying by 2. Award at most (M0)(M1) if their calculation does not lead to 5000 (BGN), although the 5000 (BGN) does not need to be seen explicitly.

\n

Substitution of 50 into area formula may be seen in part (c).

\n

 

\n

5000 (BGN)     (AG)

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.2.SL.TZ2.T_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

In the following Argand diagram the point A represents the complex number 1 + 4 i and the point B represents the complex number 3 + 0 i . The shape of ABCD is a square. Determine the complex numbers represented by the points C and D.

\n

\"M17/5/MATHL/HP1/ENG/TZ2/05\"

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

C represents the complex number 1 2 i      A2

\n

D represents the complex number 3 + 2 i      A2

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.AHL.TZ2.H_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

Consider the functions \nf\n and \ng\n defined on the domain \n0\n<\nx\n<\n2\nπ\n by \nf\n\n(\nx\n)\n\n=\n3\n\n\ncos\n\n\n2\nx\n and \ng\n\n(\nx\n)\n\n=\n4\n\n11\n\n\ncos\n\n\nx\n.

\n

The following diagram shows the graphs of \ny\n=\nf\n\n(\nx\n)\n\n and \ny\n=\ng\n\n(\nx\n)\n\n

\n

\n
\n

Find the x -coordinates of the points of intersection of the two graphs.

\n
[6]
\n
a.
\n
\n

Find the exact area of the shaded region, giving your answer in the form  p π + q 3 , where p q Q .

\n
[5]
\n
b.
\n
\n

At the points A and B on the diagram, the gradients of the two graphs are equal.

\n

Determine the y -coordinate of A on the graph of g .

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

3 cos 2 x = 4 11 cos x

\n

attempt to form a quadratic in  cos x      M1

\n

3 ( 2 co s 2 x 1 ) = 4 11 cos x      A1

\n

( 6 co s 2 x + 11 cos x 7 = 0 )

\n

valid attempt to solve their quadratic     M1

\n

( 3 cos x + 7 ) ( 2 cos x 1 ) = 0

\n

cos x = 1 2      A1

\n

x = π 3 , 5 π 3      A1A1

\n

Note: Ignore any “extra” solutions.

\n

[6 marks]

\n
a.
\n
\n

consider (±)  π 3 5 π 3 ( 4 11 cos x 3 cos 2 x ) d x      M1

\n

= ( ± ) [ 4 x 11 sin x 3 2 sin 2 x ] π 3 5 π 3      A1

\n

Note: Ignore lack of or incorrect limits at this stage.

\n

attempt to substitute their limits into their integral     M1

\n

= 20 π 3 11 sin 5 π 3 3 2 sin 10 π 3 ( 4 π 3 11 sin π 3 3 2 sin 2 π 3 )

\n

= 16 π 3 + 11 3 2 + 3 3 4 + 11 3 2 + 3 3 4

\n

= 16 π 3 + 25 3 2      A1A1

\n

[5 marks]

\n
b.
\n
\n

attempt to differentiate both functions and equate     M1

\n

6 sin 2 x = 11 sin x      A1

\n

attempt to solve for x      M1

\n

11 sin x + 12 sin x cos x = 0

\n

sin x ( 11 + 12 cos x ) = 0

\n

cos x = 11 12 ( or sin x = 0 )      A1

\n

y = 4 11 ( 11 12 )      M1

\n

y = 169 12 ( = 14 1 12 )      A1

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.AHL.TZ2.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

Maria owns a cheese factory. The amount of cheese, in kilograms, Maria sells in one week, \nQ\n, is given by

\n

\nQ\n=\n882\n\n45\np\n,

\n

where \np\n is the price of a kilogram of cheese in euros (EUR).

\n
\n

Maria earns \n(\np\n\n6.80\n)\n\n EUR\n\n for each kilogram of cheese sold.

\n
\n

To calculate her weekly profit \nW\n, in EUR, Maria multiplies the amount of cheese she sells by the amount she earns per kilogram.

\n
\n

Write down how many kilograms of cheese Maria sells in one week if the price of a kilogram of cheese is 8 EUR.

\n
[1]
\n
a.
\n
\n

Find how much Maria earns in one week, from selling cheese, if the price of a kilogram of cheese is 8 EUR.

\n
[2]
\n
b.
\n
\n

Write down an expression for \nW\n in terms of \np\n.

\n
[1]
\n
c.
\n
\n

Find the price, \np\n, that will give Maria the highest weekly profit.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

522 (kg)     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

\n522\n(\n8\n\n6.80\n)\n or equivalent     (M1)

\n

 

\n

Note:     Award (M1) for multiplying their answer to part (a) by \n(\n8\n\n6.80\n)\n.

\n

 

\n

626 (EUR) (626.40)     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n(\nW\n=\n)\n\n \n\n(\n882\n\n45\np\n)\n(\np\n\n6.80\n)\n     (A1)

\n

OR

\n

\n(\nW\n=\n)\n\n45\n\n\np\n2\n\n\n+\n1188\np\n\n5997.6\n     (A1)     (C1)

\n

[1 mark]

\n
c.
\n
\n

sketch of \nW\n with some indication of the maximum     (M1)

\n

OR

\n

\n\n90\np\n+\n1188\n=\n0\n     (M1)

\n

 

\n

Note:     Award (M1) for equating the correct derivative of their part (c) to zero.

\n

 

\n

OR

\n

\n(\np\n=\n)\n\n \n\n\n\n\n1188\n\n\n2\n×\n(\n\n45\n)\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into the formula for axis of symmetry.

\n

 

\n

\n(\np\n=\n)\n\n \n\n13.2\n\n (EUR)\n\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from their part (c), if the value of \np\n is such that \n6.80\n<\np\n<\n19.6\n.

\n

 

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17N.1.SL.TZ0.T_15", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Determine the roots of the equation \n\n(\nz\n+\n2\n\ni\n\n\n)\n3\n\n\n=\n216\n\ni\n\n, \nz\n\n\nC\n\n, giving the answers in the form \nz\n=\na\n\n3\n\n+\nb\n\ni\n\n where \na\n,\n\n \n\nb\n\n\nZ\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n216\n\ni\n\n=\n216\n\n(\n\ncos\n\n\nπ\n2\n\n+\n\ni\n\nsin\n\n\nπ\n2\n\n\n)\n\n     A1

\n

\nz\n+\n2\n\ni\n\n=\n\n\n216\n\n3\n\n\n\n\n(\n\ncos\n\n\n(\n\n\nπ\n2\n\n+\n2\nπ\nk\n\n)\n\n=\n\ni\n\nsin\n\n\n(\n\n\nπ\n2\n\n+\n2\nπ\nk\n\n)\n\n\n)\n\n\n\n1\n3\n\n\n\n\n     (M1)

\n

\nz\n+\n2\n\ni\n\n=\n6\n\n(\n\ncos\n\n\n(\n\n\nπ\n6\n\n+\n\n\n2\nπ\nk\n\n3\n\n\n)\n\n+\n\ni\n\nsin\n\n\n(\n\n\nπ\n6\n\n+\n\n\n2\nπ\nk\n\n3\n\n\n)\n\n\n)\n\n     A1

\n

\n\n\nz\n1\n\n\n+\n2\n\ni\n\n=\n6\n\n(\n\ncos\n\n\nπ\n6\n\n+\n\ni\n\nsin\n\n\nπ\n6\n\n\n)\n\n=\n6\n\n(\n\n\n\n\n3\n\n\n2\n\n+\n\n\ni\n\n2\n\n\n)\n\n=\n3\n\n3\n\n+\n3\n\ni\n\n

\n

\n\n\nz\n2\n\n\n+\n2\n\ni\n\n=\n6\n\n(\n\ncos\n\n\n\n5\nπ\n\n6\n\n+\n\ni\n\nsin\n\n\n\n5\nπ\n\n6\n\n\n)\n\n=\n6\n\n(\n\n\n\n\n\n3\n\n\n2\n\n+\n\n\ni\n\n2\n\n\n)\n\n=\n\n3\n\n3\n\n+\n3\n\ni\n\n

\n

\n\n\nz\n3\n\n\n+\n2\n\ni\n\n=\n6\n\n(\n\ncos\n\n\n\n3\nπ\n\n2\n\n+\n\ni\n\nsin\n\n\n\n3\nπ\n\n2\n\n\n)\n\n=\n\n6\n\ni\n\n     A2

\n

 

\n

Note:     Award A1A0 for one correct root.

\n

 

\n

so roots are \n\n\nz\n1\n\n\n=\n3\n\n3\n\n+\n\ni, \n\n\n\nz\n2\n\n\n=\n\n3\n\n3\n\n+\n\ni\n\n and \n\n\nz\n3\n\n\n=\n\n8\n\ni\n\n     M1A1

\n

 

\n

Note:     Award M1 for subtracting 2i from their three roots.

\n

 

\n

METHOD 2

\n

\n\n\n\n(\n\na\n\n3\n\n+\n(\nb\n+\n2\n)\n\ni\n\n\n)\n\n3\n\n\n=\n216\n\ni\n\n

\n

\n\n\n\n(\n\na\n\n3\n\n\n)\n\n3\n\n\n+\n3\n\n\n\n(\n\na\n\n3\n\n\n)\n\n2\n\n\n(\nb\n+\n2\n)\n\ni\n\n\n3\n\n(\n\na\n\n3\n\n\n)\n\n\n(\nb\n+\n2\n\n)\n2\n\n\n\n\ni\n\n\n(\nb\n+\n2\n\n)\n3\n\n\n=\n216\n\ni\n\n     M1A1

\n

\n\n\n\n(\n\na\n\n3\n\n\n)\n\n3\n\n\n\n3\n\n(\n\na\n\n3\n\n\n)\n\n\n(\nb\n+\n2\n\n)\n2\n\n\n+\n\ni\n\n\n(\n\n3\n\n\n\n\n(\n\na\n\n3\n\n\n)\n\n\n2\n\n\n(\nb\n+\n2\n)\n\n\n\n\n(\nb\n+\n2\n)\n\n3\n\n\n\n)\n\n=\n216\n\ni\n\n

\n

\n\n\n\n(\n\na\n\n3\n\n\n)\n\n3\n\n\n\n3\n\n(\n\na\n\n3\n\n\n)\n\n\n(\nb\n+\n2\n\n)\n2\n\n\n=\n0\n and \n3\n\n\n\n(\n\na\n\n3\n\n\n)\n\n2\n\n\n(\nb\n+\n2\n)\n\n\n(\nb\n+\n2\n\n)\n3\n\n\n=\n216\n     M1A1

\n

\na\n\n(\n\n\n\na\n2\n\n\n\n\n\n\n(\nb\n+\n2\n)\n\n2\n\n\n\n)\n\n=\n0\n and \n9\n\n\na\n2\n\n\n(\nb\n+\n2\n)\n\n\n(\nb\n+\n2\n\n)\n3\n\n\n=\n216\n

\n

\na\n=\n0\n or \n\n\na\n2\n\n\n=\n\n(\nb\n+\n2\n\n)\n2\n\n\n

\n

if \na\n=\n0\n,\n\n \n\n\n\n(\nb\n+\n2\n\n)\n3\n\n\n=\n216\n\nb\n+\n2\n=\n\n6\n

\n

\n\nb\n=\n\n8\n     A1

\n

\n(\na\n,\n\n \n\nb\n)\n=\n(\n0\n,\n\n \n\n\n8\n)\n

\n

if \n\n\na\n2\n\n\n=\n\n(\nb\n+\n2\n\n)\n2\n\n\n,\n\n \n\n9\n\n(\nb\n+\n2\n\n)\n2\n\n\n(\nb\n+\n2\n)\n\n\n(\nb\n+\n2\n\n)\n3\n\n\n=\n216\n

\n

\n8\n\n(\nb\n+\n2\n\n)\n3\n\n\n=\n216\n

\n

\n\n(\nb\n+\n2\n\n)\n3\n\n\n=\n27\n

\n

\nb\n+\n2\n=\n3\n

\n

\nb\n=\n1\n

\n

\n\n\n\na\n2\n\n\n=\n9\n\na\n=\n±\n3\n

\n

\n\n(\na\n,\n\n \n\nb\n)\n=\n(\n±\n3\n,\n\n \n\n1\n)\n     A1A1

\n

so roots are \n\n\nz\n1\n\n\n=\n3\n\n3\n\n+\n\ni, \n\n\n\nz\n2\n\n\n=\n\n3\n\n3\n\n+\n\ni\n\n and \n\n\nz\n3\n\n\n=\n\n8\n\ni\n\n

\n

 

\n

METHOD 3

\n

\n\n(\nz\n+\n2\n\ni\n\n\n)\n3\n\n\n\n\n(\n\n6\n\ni\n\n\n)\n3\n\n\n=\n0\n

\n

attempt to factorise:     M1

\n

\n\n(\n\n(\nz\n+\n2\n\ni\n\n)\n\n(\n\n6\n\ni\n\n)\n\n)\n\n\n(\n\n\n\n\n(\nz\n+\n2\n\ni\n\n)\n\n2\n\n\n+\n(\nz\n+\n2\n\ni\n\n)\n(\n\n6\n\ni\n\n)\n+\n\n\n\n(\n\n6\n\ni\n\n)\n\n2\n\n\n\n)\n\n=\n0\n     A1

\n

\n(\nz\n+\n8\n\ni\n\n)\n(\n\n\nz\n2\n\n\n\n2\n\ni\n\nz\n\n28\n)\n=\n0\n     A1

\n

\nz\n+\n8\n\ni\n\n=\n0\n\nz\n=\n\n8\n\ni\n\n     A1

\n

\n\n\nz\n2\n\n\n\n2\n\ni\n\nz\n\n28\n=\n0\n\nz\n=\n\n\n2\n\ni\n\n±\n\n\n4\n\n(\n4\n×\n1\n×\n\n28\n)\n\n\n2\n\n     M1

\n

\nz\n=\n\n\n2\n\ni\n\n±\n\n108\n\n\n2\n\n

\n

\nz\n=\n\n\n2\n\ni\n\n±\n6\n\n3\n\n\n2\n\n

\n

\nz\n=\n\ni\n\n±\n3\n\n3\n\n     A1A1

\n

 

\n

Special Case:

\n

Note:     If a candidate recognises that \n\n\n216\n\ni\n\n\n3\n\n=\n\n6\n\ni\n\n (anywhere seen), and makes no valid progress in finding three roots, award A1 only.

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.AHL.TZ0.H_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers" ] }, { "Question": "
\n

A function \nf\n is given by \nf\n(\nx\n)\n=\n(\n2\nx\n+\n2\n)\n(\n5\n\n\n\nx\n2\n\n\n)\n.

\n
\n

The graph of the function \ng\n(\nx\n)\n=\n\n\n5\nx\n\n\n+\n6\nx\n\n6\n intersects the graph of \nf\n.

\n
\n

Expand the expression for \nf\n(\nx\n)\n.

\n
[1]
\n
b.i.
\n
\n

Find \n\nf\n\n\n(\nx\n)\n.

\n
[3]
\n
b.ii.
\n
\n

Draw the graph of \nf\n for \n\n3\n\nx\n\n3\n and \n\n40\n\ny\n\n20\n. Use a scale of 2 cm to represent 1 unit on the \nx\n-axis and 1 cm to represent 5 units on the \ny\n-axis.

\n
[4]
\n
d.
\n
\n

Write down the coordinates of the point of intersection.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

\n10\nx\n\n2\n\n\nx\n3\n\n\n+\n10\n\n2\n\n\nx\n2\n\n\n     (A1)

\n

 

\n

Notes:     The expansion may be seen in part (b)(ii).

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

\n10\n\n6\n\n\nx\n2\n\n\n\n4\nx\n     (A1)(ft)(A1)(ft)(A1)(ft)

\n

 

\n

Notes:     Follow through from part (b)(i). Award (A1)(ft) for each correct term. Award at most (A1)(ft)(A1)(ft)(A0) if extra terms are seen.

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

\"N17/5/MATSD/SP2/ENG/TZ0/05.d/M\"     (A1)(A1)(ft)(A1)(ft)(A1)

\n

 

\n

Notes:     Award (A1) for correct scale; axes labelled and drawn with a ruler.

\n

Award (A1)(ft) for their correct \nx\n-intercepts in approximately correct location.

\n

Award (A1) for correct minimum and maximum points in approximately correct location.

\n

Award (A1) for a smooth continuous curve with approximate correct shape. The curve should be in the given domain.

\n

Follow through from part (a) for the \nx\n-intercepts.

\n

 

\n

[4 marks]

\n
d.
\n
\n

\n(\n1.49\n,\n\n \n\n13.9\n)\n\n \n\n\n(\n\n(\n1.48702\n\n,\n\n \n\n13.8714\n\n)\n\n)\n\n     (G1)(ft)(G1)(ft)

\n

 

\n

Notes:     Award (G1) for 1.49 and (G1) for 13.9 written as a coordinate pair. Award at most (G0)(G1) if parentheses are missing. Accept \nx\n=\n1.49\n and \ny\n=\n13.9\n. Follow through from part (b)(i).

\n

 

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "17N.2.SL.TZ0.T_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-2-increasing-and-decreasing-functions" ] }, { "Question": "
\n

Consider the geometric sequence \n\n\nu\n1\n\n\n=\n18\n,\n\n \n\n\n\nu\n2\n\n\n=\n9\n,\n\n \n\n\n\nu\n3\n\n\n=\n4.5\n,\n\n \n\n\n.

\n
\n

Write down the common ratio of the sequence.

\n
[1]
\n
a.
\n
\n

Find the value of \n\n\nu\n5\n\n\n.

\n
[2]
\n
b.
\n
\n

Find the smallest value of \nn\n for which \n\n\nu\nn\n\n\n is less than \n\n\n10\n\n\n3\n\n\n\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n1\n2\n\n\n \n\n(\n0.5\n)\n     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

\n18\n×\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n4\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for their correct substitution into the geometric sequence formula. Accept a list of their five correct terms.

\n

 

\n

\n1.125\n\n \n\n\n(\n\n1.13\n,\n\n \n\n\n9\n8\n\n\n)\n\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from their common ratio from part (a).

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n18\n×\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n\nn\n\n1\n\n\n\n<\n\n\n10\n\n\n3\n\n\n\n     (M1)(M1)

\n

 

\n

Notes:     Award (M1) for their correct substitution into the geometric sequence formula with a variable in the exponent, (M1) for comparing their expression with \n\n\n10\n\n\n3\n\n\n\n\n \n\n\n(\n\n\n1\n\n1000\n\n\n\n)\n\n.

\n

Accept an equation.

\n

 

\n

\nn\n=\n16\n     (A1)(ft)     (C3)

\n

 

\n

Note:     Follow through from their common ratio from part (a). “\nn\n” must be a positive integer for the (A1) to be awarded.

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n\n27\n\n\n\n\nx\n2\n\n\n\n\n\n16\nx\n,\n\n\n\nx\n\n0\n.

\n
\n

Sketch the graph of y = f (x), for −4 ≤ x ≤ 3 and −50 ≤ y ≤ 100.

\n
[4]
\n
a.
\n
\n

Use your graphic display calculator to find the equation of the tangent to the graph of y = f (x) at the point (–2, 38.75).

\n

Give your answer in the form y = mx + c.

\n
[2]
\n
b.iii.
\n
\n

Sketch the graph of the function g (x) = 10x + 40 on the same axes.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

(A1)(A1)(A1)(A1)

\n

 

\n

Note: Award (A1) for axis labels and some indication of scale; accept y or f(x).

\n

Use of graph paper is not required. If no scale is given, assume the given window for zero and minimum point.

\n

Award (A1) for smooth curve with correct general shape.

\n

Award (A1) for x-intercept closer to y-axis than to end of sketch.

\n

Award (A1) for correct local minimum with x-coordinate closer to y-axis than end of sketch and y-coordinate less than half way to top of sketch.

\n

Award at most (A1)(A0)(A1)(A1) if the sketch intersects the y-axis or if the sketch curves away from the y-axis as x approaches zero.

\n

 

\n

[4 marks]

\n
a.
\n
\n

y = −9.25x + 20.3  (y = −9.25x + 20.25)      (A1)(A1)

\n

Note: Award (A1) for −9.25x, award (A1) for +20.25, award a maximum of (A0)(A1) if answer is not an equation.

\n

 

\n

[2 marks]

\n
b.iii.
\n
\n

correct line, y = 10x + 40, seen on sketch     (A1)(A1)

\n

Note: Award (A1) for straight line with positive gradient, award (A1) for x-intercept and y-intercept in approximately the correct positions. Award at most (A0)(A1) if ruler not used. If the straight line is drawn on different axes to part (a), award at most (A0)(A1).

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.2.SL.TZ0.T_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-1-equations-of-straight-lines-parallel-and-perpendicular" ] }, { "Question": "
\n

Solve \n\n\nz\n2\n\n\n=\n4\n\n\n\ne\n\n\n\nπ\n2\n\n\ni\n\n\n\n\n, giving your answers in the form

\n
\n

\nr\n\n\n\ne\n\n\n\ni\n\nθ\n\n\n\n where \nr\n\nθ\n\n\nR\n\n\nr\n>\n0\n.

\n
[3]
\n
a.
\n
\n

\na\n+\n\ni\n\nb\n where \na\n, \nb\n\n\nR\n\n.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nz\n=\n2\n\n\n\ne\n\n\n\nπ\n4\n\n\ni\n\n\n\n\n\n\n(\n\n=\n2\n\n\n\ne\n\n\n0.785\n\ni\n\n\n\n\n\n)\n\n      A1

\n

Note: Accept all answers in the form \n2\n\n\n\ne\n\n\n\n(\n\n\nπ\n4\n\n+\n2\nπ\nn\n\n)\n\n\ni\n\n\n\n\n.

\n

\nz\n=\n2\n\n\n\ne\n\n\n\n\n5\nπ\n\n4\n\n\ni\n\n\n\n\n\n\n(\n\n=\n2\n\n\n\ne\n\n\n3.93\n\ni\n\n\n\n\n\n)\n\n  OR  \nz\n=\n2\n\n\n\ne\n\n\n\n\n\n3\nπ\n\n4\n\n\ni\n\n\n\n\n\n\n(\n\n=\n2\n\n\n\ne\n\n\n\n2.36\n\ni\n\n\n\n\n\n)\n\n       (M1)A1

\n

Note: Accept all answers in the form \n2\n\n\n\ne\n\n\n\n(\n\n\n\n\n3\nπ\n\n4\n\n+\n2\nπ\nn\n\n)\n\n\ni\n\n\n\n\n.

\n

Note: Award M1A0 for correct answers in the incorrect form, eg \n\n2\n\n\n\ne\n\n\n\nπ\n4\n\n\ni\n\n\n\n\n.

\n

[3 marks]

\n
a.
\n
\n

\nz\n=\n1.41\n+\n1.41\n\ni\n\n\nz\n=\n\n1.41\n\n1.41\n\ni\n\n       A1A1

\n

\n\n(\n\nz\n=\n\n2\n\n+\n\n2\n\n\ni\n\n,\n\n\nz\n=\n\n\n2\n\n\n\n2\n\n\ni\n\n\n)\n\n

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.AHL.TZ1.H_2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers" ] }, { "Question": "
\n

The manager of a folder factory recorded the number of folders produced by the factory (in thousands) and the production costs (in thousand Euros), for six consecutive months.

\n

\"M17/5/MATSD/SP2/ENG/TZ2/03\"

\n
\n

Every month the factory sells all the folders produced. Each folder is sold for 2.99 Euros.

\n
\n

Draw a scatter diagram for this data. Use a scale of 2 cm for 5000 folders on the horizontal axis and 2 cm for 10 000 Euros on the vertical axis.

\n
[4]
\n
a.
\n
\n

Write down, for this set of data the mean number of folders produced, \n\n\nx\n¯\n\n\n;

\n
[1]
\n
b.i.
\n
\n

Write down, for this set of data the mean production cost, \n\n\nC\n¯\n\n\n.

\n
[1]
\n
b.ii.
\n
\n

Label the point \n\nM\n\n(\n\n\nx\n¯\n\n\n,\n\n \n\n\n\nC\n¯\n\n\n)\n on the scatter diagram.

\n
[1]
\n
c.
\n
\n

Use your graphic display calculator to find the Pearson’s product–moment correlation coefficient, \nr\n.

\n
[2]
\n
d.
\n
\n

State a reason why the regression line \nC\n on \nx\n is appropriate to model the relationship between these variables.

\n
[1]
\n
e.
\n
\n

Use your graphic display calculator to find the equation of the regression line \nC\n on \nx\n.

\n
[2]
\n
f.
\n
\n

Draw the regression line \nC\n on \nx\n on the scatter diagram.

\n
[2]
\n
g.
\n
\n

Use the equation of the regression line to estimate the least number of folders that the factory needs to sell in a month to exceed its production cost for that month.

\n
[4]
\n
h.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"M17/5/MATSD/SP2/ENG/TZ2/03.a/M\"     (A4)

\n

 

\n

Notes:     Award (A1) for correct scales and labels. Award (A0) if axes are reversed and follow through for their points.

\n

Award (A3) for all six points correctly plotted, (A2) for four or five points correctly plotted, (A1) for two or three points correctly plotted.

\n

If graph paper has not been used, award at most (A1)(A0)(A0)(A0). If accuracy cannot be determined award (A0)(A0)(A0)(A0).

\n

 

\n

[4 marks]

\n
a.
\n
\n

\n(\n\n\nx\n¯\n\n\n=\n)\n\n \n\n21\n     (A1)(G1)

\n

[1 mark]

\n
b.i.
\n
\n

\n(\n\n\nC\n¯\n\n\n=\n)\n\n \n\n55\n     (A1)(G1)

\n

 

\n

Note:     Accept (i) 21000 and (ii) 55000 seen.

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

their mean point M labelled on diagram     (A1)(ft)(G1)

\n

 

\n

Note:     Follow through from part (b).

\n

Award (A1)(ft) if their part (b) is correct and their attempt at plotting \n(\n21\n,\n\n \n\n55\n)\n in part (a) is labelled M.

\n

If graph paper not used, award (A1) if \n(\n21\n,\n\n \n\n55\n)\n is labelled. If their answer from part (b) is incorrect and accuracy cannot be determined, award (A0).

\n

 

\n

[1 mark]

\n
c.
\n
\n

\n(\nr\n=\n)\n\n \n\n0.990\n\n \n\n(\n0.989568\n\n)\n     (G2)

\n

 

\n

Note:     Award (G2) for 0.99 seen. Award (G1) for 0.98 or 0.989. Do not accept 1.00.

\n

 

\n

[2 marks]

\n
d.
\n
\n

the correlation coefficient/r is (very) close to 1     (R1)(ft)

\n

OR

\n

the correlation is (very) strong     (R1)(ft)

\n

 

\n

Note:     Follow through from their answer to part (d).

\n

 

\n

OR

\n

the position of the data points on the scatter graphs suggests that the tendency is linear     (R1)(ft)

\n

 

\n

Note:     Follow through from their scatter graph in part (a).

\n

[1 mark]

\n
e.
\n
\n

\nC\n=\n1.94\nx\n+\n14.2\n\n \n\n(\nC\n=\n1.94097\n\nx\n+\n14.2395\n\n)\n     (G2)

\n

 

\n

Notes:     Award (G1) for \n1.94\nx\n, (G1) for 14.2.

\n

Award a maximum of (G0)(G1) if the answer is not an equation.

\n

Award (G0)(G1)(ft) if gradient and \nC\n-intercept are swapped in the equation.

\n

 

\n

[2 marks]

\n
f.
\n
\n

straight line through their \n\nM\n\n(\n21\n,\n\n \n\n55\n)\n     (A1)(ft)

\n

\nC\n-intercept of the line (or extension of line) passing through \n14.2\n\n \n\n(\n±\n1\n)\n     (A1)(ft)

\n

 

\n

Notes:     Follow through from part (f). In the event that the regression line is not straight (ruler not used), award (A0)(A1)(ft) if line passes through both their \n(\n21\n,\n\n \n\n55\n)\n and \n(\n0\n,\n\n \n\n14.2\n)\n, otherwise award (A0)(A0). The line must pass through the midpoint, not near this point. If it is not clear award (A0).

\n

If graph paper is not used, award at most (A1)(ft)(A0).

\n

 

\n

[2 marks]

\n
g.
\n
\n

\n2.99\nx\n=\n1.94097\n\nx\n+\n14.2395\n\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for \n2.99\nx\n seen and (M1) for equating to their equation of the regression line. Accept an inequality sign.

\n

Accept a correct graphical method involving their part (f) and \n2.99\nx\n.

\n

Accept \nC\n=\n2.99\nx\n drawn on their scatter graph.

\n

 

\n

\nx\n=\n13.5739\n\n (this step may be implied by their final answer)     (A1)(ft)(G2)

\n

\n13\n\n600\n\n \n\n(\n13\n\n574\n)\n     (A1)(ft)(G3)

\n

 

\n

Note:     Follow through from their answer to (f). Use of 3 sf gives an answer of \n13\n\n524\n.

\n

Award (G2) for \n\n13.5739\n\n\n or 13.524 or a value which rounds to 13500 seen without workings.

\n

Award the last (A1)(ft) for correct multiplication by 1000 and an answer satisfying revenue > their production cost.

\n

Accept 13.6 thousand (folders).

\n

 

\n

[4 marks]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
", "question_id": "17M.2.SL.TZ2.T_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The random variable \nX\n has probability density function \nf\n given by

\n

\nf\n\n(\nx\n)\n\n=\n\n{\n\n\n\n\n\nk\n\n(\n\nπ\n\n\narcsin\n\n\nx\n\n)\n\n\n\n\n\n0\n\nx\n\n1\n\n\n\n\n\n0\n\n\n\n\notherwise\n\n\n\n\n\n\n\n\n,\n\n\n\nwhere \n\nk\n\n is a positive constant\n\n\n.\n\n

\n
\n

Given that \ny\n=\n\n(\n\n\n\n\n\nx\n2\n\n\n\n2\n\n\n)\n\n\narcsin\n\n\nx\n\n\n(\n\n\n1\n4\n\n\n)\n\n\narcsin\n\n\nx\n+\n\n(\n\n\nx\n4\n\n\n)\n\n\n1\n\n\n\nx\n2\n\n\n\n, show that

\n
\n

State the mode of X .

\n
[1]
\n
a.
\n
\n

Find  arcsin x d x .

\n
[3]
\n
b.i.
\n
\n

Hence show that k = 2 2 + π .

\n
[3]
\n
b.ii.
\n
\n

d y d x = x arcsin x .

\n
[4]
\n
c.i.
\n
\n

E ( X ) = 3 π 4 ( π + 2 ) .

\n
[5]
\n
c.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

mode is 0    A1

\n

[1 mark]

\n
a.
\n
\n

attempt at integration by parts      (M1)

\n

d u d x = 1 1 x 2 , d v = d x

\n

= x arcsin x x d x 1 x 2     A1

\n

= x arcsin x + 1 x 2 ( + c )     A1

\n

[3 marks]

\n
b.i.
\n
\n

0 1 ( π arcsin x ) d x = [ π x x arcsin x 1 x 2 ] 0 1    A1

\n

= ( π π 2 0 ) ( 0 0 1 ) = π 2 + 1

\n

= π + 2 2     A1

\n

0 1 k ( π arcsin x ) d x = 1    (M1)

\n

Note: This line can be seen (or implied) anywhere.

\n

Note: Do not allow FT A marks from bi to bii.

\n

k ( π + 2 2 ) = 1

\n

k = 2 2 + π     AG

\n

[3 marks]

\n
b.ii.
\n
\n

attempt to use product rule to differentiate    M1

\n

d y d x = x arcsin x + x 2 2 1 x 2 1 4 1 x 2 x 2 4 1 x 2 + 1 x 2 4   A2

\n

Note: Award A2 for all terms correct, A1 for 4 correct terms.

\n

= x arcsin x + 2 x 2 4 1 x 2 1 4 1 x 2 x 2 4 1 x 2 + 1 x 2 4 1 x 2     A1

\n

Note: Award A1 for equivalent combination of correct terms over a common denominator.

\n

= x arcsin x     AG

\n

[4 marks]

\n
c.i.
\n
\n

E ( X ) = k 0 1 x ( π arcsin x ) d x     M1

\n

= k 0 1 ( π x x arcsin x ) d x

\n

= k [ π x 2 2 x 2 2 arcsin x + 1 4 arcsin x x 4 1 x 2 ] 0 1       A1A1

\n

Note: Award A1 for first term, A1 for next 3 terms.

\n

= k [ ( π 2 π 4 + π 8 ) ( 0 ) ]       A1

\n

= ( 2 2 + π ) 3 π 8       A1

\n

= 3 π 4 ( π + 2 )     AG

\n

[5 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "19M.1.AHL.TZ2.H_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "ahl-4-14-properties-of-discrete-and-continuous-random-variables" ] }, { "Question": "
\n

The probability distribution of a discrete random variable, \nX\n, is given by the following table, where \nN\n and \np\n are constants.

\n

\n
\n

Find the value of p .

\n
[2]
\n
a.
\n
\n

Given that E ( X ) = 10 , find the value of N .

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

p = 1 1 2 1 5 1 5        (M1)

\n

= 1 10        A1

\n

[2 marks]

\n
a.
\n
\n

attempt to find  E ( X )         (M1)

\n

1 2 + 1 + 2 + N 10 = 10        A1

\n

N = 65        A1

\n

Note: Do not allow FT in part (b) if their p is outside the range 0 < p < 1 .

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.1.AHL.TZ0.H_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Boxes of mixed fruit are on sale at a local supermarket.

\n

Box A contains 2 bananas, 3 kiwifruit and 4 melons, and costs $6.58.

\n

Box B contains 5 bananas, 2 kiwifruit and 8 melons and costs $12.32.

\n

Box C contains 5 bananas and 4 kiwifruit and costs $3.00.

\n

Find the cost of each type of fruit.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

let \nb\n be the cost of one banana, \nk\n the cost of one kiwifruit, and \nm\n the cost of one melon

\n

attempt to set up three linear equations     (M1)

\n

\n2\nb\n+\n3\nk\n+\n4\nm\n=\n658\n

\n

\n5\nb\n+\n2\nk\n+\n8\nm\n=\n1232\n

\n

\n5\nb\n+\n4\nk\n=\n300\n     (A1)

\n

attempt to solve three simultaneous equations     (M1)

\n

\nb\n=\n36\n,\n\n \n\nk\n=\n30\n,\n\n \n\nm\n=\n124\n

\n

banana costs ($)0.36, kiwifruit costs ($)0.30, melon costs ($)1.24     A1

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.2.AHL.TZ0.H_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-16-solution-of-systems-of-linear-equations" ] }, { "Question": "
\n

Consider the following system of equations where \na\n\n\nR\n\n.

\n

\n2\nx\n+\n4\ny\n\nz\n=\n10\n

\n

\nx\n+\n2\ny\n+\na\nz\n=\n5\n

\n

\n5\nx\n+\n12\ny\n=\n2\na\n.

\n
\n

Find the value of \na\n for which the system of equations does not have a unique solution.

\n
[2]
\n
a.
\n
\n

Find the solution of the system of equations when \na\n=\n2\n.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

an attempt at a valid method eg by inspection or row reduction       (M1)

\n

\n2\n×\n\n\nR\n2\n\n\n=\n\n\nR\n1\n\n\n\n2\na\n=\n\n1\n

\n

\n\na\n=\n\n\n1\n2\n\n      A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

using elimination or row reduction to eliminate one variable      (M1)

\n

correct pair of equations in 2 variables, such as

\n

\n\n\n\n\n\n\n\n5\nx\n+\n10\ny\n=\n25\n\n\n\n\n\n\n5\nx\n+\n12\ny\n=\n4\n\n\n\n\n\n}\n\n      A1

\n

Note: Award A1 for \nz\n = 0 and one other equation in two variables.

\n

 

\n

attempting to solve for these two variables      (M1)

\n

\nx\n=\n26\n\ny\n=\n\n10.5\n,  \nz\n=\n0\n      A1A1

\n

Note: Award A1A0 for only two correct values, and A0A0 for only one.

\n

Note: Award marks in part (b) for equivalent steps seen in part (a).

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.1.AHL.TZ0.H_4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-16-solution-of-systems-of-linear-equations" ] }, { "Question": "
\n

Consider \nf\n\n(\nx\n)\n\n=\n\n\n2\nx\n\n4\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n\n\n\n1\n<\nx\n<\n1\n.

\n
\n

For the graph of \ny\n=\nf\n\n(\nx\n)\n\n,

\n
\n

Find  f ( x ) .

\n
[2]
\n
a.i.
\n
\n

Show that, if  f ( x ) = 0 , then  x = 2 3 .

\n
[3]
\n
a.ii.
\n
\n

find the coordinates of the y -intercept.

\n
[1]
\n
b.i.
\n
\n

show that there are no x -intercepts.

\n
[2]
\n
b.ii.
\n
\n

sketch the graph, showing clearly any asymptotic behaviour.

\n
[2]
\n
b.iii.
\n
\n

Show that 3 x + 1 1 x 1 = 2 x 4 x 2 1 .

\n
[2]
\n
c.
\n
\n

The area enclosed by the graph of y = f ( x ) and the line y = 4 can be expressed as ln v . Find the value of v .

\n
[7]
\n
d.
\n
", "Markscheme": "
\n

attempt to use quotient rule (or equivalent)       (M1)

\n

f ( x ) = ( x 2 1 ) ( 2 ) ( 2 x 4 ) ( 2 x ) ( x 2 1 ) 2        A1

\n

= 2 x 2 + 8 x 2 ( x 2 1 ) 2

\n

[2 marks]

\n
a.i.
\n
\n

f ( x ) = 0

\n

simplifying numerator (may be seen in part (i))       (M1)

\n

x 2 4 x + 1 = 0  or equivalent quadratic equation       A1

\n

 

\n

EITHER

\n

use of quadratic formula

\n

x = 4 ± 12 2        A1

\n

 

\n

OR

\n

use of completing the square

\n

( x 2 ) 2 = 3        A1

\n

 

\n

THEN

\n

x = 2 3   (since  2 + 3  is outside the domain)       AG

\n

 

\n

Note: Do not condone verification that x = 2 3 f ( x ) = 0 .

\n

Do not award the final A1 as follow through from part (i).

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

(0, 4)       A1

\n

[1 mark]

\n
b.i.
\n
\n

2 x 4 = 0 x = 2       A1

\n

outside the domain       R1

\n

[2 marks]

\n
b.ii.
\n
\n

      A1A1

\n

award A1 for concave up curve over correct domain with one minimum point in the first quadrant
award A1 for approaching x = ± 1 asymptotically

\n

[2 marks]

\n
b.iii.
\n
\n

valid attempt to combine fractions (using common denominator)      M1

\n

3 ( x 1 ) ( x + 1 ) ( x + 1 ) ( x 1 )       A1

\n

= 3 x 3 x 1 x 2 1

\n

= 2 x 4 x 2 1       AG

\n

[2 marks]

\n
c.
\n
\n

f ( x ) = 4 2 x 4 = 4 x 2 4       M1

\n

       ( x = 0   or)   x = 1 2       A1

\n

 

\n

area under the curve is  0 1 2 f ( x ) d x       M1

\n

= 0 1 2 3 x + 1 1 x 1 d x

\n

Note: Ignore absence of, or incorrect limits up to this point.

\n

 

\n

= [ 3 ln | x + 1 | ln | x 1 | ] 0 1 2       A1

\n

= 3 ln 3 2 ln 1 2 ( 0 )

\n

= ln 27 4       A1

\n

area is  2 0 1 2 f ( x ) d x   or  0 1 2 4 d x 0 1 2 f ( x ) d x       M1

\n

= 2 ln 27 4

\n

= ln 4 e 2 27       A1

\n

( v = 4 e 2 27 )

\n

 

\n

[7 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19N.1.AHL.TZ0.H_10", "topics": [ "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "ahl-2-13-rational-functions", "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

The first three terms of a geometric sequence are \n\n\nu\n1\n\n\n=\n486\n,\n\n \n\n\n\nu\n2\n\n\n=\n162\n,\n\n \n\n\n\nu\n3\n\n\n=\n54\n.

\n
\n

Find the value of \nr\n, the common ratio of the sequence.

\n
[2]
\n
a.
\n
\n

Find the value of \nn\n for which \n\n\nu\nn\n\n\n=\n2\n.

\n
[2]
\n
b.
\n
\n

Find the sum of the first 30 terms of the sequence.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n162\n\n\n486\n\n\n\n\n\n\nOR\n\n\n\n\n\n\n54\n\n\n162\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for dividing any \n\n\nu\n\nn\n+\n1\n\n\n\n by \n\n\nu\nn\n\n\n.

\n

 

\n

\n=\n\n1\n3\n\n\n \n\n(\n0.333\n,\n\n \n\n0.333333\n\n)\n     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

\n486\n\n\n\n(\n\n\n1\n3\n\n\n)\n\n\nn\n\n1\n\n\n\n=\n2\n     (M1)

\n

 

\n

Note:     Award (M1) for their correct substitution into geometric sequence formula.

\n

 

\n

\nn\n=\n6\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from part (a).

\n

Award (A1)(A0) for \n\n\nu\n6\n\n\n=\n2\n or \n\n\nu\n6\n\n\n with or without working.

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n\n\nS\n\n30\n\n\n\n=\n\n\n486\n\n(\n\n1\n\n\n\n\n\n1\n3\n\n\n\n30\n\n\n\n\n)\n\n\n\n1\n\n\n1\n3\n\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into geometric series formula.

\n

 

\n

\n=\n729\n     (A1)(ft)     (C2)

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ1.T_10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

The diagram shows part of the graph of a function \ny\n=\nf\n(\nx\n)\n. The graph passes through point \n\nA\n\n(\n1\n,\n\n \n\n3\n)\n.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/13\"

\n
\n

The tangent to the graph of \ny\n=\nf\n(\nx\n)\n at A has equation \ny\n=\n\n2\nx\n+\n5\n. Let \nN\n be the normal to the graph of \ny\n=\nf\n(\nx\n)\n at A.

\n
\n

Write down the value of f ( 1 ) .

\n
[1]
\n
a.
\n
\n

Find the equation of N . Give your answer in the form a x + b y + d = 0 where a , b , d Z .

\n
[3]
\n
b.
\n
\n

Draw the line N on the diagram above.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

3     (A1)     (C1)

\n

 

\n

Notes:     Accept y = 3

\n

 

\n

[1 mark]

\n
a.
\n
\n

3 = 0.5 ( 1 ) + c OR y 3 = 0.5 ( x 1 )     (A1)(A1)

\n

 

\n

Note:     Award (A1) for correct gradient, (A1) for correct substitution of A ( 1 ,   3 ) in the equation of line.

\n

 

\n

x 2 y + 5 = 0 or any integer multiple     (A1)(ft)     (C3)

\n

 

\n

Note:     Award (A1)(ft) for their equation correctly rearranged in the indicated form.

\n

The candidate’s answer must be an equation for this mark.

\n

 

\n

[3 marks]

\n
b.
\n
\n

\"M17/5/MATSD/SP1/ENG/TZ2/13.c/M\"     (M1)(A1)(ft)     (C2)

\n

 

\n

Note:     Award M1) for a straight line, with positive gradient, passing through ( 1 ,   3 ) , (A1)(ft) for line (or extension of their line) passing approximately through 2.5 or their intercept with the y -axis.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_13", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Rosa joins a club to prepare to run a marathon. During the first training session Rosa runs a distance of 3000 metres. Each training session she increases the distance she runs by 400 metres.

\n
\n

A marathon is 42.195 kilometres.

\n

In the \nk\nth training session Rosa will run further than a marathon for the first time.

\n
\n

Carlos joins the club to lose weight. He runs 7500 metres during the first month. The distance he runs increases by 20% each month.

\n
\n

Write down the distance Rosa runs in the third training session;

\n
[1]
\n
a.i.
\n
\n

Write down the distance Rosa runs in the \nn\nth training session.

\n
[2]
\n
a.ii.
\n
\n

Find the value of \nk\n.

\n
[2]
\n
b.
\n
\n

Calculate the total distance, in kilometres, Rosa runs in the first 50 training sessions.

\n
[4]
\n
c.
\n
\n

Find the distance Carlos runs in the fifth month of training.

\n
[3]
\n
d.
\n
\n

Calculate the total distance Carlos runs in the first year.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

3800 m     (A1)

\n

[1 mark]

\n
a.i.
\n
\n

\n3000\n+\n(\nn\n\n1\n)\n400\n\n m\n\n\n\n\n\nOR\n\n\n\n\n2600\n+\n400\nn\n\n m\n\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substitution into arithmetic sequence formula, (A1) for correct substitution.

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

\n3000\n+\n(\nk\n\n1\n)\n400\n>\n42195\n     (M1)

\n

 

\n

Notes:     Award (M1) for their correct inequality. Accept \n3\n+\n(\nk\n\n1\n)\n0.4\n>\n42.195\n.

\n

Accept \n=\n OR \n\n. Award (M0) for \n3000\n+\n(\nk\n\n1\n)\n400\n>\n42.195\n.

\n

 

\n

\n(\nk\n=\n)\n\n \n\n99\n     (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from part (a)(ii), but only if \nk\n is a positive integer.

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n\n\n50\n\n2\n\n\n(\n\n2\n×\n3000\n+\n(\n50\n\n1\n)\n(\n400\n)\n\n)\n\n     (M1)(A1)(ft)

\n

 

\n

Note:     Award (M1) for substitution into sum of an arithmetic series formula, (A1)(ft) for correct substitution.

\n

 

\n

\n640\n\n000\n\n m\n\n     (A1)

\n

 

\n

Note:     Award (A1) for their \n640\n\n000\n seen.

\n

 

\n

\n=\n640\n\n km\n\n     (A1)(ft)(G3)

\n

 

\n

Note:     Award (A1)(ft) for correctly converting their answer in metres to km; this can be awarded independently from previous marks.

\n

 

\n

OR

\n

\n\n\n50\n\n2\n\n\n(\n\n2\n×\n3\n+\n(\n50\n\n1\n)\n(\n0.4\n)\n\n)\n\n     (M1)(A1)(ft)(A1)

\n

 

\n

Note:     Award (M1) for substitution into sum of an arithmetic series formula, (A1)(ft) for correct substitution, (A1) for correctly converting 3000 m and 400 m into km.

\n

 

\n

\n=\n640\n\n km\n\n     (A1)(G3)

\n

[4 marks]

\n
c.
\n
\n

\n7500\n×\n\n\n1.2\n\n5\n\n1\n\n\n\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substitution into geometric series formula, (A1) for correct substitutions.

\n

 

\n

\n=\n15\n\n600\n\n m \n\n(\n15\n\n552\n\n m\n\n)\n     (A1)(G3)

\n

OR

\n

\n7.5\n×\n\n\n1.2\n\n5\n\n1\n\n\n\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substitution into geometric series formula, (A1) for correct substitutions.

\n

 

\n

\n=\n15.6\n\n km\n\n     (A1)(G3)

\n

[3 marks]

\n
d.
\n
\n

\n\n\n7500\n(\n\n\n\n1.2\n\n\n12\n\n\n\n\n1\n)\n\n\n1.2\n\n1\n\n\n     (M1)(A1)

\n

 

\n

Notes:     Award (M1) for substitution into sum of a geometric series formula, (A1) for correct substitutions. Follow through from their ratio (\nr\n) in part (d). If \nr\n<\n1\n (distance does not increase) or the final answer is unrealistic (eg \nr\n=\n20\n), do not award the final (A1).

\n

 

\n

\n=\n297\n\n000\n\n m \n\n(\n296\n\n853\n\n\n m\n\n,\n\n \n\n297\n\n km\n\n)\n     (A1)(G2)

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "17N.2.SL.TZ0.T_2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Consider the functions \nf\n and \ng\n defined by \nf\n\n(\nx\n)\n\n=\n\nln\n\n\n|\nx\n|\n\n, \nx\n\n\nR\n\n \\ \n\n{\n0\n}\n\n, and \ng\n\n(\nx\n)\n\n=\n\nln\n\n\n|\n\nx\n+\nk\n\n|\n\n\nx\n\n\nR\n\n \\ \n\n{\n\n\nk\n\n}\n\n, where \nk\n\n\nR\n\n\nk\n>\n2\n.

\n
\n

The graphs of \nf\n and \ng\n intersect at the point P .

\n
\n

Describe the transformation by which f ( x ) is transformed to g ( x ) .

\n
[1]
\n
a.
\n
\n

State the range of g .

\n
[1]
\n
b.
\n
\n

Sketch the graphs of y = f ( x ) and y = g ( x ) on the same axes, clearly stating the points of intersection with any axes.

\n
[6]
\n
c.
\n
\n

Find the coordinates of P.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

translation k units to the left (or equivalent)     A1

\n

[1 mark]

\n
a.
\n
\n

range is  ( g ( x ) ) R      A1

\n

[1 mark]

\n
b.
\n
\n

\n

correct shape of y = f ( x )        A1

\n

their f ( x ) translated k units to left (possibly shown by x = k marked on x -axis)       A1

\n

asymptote included and marked as x = k        A1

\n

f ( x )  intersects x -axis at x = 1 , x = 1        A1

\n

g ( x )  intersects  x -axis at x = k 1 , x = k + 1        A1

\n

g ( x )  intersects  y -axis at  y = ln k        A1

\n

Note: Do not penalise candidates if their graphs “cross” as x ± .

\n

Note: Do not award FT marks from the candidate’s part (a) to part (c).

\n

[6 marks]

\n
c.
\n
\n

at P   ln ( x + k ) = ln ( x )

\n

attempt to solve  x + k = x  (or equivalent)       (M1)

\n

x = k 2 y = ln ( k 2 )   (or  y = ln | k 2 | )       A1

\n

P ( k 2 , ln k 2 )   (or P ( k 2 , ln | k 2 | ) )

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.1.AHL.TZ2.H_11", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-11-transformation-of-functions" ] }, { "Question": "
\n

Consider the function \nf\n(\nx\n)\n=\n2\n\n\nsin\n2\n\n\nx\n+\n7\nsin\n\n2\nx\n+\ntan\n\nx\n\n9\n,\n\n \n\n0\n\nx\n<\n\nπ\n2\n\n.

\n
\n

Let \nu\n=\ntan\n\nx\n.

\n
\n

Determine an expression for f ( x ) in terms of x .

\n
[2]
\n
a.i.
\n
\n

Sketch a graph of y = f ( x ) for 0 x < π 2 .

\n
[4]
\n
a.ii.
\n
\n

Find the x -coordinate(s) of the point(s) of inflexion of the graph of y = f ( x ) , labelling these clearly on the graph of y = f ( x ) .

\n
[2]
\n
a.iii.
\n
\n

Express sin x in terms of u.

\n
[2]
\n
b.i.
\n
\n

Express sin 2 x in terms of u .

\n
[3]
\n
b.ii.
\n
\n

Hence show that f ( x ) = 0 can be expressed as u 3 7 u 2 + 15 u 9 = 0 .

\n
[2]
\n
b.iii.
\n
\n

Solve the equation f ( x ) = 0 , giving your answers in the form arctan k where k Z .

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

f ( x ) = 4 sin x cos x + 14 cos 2 x + sec 2 x (or equivalent)     (M1)A1

\n

[2 marks]

\n
a.i.
\n
\n

\"N17/5/MATHL/HP2/ENG/TZ0/11.a.ii/M\"     A1A1A1A1

\n

 

\n

Note:     Award A1 for correct behaviour at x = 0 , A1 for correct domain and correct behaviour for x π 2 , A1 for two clear intersections with x -axis and minimum point, A1 for clear maximum point.

\n

 

\n

[4 marks]

\n
a.ii.
\n
\n

x = 0.0736     A1

\n

x = 1.13     A1

\n

[2 marks]

\n
a.iii.
\n
\n

attempt to write sin x in terms of u only     (M1)

\n

sin x = u 1 + u 2     A1

\n

[2 marks]

\n
b.i.
\n
\n

cos x = 1 1 + u 2     (A1)

\n

attempt to use sin 2 x = 2 sin x cos x   ( = 2 u 1 + u 2 1 1 + u 2 )     (M1)

\n

sin 2 x = 2 u 1 + u 2     A1

\n

[3 marks]

\n
b.ii.
\n
\n

2 sin 2 x + 7 sin 2 x + tan x 9 = 0

\n

2 u 2 1 + u 2 + 14 u 1 + u 2 + u 9   ( = 0 )     M1

\n

2 u 2 + 14 u + u ( 1 + u 2 ) 9 ( 1 + u 2 ) 1 + u 2 = 0 (or equivalent)     A1

\n

u 3 7 u 2 + 15 u 9 = 0     AG

\n

[2 marks]

\n
b.iii.
\n
\n

u = 1 or u = 3     (M1)

\n

x = arctan ( 1 )     A1

\n

x = arctan ( 3 )     A1

\n

 

\n

Note:     Only accept answers given the required form.

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.2.AHL.TZ0.H_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

A hydraulic hammer drives a metal post vertically into the ground by striking the top of the post. The distance that the post is driven into the ground, by the \nn\n\nth\n\n strike of the hammer, is \n\n\nd\nn\n\n\n.

\n

The distances \n\n\nd\n1\n\n\n,\n\n \n\n\n\nd\n2\n\n\n,\n\n \n\n\n\nd\n3\n\n\n\n \n\n\n,\n\n \n\n\n\nd\nn\n\n\n form a geometric sequence.

\n

The distance that the post is driven into the ground by the first strike of the hammer, \n\n\nd\n1\n\n\n, is 64 cm.

\n

The distance that the post is driven into the ground by the second strike of the hammer, \n\n\nd\n2\n\n\n, is 48 cm.

\n
\n

Find the value of the common ratio for this sequence.

\n
[2]
\n
a.
\n
\n

Find the distance that the post is driven into the ground by the eighth strike of the hammer.

\n
[2]
\n
b.
\n
\n

Find the total depth that the post has been driven into the ground after 10 strikes of the hammer.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n48\n=\n64\nr\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into geometric sequence formula.

\n

 

\n

\n=\n0.75\n\n(\n\n\n3\n4\n\n,\n\n \n\n\n\n48\n\n\n64\n\n\n\n)\n\n    (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

\n64\n×\n\n(\n0.75\n\n)\n7\n\n\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into geometric sequence formula or list of eight values using their \nr\n. Follow through from part (a), only if answer is positive.

\n

 

\n

\n=\n8.54\n\n \n\n(\n\ncm\n\n)\n\n \n\n(\n8.54296\n\n\n cm\n\n)\n     (A1)(ft)     (C2)

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n\ndepth\n\n=\n\n\n64\n\n(\n\n1\n\n\n\n\n(\n0.75\n)\n\n\n10\n\n\n\n\n)\n\n\n\n1\n\n0.75\n\n\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into geometric series formula. Follow through from part (a), only if answer is positive.

\n

 

\n

\n=\n242\n(\n\ncm\n\n)\n\n \n\n(\n241.583\n\n)\n    (A1)(ft)     (C2)

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.1.SL.TZ0.T_10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

Consider the function \nf\n(\nx\n)\n=\n\n\n\nx\n4\n\n\n+\na\n\n\nx\n2\n\n\n+\n5\n, where \na\n is a constant. Part of the graph of \ny\n=\nf\n(\nx\n)\n is shown below.

\n

\"M17/5/MATSD/SP2/ENG/TZ2/06\"

\n
\n

It is known that at the point where \nx\n=\n2\n the tangent to the graph of \ny\n=\nf\n(\nx\n)\n is horizontal.

\n
\n

There are two other points on the graph of \ny\n=\nf\n(\nx\n)\n at which the tangent is horizontal.

\n
\n

Write down the \ny\n-intercept of the graph.

\n
[1]
\n
a.
\n
\n

Find \n\nf\n\n\n(\nx\n)\n.

\n
[2]
\n
b.
\n
\n

Show that \na\n=\n8\n.

\n
[2]
\n
c.i.
\n
\n

Find \nf\n(\n2\n)\n.

\n
[2]
\n
c.ii.
\n
\n

Write down the \nx\n-coordinates of these two points;

\n
[2]
\n
d.i.
\n
\n

Write down the intervals where the gradient of the graph of \ny\n=\nf\n(\nx\n)\n is positive.

\n
[2]
\n
d.ii.
\n
\n

Write down the range of \nf\n(\nx\n)\n.

\n
[2]
\n
e.
\n
\n

Write down the number of possible solutions to the equation \nf\n(\nx\n)\n=\n5\n.

\n
[1]
\n
f.
\n
\n

The equation \nf\n(\nx\n)\n=\nm\n, where \nm\n\n\nR\n\n, has four solutions. Find the possible values of \nm\n.

\n
[2]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

5     (A1)

\n

 

\n

Note:     Accept an answer of \n(\n0\n,\n\n \n\n5\n)\n.

\n

 

\n

[1 mark]

\n
a.
\n
\n

\n\n(\n\n\nf\n\n\n(\nx\n)\n=\n\n)\n\n\n4\n\n\nx\n3\n\n\n+\n2\na\nx\n     (A1)(A1)

\n

 

\n

Note:     Award (A1) for \n\n4\n\n\nx\n3\n\n\n and (A1) for \n+\n2\na\nx\n. Award at most (A1)(A0) if extra terms are seen.

\n

 

\n

[2 marks]

\n
b.
\n
\n

\n\n4\n×\n\n\n2\n3\n\n\n+\n2\na\n×\n2\n=\n0\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for substitution of \nx\n=\n2\n into their derivative, (M1) for equating their derivative, written in terms of \na\n, to 0 leading to a correct answer (note, the 8 does not need to be seen).

\n

 

\n

\na\n=\n8\n     (AG)

\n

[2 marks]

\n
c.i.
\n
\n

\n\n(\n\nf\n(\n2\n)\n=\n\n)\n\n\n\n\n2\n4\n\n\n+\n8\n×\n\n\n2\n2\n\n\n+\n5\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution of \nx\n=\n2\n and  \na\n=\n8\n into the formula of the function.

\n

 

\n

21     (A1)(G2)

\n

[2 marks]

\n
c.ii.
\n
\n

\n(\nx\n=\n)\n\n \n\n\n2\n,\n\n \n\n(\nx\n=\n)\n\n 0\n\n     (A1)(A1)

\n

 

\n

Note:     Award (A1) for each correct solution. Award at most (A0)(A1)(ft) if answers are given as \n(\n\n2\n\n \n\n,\n21\n)\n and \n(\n0\n,\n\n \n\n5\n)\n or \n(\n\n2\n,\n\n \n\n0\n)\n and \n(\n0\n,\n\n \n\n0\n)\n.

\n

 

\n

[2 marks]

\n
d.i.
\n
\n

\nx\n<\n\n2\n,\n\n \n\n0\n<\nx\n<\n2\n     (A1)(ft)(A1)(ft)

\n

 

\n

Note:     Award (A1)(ft) for \nx\n<\n\n2\n, follow through from part (d)(i) provided their value is negative.

\n

Award (A1)(ft) for \n0\n<\nx\n<\n2\n, follow through only from their 0 from part (d)(i); 2 must be the upper limit.

\n

Accept interval notation.

\n

 

\n

[2 marks]

\n
d.ii.
\n
\n

\ny\n\n21\n     (A1)(ft)(A1)

\n

 

\n

Notes:     Award (A1)(ft) for 21 seen in an interval or an inequality, (A1) for “\ny\n\n”.

\n

Accept interval notation.

\n

Accept \n\n\n<\ny\n\n21\n or \nf\n(\nx\n)\n\n21\n.

\n

Follow through from their answer to part (c)(ii). Award at most (A1)(ft)(A0) if \nx\n is seen instead of \ny\n. Do not award the second (A1) if a (finite) lower limit is seen.

\n

 

\n

[2 marks]

\n
e.
\n
\n

3 (solutions)     (A1)

\n

[1 mark]

\n
f.
\n
\n

\n5\n<\nm\n<\n21\n or equivalent     (A1)(ft)(A1)

\n

 

\n

Note:     Award (A1)(ft) for 5 and 21 seen in an interval or an inequality, (A1) for correct strict inequalities. Follow through from their answers to parts (a) and (c)(ii).

\n

Accept interval notation.

\n

 

\n

[2 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "17M.2.SL.TZ2.T_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

Juan buys a bicycle in a sale. He gets a discount of 30% off the original price and pays 560 US dollars (USD).

\n
\n

To buy the bicycle, Juan takes a loan of 560 USD for 6 months at a nominal annual interest rate of 75%, compounded monthly. Juan believes that the total amount he will pay will be less than the original price of the bicycle.

\n
\n

Calculate the original price of the bicycle.

\n
[2]
\n
a.
\n
\n

Calculate the difference between the original price of the bicycle and the total amount Juan will pay.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n560\n\n\n70\n\n\n×\n100\n (or equivalent)     (M1)

\n

 

\n

Note:     Award (M1) for dividing 560 by 0.7 or equivalent.

\n

 

\n

\n=\n800\n\n (USD)\n\n     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

\n560\n\n\n\n(\n\n1\n+\n\n\n75\n\n\n12\n×\n100\n\n\n\n)\n\n\n12\n×\n\n1\n2\n\n\n\n\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substitution into interest formula, (A1) for their correct substitution.

\n

 

\n

OR

\n

\n\nN\n\n=\n\n1\n2\n\n

\n

\n\nI% \n\n=\n75\n

\n

\n\nPV\n\n=\n(\n±\n)\n560\n

\n

\n\nP/Y\n\n=\n1\n

\n

\n\nC/Y\n\n=\n12\n     (A1)(M1)

\n

 

\n

Note:     Award (A1) for \n\nC/Y\n\n=\n12\n seen, (M1) for all other entries correct.

\n

OR

\n

\n\nN\n\n=\n6\n

\n

\n\nI% \n\n=\n75\n

\n

\n\nPV\n\n=\n(\n±\n)\n560\n

\n

\n\nP/Y\n\n=\n12\n

\n

\n\nC/Y\n\n=\n12\n     (A1)(M1)

\n

 

\n

Note:     Award (A1) for \n\nC/Y\n\n=\n12\n seen, (M1) for all other entries correct.

\n

 

\n

\n=\n805.678\n\n\n (USD)\n\n     (A1)

\n

 

\n

Note:     Award (A3) for 805.678… (806) seen without working.

\n

 

\n

(Juan spends) 5.68 (USD) (5.67828… USD) (more than the original price)     (A1)(ft)     (C4)

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.SL.TZ0.T_9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

Consider \nf\n(\nx\n)\n=\n\n1\n+\nln\n\n\n(\n\n\n\n\nx\n2\n\n\n\n1\n\n\n)\n\n

\n
\n

The function \nf\n is defined by \nf\n(\nx\n)\n=\n\n1\n+\nln\n\n\n(\n\n\n\n\nx\n2\n\n\n\n1\n\n\n)\n\n,\n\n \n\nx\n\nD\n

\n
\n

The function \ng\n is defined by \ng\n(\nx\n)\n=\n\n1\n+\nln\n\n\n(\n\n\n\n\nx\n2\n\n\n\n1\n\n\n)\n\n,\n\n \n\nx\n\n\n]\n\n1\n,\n\n \n\n\n\n[\n\n.

\n
\n

Find the largest possible domain \nD\n for \nf\n to be a function.

\n
[2]
\n
a.
\n
\n

Sketch the graph of \ny\n=\nf\n(\nx\n)\n showing clearly the equations of asymptotes and the coordinates of any intercepts with the axes.

\n
[3]
\n
b.
\n
\n

Explain why \nf\n is an even function.

\n
[1]
\n
c.
\n
\n

Explain why the inverse function \n\n\nf\n\n\n1\n\n\n\n does not exist.

\n
[1]
\n
d.
\n
\n

Find the inverse function \n\n\ng\n\n\n1\n\n\n\n and state its domain.

\n
[4]
\n
e.
\n
\n

Find \n\ng\n\n\n(\nx\n)\n.

\n
[3]
\n
f.
\n
\n

Hence, show that there are no solutions to \n\ng\n\n\n(\nx\n)\n=\n0\n;

\n
[2]
\n
g.i.
\n
\n

Hence, show that there are no solutions to \n(\n\n\ng\n\n\n1\n\n\n\n\n)\n\n\n(\nx\n)\n=\n0\n.

\n
[2]
\n
g.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nx\n2\n\n\n\n1\n>\n0\n     (M1)

\n

\nx\n<\n\n1\n or \nx\n>\n1\n     A1

\n

[2 marks]

\n
a.
\n
\n

\"M17/5/MATHL/HP2/ENG/TZ1/12.b/M\"

\n

shape     A1

\n

\nx\n=\n1\n and \nx\n=\n\n1\n     A1

\n

\nx\n-intercepts     A1

\n

[3 marks]

\n
b.
\n
\n

EITHER

\n

\nf\n is symmetrical about the \ny\n-axis     R1

\n

OR

\n

\nf\n(\n\nx\n)\n=\nf\n(\nx\n)\n     R1

\n

[1 mark]

\n
c.
\n
\n

EITHER

\n

\nf\n is not one-to-one function     R1

\n

OR

\n

horizontal line cuts twice     R1

\n

 

\n

Note:     Accept any equivalent correct statement.

\n

 

\n

[1 mark]

\n
d.
\n
\n

\nx\n=\n\n1\n+\nln\n\n\n(\n\n\n\n\ny\n2\n\n\n\n1\n\n\n)\n\n     M1

\n

\n\n\n\ne\n\n\n2\nx\n+\n2\n\n\n\n=\n\n\ny\n2\n\n\n\n1\n     M1

\n

\n\n\ng\n\n\n1\n\n\n\n(\nx\n)\n=\n\n\n\n\ne\n\n\n2\nx\n+\n2\n\n\n\n+\n1\n\n,\n\n \n\nx\n\n\nR\n\n     A1A1

\n

[4 marks]

\n
e.
\n
\n

\n\ng\n\n\n(\nx\n)\n=\n\n1\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n×\n\n\n2\nx\n\n\n2\n\n\n\nx\n2\n\n\n\n1\n\n\n\n     M1A1

\n

\n\ng\n\n\n(\nx\n)\n=\n\nx\n\n\n\nx\n2\n\n\n\n1\n\n\n     A1

\n

[3 marks]

\n
f.
\n
\n

\n\ng\n\n\n(\nx\n)\n=\n\nx\n\n\n\nx\n2\n\n\n\n1\n\n\n=\n0\n\nx\n=\n0\n     M1

\n

which is not in the domain of \ng\n (hence no solutions to \n\ng\n\n\n(\nx\n)\n=\n0\n)     R1

\n

 

\n

[2 marks]

\n
g.i.
\n
\n

\n(\n\n\ng\n\n\n1\n\n\n\n\n)\n\n\n(\nx\n)\n=\n\n\n\n\n\ne\n\n\n2\nx\n+\n2\n\n\n\n\n\n\n\n\n\ne\n\n\n2\nx\n+\n2\n\n\n\n+\n1\n\n\n\n     M1

\n

as \n\n\n\ne\n\n\n2\nx\n+\n2\n\n\n\n>\n0\n\n(\n\n\ng\n\n\n1\n\n\n\n\n)\n\n\n(\nx\n)\n>\n0\n so no solutions to \n(\n\n\ng\n\n\n1\n\n\n\n\n)\n\n\n(\nx\n)\n=\n0\n     R1

\n

 

\n

Note:     Accept: equation \n\n\n\ne\n\n\n2\nx\n+\n2\n\n\n\n=\n0\n has no solutions.

\n

 

\n

[2 marks]

\n
g.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.i.
\n
\n[N/A]\n
g.ii.
\n
", "question_id": "17M.2.AHL.TZ1.H_12", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Points \n\nA\n\n(0 , 0 , 10) , \n\nB\n\n(0 , 10 , 0) , \n\nC\n\n(10 , 0 , 0) , \n\nV\n\n(\np\n , \np\n , \np\n) form the vertices of a tetrahedron.

\n
\n

Consider the case where the faces \n\nABV\n\n and \n\nACV\n\n are perpendicular.

\n
\n

The following diagram shows the graph of \nθ\n against \np\n. The maximum point is shown by \n\nX\n\n.

\n

\n
\n

Show that  AB × AV = 10 ( 10 2 p p p )  and find a similar expression for AC × AV .

\n
[3]
\n
a.i.
\n
\n

Hence, show that, if the angle between the faces  ABV and  ACV is  θ , then cos θ = p ( 3 p 20 ) 6 p 2 40 p + 100 .

\n
[5]
\n
a.ii.
\n
\n

Find the two possible coordinates of V .

\n
[3]
\n
b.i.
\n
\n

Comment on the positions of V in relation to the plane ABC .

\n
[1]
\n
b.ii.
\n
\n

At X , find the value of p and the value of θ .

\n
[3]
\n
c.i.
\n
\n

Find the equation of the horizontal asymptote of the graph.

\n
[2]
\n
c.ii.
\n
", "Markscheme": "
\n

AV = ( p p p 10 )       A1

\n

AB × AV = ( 0 10 10 ) × ( p p p 10 ) = ( 10 ( p 10 ) + 10 p 10 p 10 p )       A1

\n

= ( 20 p 100 10 p 10 p ) = 10 ( 10 2 p p p )       AG

\n

AC × AV = ( 10 0 10 ) × ( p p p 10 ) = ( 10 p 100 20 p 10 p ) ( = 10 ( p 10 2 p p ) )       A1

\n

 

\n

[3 marks]

\n
a.i.
\n
\n

attempt to find a scalar product        M1

\n

10 ( 10 2 p p p ) 10 ( p 10 2 p p ) = 100 ( 3 p 2 20 p )

\n

OR  ( 10 2 p p p ) ( p 10 2 p p ) = 3 p 2 20 p       A1

\n

attempt to find magnitude of either  AB × AV   or   AC × AV         M1

\n

| 10 ( 10 2 p p p ) | = | 10 ( p 10 2 p p ) | = 10 ( 10 2 p ) 2 + 2 p 2         A1

\n

100 ( 3 p 2 20 p ) = 100 ( ( 10 2 p ) 2 + 2 p 2 ) 2 cos θ

\n

cos θ = 3 p 2 20 p ( 10 2 p ) 2 + 2 p 2         A1

\n

Note: Award A1 for any intermediate step leading to the correct answer.

\n

= p ( 3 p 20 ) 6 p 2 40 p + 100       AG

\n

Note: Do not allow FT marks from part (a)(i).

\n

[8 marks]

\n
a.ii.
\n
\n

p ( 3 p 20 ) = 0 p = 0   or   p = 20 3         M1A1

\n

coordinates are (0, 0, 0) and  ( 20 3 20 3 20 3 )       A1

\n

Note: Do not allow column vectors for the final A mark.

\n

[3 marks]

\n
b.i.
\n
\n

two points are mirror images in the plane
or opposite sides of the plane
or equidistant from the plane
or the line connecting the two Vs is perpendicular to the plane       R1

\n

[1 mark]

\n
b.ii.
\n
\n

geometrical consideration or attempt to solve  1 = p ( 3 p 20 ) 6 p 2 40 p + 100        (M1)

\n

p = 10 3 θ = π   or   θ = 180        A1A1

\n

[3 marks]

\n
c.i.
\n
\n

p cos θ 1 2          M1

\n

hence the asymptote has equation θ = π 3         A1

\n

[2 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "19N.1.AHL.TZ0.H_11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-16-vector-product", "ahl-3-18-intersections-of-lines-&-planes" ] }, { "Question": "
\n

Consider the equation \n\n\nz\n4\n\n\n=\n\n4\n, where \nz\n\n\nC\n\n.

\n
\n

Solve the equation, giving the solutions in the form  a + i b , where  a b R .

\n
[5]
\n
a.
\n
\n

The solutions form the vertices of a polygon in the complex plane. Find the area of the polygon.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

| z | = 4 4 ( = 2 )        (A1)

\n

arg ( z 1 ) = π 4        (A1)

\n

first solution is  1 + i        A1

\n

valid attempt to find all roots (De Moivre or +/− their components)        (M1)

\n

other solutions are  1 + i 1 i 1 i        A1

\n

 

\n

METHOD 2

\n

z 4 = 4

\n

( a + i b ) 4 = 4

\n

attempt to expand and equate both reals and imaginaries.        (M1)

\n

a 4 + 4 a 3 b i 6 a 2 b 2 4 a b 3 i + b 4 = 4

\n

( a 4 6 a 4 + a 4 = 4 ) a = ± 1 and  ( 4 a 3 b 4 a b 3 = 0 ) a = ± b        (A1)

\n

first solution is  1 + i        A1

\n

valid attempt to find all roots (De Moivre or +/− their components)        (M1)

\n

other solutions are  1 + i 1 i 1 i        A1

\n

 

\n

[5 marks]

\n
a.
\n
\n

complete method to find area of ‘rectangle'        (M1)

\n

= 4       A1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.1.AHL.TZ0.H_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers", "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

Tommaso plans to compete in a regional bicycle race after he graduates, however he needs to buy a racing bicycle. He finds a bicycle that costs 1100 euro (EUR). Tommaso has 950 EUR and invests this money in an account that pays 5 % interest per year, compounded monthly.

\n
\n

The cost of the bicycle, \nC\n, can be modelled by \nC\n=\n20\nx\n+\n1100\n, where \nx\n is the number of years since Tommaso invested his money.

\n
\n

Determine the amount that he will have in his account after 3 years. Give your answer correct to two decimal places.

\n
[3]
\n
a.
\n
\n

Find the difference between the cost of the bicycle and the amount of money in Tommaso’s account after 3 years. Give your answer correct to two decimal places.

\n
[3]
\n
b.
\n
\n

After \nm\n complete months Tommaso will, for the first time, have enough money in his account to buy the bicycle.

\n

Find the value of \nm\n.

\n
[5]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n950\n×\n\n\n\n(\n\n1\n+\n\n5\n\n12\n×\n100\n\n\n\n)\n\n\n12\n×\n3\n\n\n\n    (M1)(A1)

\n

Note: Award (M1) for substitution in the compound interest formula: (A1) for correct substitution.

\n

OR

\n

N = 3
I% = 5
PV = 950
P/Y = 1
C/Y = 12    (A1)(M1)

\n

Note: Award (A1) for C/Y = 12 seen, (M1) for other correct entries.

\n

OR

\n

N = 36
I% = 5
PV = 950
P/Y = 12
C/Y = 12    (A1)(M1)

\n

Note: Award (A1) for C/Y = 12 seen, (M1) for other correct entries.

\n

1103.40 (EUR)    (A1)(G3)

\n

Note: Answer must be given to 2 decimal places.

\n

[3 marks]

\n
a.
\n
\n

(20 × 3 + 1100) − 1103.40    (M1)(M1)

\n

Note: Award (M1) for correct substitution into cost of bike function, (M1) for subtracting their answer to part (a). This subtraction may be implied by their final answer (follow through from their part (a) for this implied subtraction).

\n

55.60 (EUR)    (A1)(ft)(G3)

\n

Note: Follow through from part (a). The answer must be two decimal places.

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

\n950\n×\n\n\n\n(\n\n1\n+\n\n5\n\n12\n×\n100\n\n\n\n)\n\n\n12\nx\n\n\n\n=\n20\nx\n+\n1100\n     (M1)(M1)

\n

Note: Award (M1) for their correct substitution in the compound interest formula with a variable in the exponent; (M1) for comparing their expressions provided variables are the same (not an expression with \nx\n for years and another with \nx\n representing months). Award at most (M0)(M1)(A0)(M1)(A0) for substitution of an integer in both expressions and comparison of the results. Accept inequality.

\n

(\nx\n =) 4.52157… (years)    (A1)(ft)

\n

4.52157… × 12 (= 54.2588…)     (M1)

\n

Note: Award (M1) for multiplying their value for \nx\n by 12. This may be implied.

\n

\nm\n = 55 (months)    (A1)(ft)(G4)

\n

 

\n

METHOD 2

\n

\n950\n×\n\n\n\n(\n\n1\n+\n\n5\n\n12\n×\n100\n\n\n\n)\n\nm\n\n\n=\n20\n×\n\nm\n\n12\n\n\n+\n1100\n     (M1)(M1)(M1)

\n

Note: Award (M1) for their correct substitution in the compound interest formula with a variable in the exponent to solve; (M1) for comparing their expressions provided variables are the same; (M1) for converting years to months in these expressions. Award at most (M0)(M1)(A0)(M1)(A0) for substitution of an integer in both expressions and comparison of the results. Accept inequality.

\n

\nm\n = 54.2588… (months)    (A1)(ft)

\n

\nm\n = 55 (months)    (A1)(ft)(G4)

\n

 

\n

METHOD 3

\n

     (M1)(M1)

\n

Note: Award (M1) for each graph drawn.

\n

(\nx\n =) 4.52157… (years)    (A1)(ft)

\n

4.52157… × 12 (= 54.2588…)     (M1)

\n

Note: Award (M1) for multiplying their value for \nx\n by 12. This may be implied.

\n

      If the graphs drawn are in terms of months, leading to a value of 54.2588…, award (M1)(M1)(M1)(A1), consistent with METHOD 2.

\n

\nm\n = 55 (months)    (A1)(ft)(G4)

\n

Note: Follow through for a compound interest formula consistent with their part (a). The final (A1)(ft) can only be awarded for correct answer, or their correct answer following through from previous parts and only if value is rounded up. For example, do not award (M0)(M0)(A0)(M1)(A1)(ft) for an unsupported “5 years × 12 = 60” or similar.

\n

 

\n

[5 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.SL.TZ2.T_6", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

Consider the function  f ( x ) = x e 2 x , where  x R . The  n th  derivative of  f ( x ) is denoted by  f ( n ) ( x ) .

\n

 

\n

Prove, by mathematical induction, that  f ( n ) ( x ) = ( 2 n x + n 2 n 1 ) e 2 x n Z + .

\n
", "Markscheme": "
\n

f ( x ) = e 2 x + 2 x e 2 x       A1

\n

Note: This must be obtained from the candidate differentiating  f ( x ) .

\n

= ( 2 1 x + 1 × 2 1 1 ) e 2 x       A1

\n

(hence true for n = 1 )

\n

 

\n

assume true for  n = k :      M1

\n

f ( k ) ( x ) = ( 2 k x + k 2 k 1 ) e 2 x

\n

Note: Award M1 if truth is assumed. Do not allow “let n = k ”.

\n

consider  n = k + 1 :

\n

f ( k + 1 ) ( x ) = d d x ( ( 2 k x + k 2 k 1 ) e 2 x )

\n

attempt to differentiate  f ( k ) ( x )        M1

\n

f ( k + 1 ) ( x ) = 2 k e 2 x + 2 ( 2 k x + k 2 k 1 ) e 2 x       A1

\n

f ( k + 1 ) ( x ) = ( 2 k + 2 k + 1 x + k 2 k ) e 2 x

\n

f ( k + 1 ) ( x ) = ( 2 k + 1 x + ( k + 1 ) 2 k ) e 2 x       A1

\n

     = ( 2 k + 1 x + ( k + 1 ) 2 ( k + 1 ) 1 ) e 2 x

\n

True for n = 1 and n = k true implies true for n = k + 1 .

\n

Therefore the statement is true for all  n ( Z + )       R1

\n

Note: Do not award final R1 if the two previous M1s are not awarded. Allow full marks for candidates who use the base case n = 0 .

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.1.AHL.TZ0.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

Write  2 x x 2 in the form  a ( x h ) 2 + k , where  a h k R .

\n
[2]
\n
a.
\n
\n

Hence, find the value of  1 2 3 2 1 2 x x 2 d x .

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

attempt to complete the square or multiplication and equating coefficients       (M1)

\n

2 x x 2 = ( x 1 ) 2 + 1       A1

\n

a = 1 h = 1 k = 1

\n

[2 marks]

\n
a.
\n
\n

use of their identity from part (a)  ( 1 2 3 2 1 1 ( x 1 ) 2 d x )         (M1)

\n

= [ arc sin ( x 1 ) ] 1 2 3 2 or  [ arc sin ( u ) ] 1 2 1 2        A1

\n

Note: Condone lack of, or incorrect limits up to this point.

\n

= arc sin ( 1 2 ) arc sin ( 1 2 )         (M1)

\n

= π 6 ( π 6 )        (A1)

\n

= π 3        A1

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.1.AHL.TZ0.H_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-15-further-derivatives-and-indefinite-integration-of-these-partial-fractions" ] }, { "Question": "
\n

The lengths of trout in a fisherman’s catch were recorded over one month, and are represented in the following histogram.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/01\"

\n
\n

Complete the following table.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/01\"

\n
[2]
\n
a.
\n
\n

State whether length of trout is a continuous or discrete variable.

\n
[1]
\n
b.
\n
\n

Write down the modal class.

\n
[1]
\n
c.
\n
\n

Any trout with length 40 cm or less is returned to the lake.

\n

Calculate the percentage of the fisherman’s catch that is returned to the lake.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"M17/5/MATSD/SP1/ENG/TZ1/01.a/M\"     (A2)     (C2)

\n

 

\n

Note:     Award (A2) for all correct entries, (A1) for 3 correct entries.

\n

 

\n

[2 marks]

\n
a.
\n
\n

continuous     (A1)     (C1)

\n

[1 mark]

\n
b.
\n
\n

\n\n60 (cm)\n\n<\n\ntrout length\n\n\n\n70 (cm)\n\n     (A1)     (C1)

\n

 

\n

Note:     Accept equivalent notation such as \n(\n60\n,\n\n \n\n70\n]\n or \n]\n60\n,\n\n \n\n70\n]\n.

\n

Award (A0) for “60-70” (incorrect notation).

\n

 

\n

[1 mark]

\n
c.
\n
\n

\n\n4\n\n22\n\n\n×\n100\n     (M1)

\n

 

\n

Note:     Award (M1) for their 4 divided by their 22.

\n

 

\n

\n=\n18.2\n\n \n\n(\n18.1818\n\n)\n     (A1)(ft)     (C2)

\n

 

\n

Note:     Follow through from their part (a). Do not accept 0.181818….

\n

 

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.1.SL.TZ1.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Given that 0 ln k e 2 x d x = 12 , find the value of k .

\n
", "Markscheme": "
\n

1 2 e 2 x seen       (A1)

\n

attempt at using limits in an integrated expression ( [ 1 2 e 2 x ] 0 ln k = 1 2 e 2 ln k 1 2 e 0 )         (M1)

\n

= 1 2 e ln k 2 1 2 e 0        (A1)

\n

Setting their equation  = 12        M1

\n

Note: their equation must be an integrated expression with limits substituted.

\n

1 2 k 2 1 2 = 12        A1

\n

( k 2 = 25 ) k = 5        A1

\n

Note: Do not award final A1 for  k = ± 5 .

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.1.AHL.TZ0.H_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

A straight line,  L θ , has vector equation r  = ( 5 0 0 ) + λ ( 5 sin θ cos θ ) λ θ R .

\n

The plane Πp, has equation x = p p R .

\n

Show that the angle between  L θ and Πp is independent of both  θ and  p .

\n
", "Markscheme": "
\n

a vector normal to Πp is  ( 1 0 0 )        (A1)

\n

Note: Allow any scalar multiple of  ( 1 0 0 ) , including  ( p 0 0 )

\n

attempt to find scalar product (or vector product) of direction vector of line with any scalar multiple of  ( 1 0 0 )         M1

\n

( 1 0 0 ) ( 5 sin θ cos θ ) = 5   (or  ( 1 0 0 ) × ( 5 sin θ cos θ ) = ( 0 cos θ sin θ ) )       A1

\n

(if  α  is the angle between the line and the normal to the plane)

\n

cos α = 5 1 × 25 + si n 2 θ + co s 2 θ (or  sin α = 1 1 × 25 + si n 2 θ + co s 2 θ )       A1

\n

cos α = 5 26 or  sin α = 1 26        A1

\n

this is independent of  p and  θ , hence the angle between the line and the plane,  ( 90 α ) , is also independent of  p and  θ        R1

\n

Note: The final R mark is independent, but is conditional on the candidate obtaining a value independent of p and  θ .

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.1.AHL.TZ0.H_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

The point A has coordinates (4 , −8) and the point B has coordinates (−2 , 4).

\n
\n

The point D has coordinates (−3 , 1).

\n
\n

Write down the coordinates of C, the midpoint of line segment AB.

\n
[2]
\n
a.
\n
\n

Find the gradient of the line DC.

\n
[2]
\n
b.
\n
\n

Find the equation of the line DC. Write your answer in the form ax + by + d = 0 where a , b and d are integers.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(1, −2)    (A1)(A1) (C2)
Note: Award (A1) for 1 and (A1) for −2, seen as a coordinate pair.

\n

Accept x = 1, y = −2. Award (A1)(A0) if x and y coordinates are reversed.

\n

[2 marks]

\n
a.
\n
\n

\n\n\n1\n\n\n(\n\n\n2\n\n)\n\n\n\n\n3\n\n1\n\n\n    (M1)

\n

Note: Award (M1) for correct substitution, of their part (a), into gradient formula.

\n

\n=\n\n\n3\n4\n\n\n\n\n\n(\n\n\n0.75\n\n)\n\n     (A1)(ft)  (C2)

\n

Note: Follow through from part (a).

\n

[2 marks]

\n

 

\n
b.
\n
\n

\ny\n\n1\n=\n\n\n3\n4\n\n\n(\n\nx\n+\n3\n\n)\n\n  OR  \ny\n+\n2\n=\n\n\n3\n4\n\n\n(\n\nx\n\n1\n\n)\n\n  OR  \ny\n=\n\n\n3\n4\n\nx\n\n\n5\n4\n\n      (M1)

\n

Note: Award (M1) for correct substitution of their part (b) and a given point.

\n

OR

\n

\n1\n=\n\n\n3\n4\n\n×\n\n3\n+\nc\n  OR  \n\n2\n=\n\n\n3\n4\n\n×\n1\n+\nc\n     (M1) 

\n

Note: Award (M1) for correct substitution of their part (b) and a given point.

\n

\n3\nx\n+\n4\ny\n+\n5\n=\n0\n  (accept any integer multiple, including negative multiples)    (A1)(ft) (C2)

\n

Note: Follow through from parts (a) and (b). Where the gradient in part (b) is found to be \n\n5\n0\n\n, award at most (M1)(A0) for either \nx\n=\n\n3\n or \nx\n+\n3\n=\n0\n.

\n

[2 marks]

\n

 

\n

 

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ1.T_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

In the following diagram, the points \n\nA\n\n\n\nB\n\n\n\nC\n\n and \n\nD\n\n are on the circumference of a circle with centre \n\nO\n\n and radius \nr\n\n\n[\n\n\nAC\n\n\n]\n\n is a diameter of the circle. \n\nBC\n\n=\nr\n\n\nAD\n\n=\n\nCD\n\n and \n\nA\n\n\n\nB\n\n\n\n\n\nC\n\n=\n\nA\n\n\n\nD\n\n\n\n\n\nC\n\n=\n\n90\n\n\n.

\n

\n
\n

Given that  cos 75 = q , show that  cos 105 = q .

\n
[1]
\n
a.
\n
\n

Show that B A D = 75 .

\n
[3]
\n
b.
\n
\n

By considering triangle  ABD , show that  B D 2 = 5 r 2 2 r 2 q 6 .

\n
[4]
\n
c.i.
\n
\n

By considering triangle CBD , find another expression for B D 2 in terms of r and q .

\n
[3]
\n
c.ii.
\n
\n

Use your answers to part (c) to show that  cos 75 = 1 6 + 2 .

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

cos 105 = cos ( 180 75 ) = cos 75       R1

\n

= q        AG

\n

Note: Accept arguments using the unit circle or graphical/diagrammatical considerations.

\n

[1 mark]

\n
a.
\n
\n

AD = CD C A D = 45       A1

\n

valid method to find  B A C         (M1)

\n

for example:  BC = r B C A = 60

\n

B A C = 30       A1

\n

hence  B A D = 45 + 30 = 75       AG

\n

[3 marks]

\n
b.
\n
\n

AB = r 3 AD = ( CD ) = r 2        A1A1

\n

applying cosine rule        (M1)

\n

B D 2 = ( r 3 ) 2 + ( r 2 ) 2 2 ( r 3 ) ( r 2 ) cos 75        A1

\n

= 3 r 2 + 2 r 2 2 r 2 6 cos 75

\n

=5r22r2q6       AG

\n

[4 marks]

\n
c.i.
\n
\n

B C D = 105         (A1)

\n

attempt to use cosine rule on  Δ BCD         (M1)

\n

B D 2 = r 2 + ( r 2 ) 2 2 r ( r 2 ) cos 105

\n

= 3 r 2 + 2 r 2 q 2        A1

\n

[3 marks]

\n
c.ii.
\n
\n

5 r 2 2 r 2 q 6 = 3 r 2 + 2 r 2 q 2         (M1)(A1)

\n

2 r 2 = 2 r 2 q ( 6 + 2 )        A1

\n

Note: Award A1 for any correct intermediate step seen using only two terms.

\n

q = 1 6 + 2        AG

\n

Note: Do not award the final A1 if follow through is being applied.

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "19N.1.AHL.TZ0.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Three planes have equations:

\n

2 x y + z = 5

\n

x + 3 y z = 4      , where  a b R .

\n

3 x 5 y + a z = b

\n

Find the set of values of a and b such that the three planes have no points of intersection.

\n
", "Markscheme": "
\n

attempt to eliminate a variable (or attempt to find det A )       M1

\n

( 2 1 1 1 3 1 3 5 a | 5 4 b ) ( 2 1 1 0 7 3 0 14 a + 3 | 5 3 b 12 )   (or det  A = 14 ( a 3 ) )

\n

(or two correct equations in two variables)       A1

\n

( 2 1 1 0 7 3 0 0 a 3 | 5 3 b 6 )   (or solving det  A = 0 )

\n

(or attempting to reduce to one variable, e.g.  ( a 3 ) z = b 6 )       M1

\n

a = 3 b 6        A1A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.1.AHL.TZ0.H_3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-16-solution-of-systems-of-linear-equations" ] }, { "Question": "
\n

The following diagram shows part of the graph of fx=kx, for x>0, k>0.

\n

Let Pp, kp be any point on the graph of f. Line L1 is the tangent to the graph of f at P.

\n

\n
\n

Line L1 intersects the x-axis at point A2p, 0 and the y-axis at point B.

\n
\n

Find f'p in terms of k and p.

\n
[2]
\n
a.i.
\n
\n

Show that the equation of L1 is kx+p2y-2pk=0.

\n
[2]
\n
a.ii.
\n
\n

Find the area of triangle AOB in terms of k.

\n
[5]
\n
b.
\n
\n

The graph of f is translated by 43 to give the graph of g.
In the following diagram:

\n\n

Line L2 is the tangent to the graph of g at Q, and passes through E and F.

\n

\n

Given that triangle EDF and rectangle CDFG have equal areas, find the gradient of L2 in terms of p.

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

f'x=-kx-2        (A1)

\n

f'p=-kp-2  =-kp2     A1     N2

\n

[2 marks]

\n
a.i.
\n
\n

attempt to use point and gradient to find equation of L1        M1

\n

eg    y-kp=-kp-2x-p,  kp=-kp2p+b

\n

correct working leading to answer        A1

\n

eg    p2y-kp=-kx+kp,  y-kp=-kp2x+kp,  y=-kp2x+2kp

\n

kx+p2y-2pk=0     AG     N0

\n

[2 marks]

\n
a.ii.
\n
\n

METHOD 1 – area of a triangle

\n

recognizing x=0 at B       (M1)

\n

correct working to find y-coordinate of null       (A1)

\n

eg   p2y-2pk=0

\n

y-coordinate of null at y=2kp (may be seen in area formula)        A1

\n

correct substitution to find area of triangle       (A1)

\n

eg   122p2kp,  p×2kp

\n

area of triangle AOB=2k     A1     N3

\n

 

\n

METHOD 2 – integration

\n

recognizing to integrate L1 between 0 and 2p       (M1)

\n

eg   02pL1dx , 02p-kp2x+2kp

\n

correct integration of both terms        A1

\n

eg   -kx22p2+2kxp , -k2p2x2+2kpx+c , -k2p2x2+2kpx02p

\n

substituting limits into their integrated function and subtracting (in either order)       (M1)

\n

eg    -k2p22p2+2k2pp-0, -4kp22p2+4kpp

\n

correct working       (A1)

\n

eg    -2k+4k

\n

area of triangle AOB=2k     A1     N3

\n

 

\n

[5 marks]

\n
b.
\n
\n

Note: In this question, the second M mark may be awarded independently of the other marks, so it is possible to award (M0)(A0)M1(A0)(A0)A0.

\n

 

\n

recognizing use of transformation      (M1)

\n

eg   area of triangle AOB = area of triangle DEFgx=kx-4+3, gradient of L2= gradient of L1, D4, 3, 2p+4,  one correct shift

\n

correct working       (A1)

\n

eg   area of triangle DEF=2k, CD=3, DF=2p, CG=2p, E4, 2kp+3, F2p+4, 3, Qp+4, kp+3, 

\n

gradient of L2=-kp2, g'x=-kx-42, area of rectangle CDFG=2k

\n

valid approach      (M1)

\n

eg   ED×DF2=CD×DF, 2p·3=2k , ED=2CD , 42p+4L2dx=4k

\n

correct working      (A1)

\n

eg   ED=6, E4, 9, k=3p, gradient=3-2kp+32p+4-4, -62k3, -9k

\n

correct expression for gradient (in terms of p)       (A1)

\n

eg   -62p, 9-34-2p+4, -3pp2, 3-23pp+32p+4-4, -93p

\n

gradient of L2 is -3p  =-3p-1     A1     N3

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

The following diagram shows a triangle ABC.

\n

\n

AC=15cm, BC=10cm, and AB^C=θ.

\n

Let sin CA^B=33.

\n
\n

Given that AB^C is acute, find sinθ.

\n
[3]
\n
a.
\n
\n

Find cos2×CA^B.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 – (sine rule)

\n

evidence of choosing sine rule       (M1)

\n

eg   sinA^a=sinB^b

\n

correct substitution       (A1)

\n

eg   3310=sinθ15 , 330=sinθ15 , 330=sinB15

\n

sinθ=32        A1  N2

\n

 

\n

METHOD 2 – (perpendicular from vertex C)

\n

valid approach to find perpendicular length (may be seen on diagram)       (M1)

\n

eg    h15=33

\n

correct perpendicular length       (A1)

\n

eg    1533 , 53

\n

sinθ=32        A1  N2

\n

 

\n

Note: Do not award the final A mark if candidate goes on to state sinθ=π3, as this demonstrates a lack of understanding.

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to substitute into double-angle formula for cosine       (M1)

\n

1-2332, 2632-1, 632-332, cos2θ=1-2322, 1-2sin233

\n

correct working       (A1)

\n

eg  1-2×39, 2×69-1, 69-39

\n

cos2×CA^B=39  =13          A1  N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.1.SL.TZ0.S_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Haruka has an eco-friendly bag in the shape of a cuboid with width 12 cm, length 36 cm and height of 9 cm. The bag is made from five rectangular pieces of cloth and is open at the top.

\n

 

\n

\n
\n

Nanako decides to make her own eco-friendly bag in the shape of a cuboid such that the surface area is minimized.

\n

The width of Nanako’s bag is x cm, its length is three times its width and its height is y cm.

\n

 

\n

\n

The volume of Nanako’s bag is 3888 cm3.

\n
\n

Calculate the area of cloth, in cm2, needed to make Haruka’s bag.

\n
[2]
\n
a.
\n
\n

Calculate the volume, in cm3, of the bag.

\n
[2]
\n
b.
\n
\n

Use this value to write down, and simplify, the equation in x and y for the volume of Nanako’s bag.

\n
[2]
\n
c.
\n
\n

Write down and simplify an expression in x and y for the area of cloth, A, used to make Nanako’s bag.

\n
[2]
\n
d.
\n
\n

Use your answers to parts (c) and (d) to show that

\n

\nA\n=\n3\n\n\nx\n2\n\n\n+\n\n\n10368\n\nx\n\n.

\n
[2]
\n
e.
\n
\n

Find \n\n\n\nd\n\nA\n\n\n\nd\n\nx\n\n\n.

\n
[3]
\n
f.
\n
\n

Use your answer to part (f) to show that the width of Nanako’s bag is 12 cm.

\n
[3]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

36 × 12 + 2(9 ×12) + 2(9 × 36)      (M1)

\n

Note: Award (M1) for correct substitution into surface area of cuboid formula.

\n

 

\n

= 1300 (cm2)  (1296 (cm2))       (A1)(G2)

\n

 

\n

[2 marks]

\n
a.
\n
\n

36 × 9 ×12     (M1)

\n

Note: Award (M1) for correct substitution into volume of cuboid formula.

\n

 

\n

= 3890 (cm3)  (3888 (cm3))       (A1)(G2)

\n

 

\n

[2 marks]

\n
b.
\n
\n

3\nx\n × \nx\n × \ny\n = 3888    (M1)

\n

Note: Award (M1) for correct substitution into volume of cuboid formula and equated to 3888.

\n

 

\n

\nx\n2\ny\n = 1296      (A1)(G2)

\n

Note: Award (A1) for correct fully simplified volume of cuboid.

\n

Accept \ny\n=\n\n\n1296\n\n\n\n\nx\n2\n\n\n\n\n.

\n

 

\n

[2 marks]

\n
c.
\n
\n

(A =) 3x2 + 2(xy) + 2(3xy)    (M1)

\n

Note: Award (M1) for correct substitution into surface area of cuboid formula.

\n

 

\n

(A =) 3x2 + 8xy       (A1)(G2)

\n

Note: Award (A1) for correct simplified surface area of cuboid formula.

\n

 

\n

 

\n

[2 marks]

\n
d.
\n
\n

\nA\n=\n3\n\n\nx\n2\n\n\n+\n8\nx\n\n(\n\n\n\n1296\n\n\n\n\nx\n2\n\n\n\n\n\n)\n\n     (A1)(ft)(M1)

\n

Note: Award (A1)(ft) for correct rearrangement of their part (c) seen (rearrangement may be seen in part(c)), award (M1) for substitution of their part (c) into their part (d) but only if this leads to the given answer, which must be shown.

\n

 

\n

\nA\n=\n3\n\n\nx\n2\n\n\n+\n\n\n10368\n\nx\n\n     (AG) 

\n

 

\n

[2 marks]

\n
e.
\n
\n

\n\n(\n\n\n\n\nd\n\nA\n\n\n\nd\n\nx\n\n\n\n)\n\n=\n6\nx\n\n\n\n10368\n\n\n\n\nx\n2\n\n\n\n\n      (A1)(A1)(A1)

\n

Note: Award (A1) for \n6\nx\n, (A1) for −10368, (A1) for \n\n\nx\n\n\n2\n\n\n\n. Award a maximum of (A1)(A1)(A0) if any extra terms seen.

\n

 

\n

[3 marks]

\n
f.
\n
\n

\n6\nx\n\n\n\n10368\n\n\n\n\nx\n2\n\n\n\n\n=\n0\n        (M1)

\n

Note: Award (M1) for equating their \n\n\n\n\nd\n\nA\n\n\n\nd\n\nx\n\n\n\n to zero.

\n

 

\n

\n6\n\n\nx\n3\n\n\n=\n10368\n  OR  \n6\n\n\nx\n3\n\n\n\n10368\n=\n0\n   OR   \n\n\nx\n3\n\n\n\n1728\n=\n0\n        (M1)

\n

Note: Award (M1) for correctly rearranging their equation so that fractions are removed.

\n

 

\n

\nx\n=\n\n\n1728\n\n3\n\n        (A1)

\n

\nx\n=\n12\n (cm)       (AG)

\n

Note: The (AG) line must be seen for the final (A1) to be awarded. Substituting \nx\n=\n12\n invalidates the method, award a maximum of (M1)(M0)(A0).

\n

 

\n

[3 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "18N.2.SL.TZ0.T_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus" ] }, { "Question": "
\n

Let fx=12-2x, xa. The following diagram shows part of the graph of f.

\n

The shaded region is enclosed by the graph of f, the x-axis and the y-axis.

\n

\n

The graph of f intersects the x-axis at the point a, 0.

\n
\n

Find the value of a.

\n
[2]
\n
a.
\n
\n

Find the volume of the solid formed when the shaded region is revolved 360° about the x-axis.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognize fx=0       (M1)

\n

eg   12-2x=0,  2x=12 

\n

a=6 (accept x=66, 0)    A1  N2

\n

[2 marks] 

\n
a.
\n
\n

attempt to substitute either their limits or the function into volume formula (must involve f2)      (M1)

\n

eg   06f2dx , π12-2x2 , π0612-2xdx 

\n

correct integration of each term      A1  A1

\n

eg   12x-x2 , 12x-x2+c , 12x-x206

\n

substituting limits into their integrated function and subtracting (in any order)      (M1)

\n

eg    π126-62-π0 , 72π-36π , 126-62-0

\n

 

\n

Note: Award M0 if candidate has substituted into f, f2 or f'.

\n

 

\n

volume=36π      A1  N2      

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.1.SL.TZ0.S_3", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-17-areas-under-curve-onto-y-axis-volume-of-revolution-(about-x-and-y-axes)" ] }, { "Question": "
\n

A and B  are acute angles such that  cos A = 2 3 and  sin B = 1 3 .

\n

Show that cos ( 2 A + B ) = 2 2 27 4 5 27 .

\n
", "Markscheme": "
\n

attempt to use  cos ( 2 A + B ) = cos 2 A cos B sin 2 A sin B (may be seen later)       M1

\n

attempt to use any double angle formulae (seen anywhere)       M1

\n

attempt to find either sin A or cos B (seen anywhere)       M1

\n

cos A = 2 3 sin A ( = 1 4 9 ) = 5 3        (A1)

\n

sin B = 1 3 cos B ( = 1 1 9 = 8 3 ) = 2 2 3        A1

\n

cos 2 A ( = 2 co s 2 A 1 ) = 1 9        A1

\n

sin 2 A ( = 2 sin A cos A ) = 4 5 9        A1

\n

So   cos ( 2 A + B ) = ( 1 9 ) ( 2 2 3 ) ( 4 5 9 ) ( 1 3 )

\n

= 2 2 27 4 5 27        AG

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19N.1.AHL.TZ0.H_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-10-compound-angle-identities" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\n\na\nx\n+\nb\n\n\nc\nx\n+\nd\n\n\n, for \nx\n\n\nR\n\n,\n\n\nx\n\n\n\nd\nc\n\n.

\n
\n

The function \ng\n is defined by \ng\n\n(\nx\n)\n\n=\n\n\n2\nx\n\n3\n\n\nx\n\n2\n\n\n,\n\n\nx\n\n\nR\n\n,\n\n\nx\n\n2\n

\n
\n

Express  g ( x ) in the form  A + B x 2  where A, B are constants.

\n
", "Markscheme": "
\n

g ( x ) = 2 + 1 x 2      A1A1

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ2.H_10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-6-simple-proof" ] }, { "Question": "
\n

Let fx=-x2+4x+5 and gx=-fx+k.

\n

Find the values of k so that gx=0 has no real roots.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 – (discriminant)

\n

correct expression for g      (A1)

\n

eg    --x2+4x+5+k , x2-4x-5+k=0

\n

evidence of discriminant      (M1)

\n

eg    b2-4ac, Δ

\n

correct substitution into discriminant of g      (A1)

\n

eg    -42-41-5+k , 16-4k-5

\n

recognizing discriminant is negative      (M1)

\n

eg    Δ<0 , -42-41-5+k<0 , 16<4k-5 , 16-4-15<0

\n

correct working (must be correct inequality)      (A1)

\n

eg    -4k<-36 , k-5>4 , 16+20-4k<0

\n

k>9        A1 N3

\n

 

\n

METHOD 2 – (transformation of vertex of f)

\n

valid approach for finding fx vertex      (M1)

\n

eg    -b2a=2 , f'x=0

\n

correct vertex of fx      (A1)

\n

eg    2, 9

\n

correct vertex of -fx      (A1)

\n

eg    2, -9

\n

correct vertex of gx      (A1)

\n

eg    2-9+0k , 2, -9+k

\n

recognizing when vertex is above x-axis      (M1)

\n

eg    -9+k>0, sketch

\n

k>9        A1 N3

\n

 

\n

METHOD 3 – (transformation of f)

\n

recognizing vertical reflection of fx      (M1)

\n

eg    -fx , x2-4x-5 , sketch

\n

correct expression for gx      (A1)

\n

eg    x2-4x-5+k

\n

valid approach for finding vertex of gx      (M1)

\n

eg    -b2a=2 , g'x=0

\n

correct y coordinate of vertex of gx      (A1)

\n

eg    y=-9+k , 2, -9+k

\n

recognizing when vertex is above x-axis      (M1)

\n

eg    -9+k>0 , sketch

\n

k>9        A1 N3

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.1.SL.TZ0.S_5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

Let fx=a log3x-4, for x>4, where a>0.

\n

Point A13, 7 lies on the graph of f.

\n
\n

Find the value of a.

\n
[3]
\n
a.
\n
\n

The x-intercept of the graph of f is 5, 0.

\n

On the following grid, sketch the graph of f.

\n

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to substitute coordinates (in any order) into f      (M1)

\n

eg    alog313-4=7 , alog37-4=13 , alog9=7

\n

finding log39=2 (seen anywhere)      (A1)

\n

eg    log39=2 , 2a=7

\n

a=72     A1  N2      

\n

[3 marks]

\n
a.
\n
\n

   A1A1A1  N3

\n

Note: Award A1 for correct shape of logarithmic function (must be increasing and concave down).
Only if the shape is correct, award the following:
A1 for being asymptotic to x=4
A1 for curve including both points in circles.  

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.1.SL.TZ0.S_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-9-exponential-and-logarithmic-functions" ] }, { "Question": "
\n

Each athlete on a running team recorded the distance (M miles) they ran in 30 minutes.

\n

The median distance is 4 miles and the interquartile range is 1.1 miles.

\n

This information is shown in the following box-and-whisker plot.

\n

\n
\n

The distance in miles, M, can be converted to the distance in kilometres, K, using the formula K=85M.

\n
\n

The variance of the distances run by the athletes is 169km2.

\n

The standard deviation of the distances is b miles.

\n
\n

A total of 600 athletes from different teams compete in a 5km race. The times the 600 athletes took to run the 5km race are shown in the following cumulative frequency graph.

\n

\n

There were 400 athletes who took between 22 and m minutes to complete the 5km race.

\n
\n

Find the value of a.

\n
[2]
\n
a.
\n
\n

Write down the value of the median distance in kilometres (km).

\n
[1]
\n
b.
\n
\n

Find the value of b.

\n
[4]
\n
c.
\n
\n

Find m.

\n
[3]
\n
d.
\n
\n

The first 150 athletes that completed the race won a prize.

\n

Given that an athlete took between 22 and m minutes to complete the 5km race, calculate the probability that they won a prize.

\n
[5]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)

\n

eg    Q3-Q1 , Q3-1.1 , 4.5-a=1.1

\n

a=3.4      A1   N2

\n

[2 marks]

\n
a.
\n
\n

325 =6.4 (km)       A1   N1

\n

[1 mark]

\n
b.
\n
\n

METHOD 1 (standard deviation first)

\n

valid approach        (M1)

\n

eg    standard deviation=variance , 169

\n

standard deviation=43 (km)       (A1)

\n

valid approach to convert their standard deviation        (M1)

\n

eg     43×58 , 169=85M

\n

2024 (miles)  =56      A1   N3

\n

 

\n

Note: If no working shown, award M1A1M0A0 for the value 43.
If working shown, and candidate’s final answer is 43, award M1A1M0A0.

\n

 

\n

METHOD 2 (variance first)

\n

valid approach to convert variance        (M1)

\n

eg   582 , 6425 , 169×582

\n

variance =2536       (A1)

\n

valid approach        (M1)

\n

eg    standard deviation=variance , 2536 , 169×582

\n

2024 (miles)  =56      A1   N3

\n

[4 marks]

\n
c.
\n
\n

correct frequency for 22 minutes       (A1)

\n

eg    20

\n

adding their frequency (do not accept 22+400)       (M1)

\n

eg    20+400 , 420 athletes

\n

m=30 (minutes)         A1   N3

\n

[3 marks]

\n
d.
\n
\n

27 (minutes)       (A1)

\n

correct working      (A1)

\n

eg    130 athletes between 22 and 27 minutes, P22<t<27=150-20600 , 1360

\n

evidence of conditional probability or reduced sample space      (M1)

\n

eg    PAB , Pt<2722<t<30 , P22<t<27P22<t<m , 150400

\n

correct working      (A1)

\n

eg    130600400600 , 150-20400

\n

130400 1340=78000240000=3901200=0.325      A1     N5

\n

 

\n

Note: If no other working is shown, award A0A0M1A0A0 for answer of 150400.
Award N0 for answer of 38 with no other working shown.

\n

 

\n

[5 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "20N.1.SL.TZ0.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

The fastest recorded speeds of eight animals are shown in the following table.

\n

\n
\n

State whether speed is a continuous or discrete variable.

\n
[1]
\n
a.
\n
\n

Write down the median speed for these animals.

\n
[1]
\n
b.
\n
\n

Write down the range of the animal speeds.

\n
[1]
\n
c.
\n
\n

For these eight animals find the mean speed.

\n
[2]
\n
d.i.
\n
\n

For these eight animals write down the standard deviation.

\n
[1]
\n
d.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

continuous    (A1) (C1)

\n

[1 mark]

\n
a.
\n
\n

75.5 (km h−1)   (A1) (C1)

\n

Note: Answer must be exact.

\n

[1 mark]

\n
b.
\n
\n

294 (km h−1)   (A1) (C1)

\n

[1 mark]

\n
c.
\n
\n

\n\n\n300\n+\n97\n+\n80\n+\n80\n+\n71\n+\n64\n+\n21\n+\n6\n\n8\n\n  OR  \n\n\n719\n\n8\n\n       (M1)

\n

Note: Award (M1) for correct sum divided by 8.

\n

89.9  (89.875)(km h−1)   (A1) (C2)

\n

[2 marks]

\n
d.i.
\n
\n

84.6  (84.5597…)(km h−1)   (A1) (C1)

\n

Note: If the response to part (d)(i) is awarded zero marks, a correct response to part (d)(ii) is awarded (C2).

\n

[1 mark]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "19M.1.SL.TZ1.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

The function \nf\n is defined by \nf\n\n(\nx\n)\n\n=\n\narcsin\n\n\n(\n\n2\nx\n\n)\n\n, where \n\n\n1\n2\n\n\nx\n\n\n1\n2\n\n.

\n
\n

By finding a suitable number of derivatives of f , find the first two non-zero terms in the Maclaurin series for f .

\n
[8]
\n
a.
\n
\n

Hence or otherwise, find lim x 0 arcsin ( 2 x ) 2 x ( 2 x ) 3 .

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

f ( x ) = arcsin ( 2 x )

\n

f ( x ) = 2 1 4 x 2        M1A1

\n

Note: Award M1A0 for  f ( x ) = 1 1 4 x 2

\n

f ( x ) = 8 x ( 1 4 x 2 ) 3 2         A1

\n

EITHER

\n

f ( x ) = 8 ( 1 4 x 2 ) 3 2 8 x ( 3 2 ( 8 x ) ( 1 4 x 2 ) 1 2 ) ( 1 4 x 2 ) 3 ( = 8 ( 1 4 x 2 ) 3 2 + 96 x 2 ( 1 4 x 2 ) 1 2 ( 1 4 x 2 ) 3 )         A1

\n

OR

\n

f ( x ) = 8 ( 1 4 x 2 ) 3 2 + 8 x ( 3 2 ( 1 4 x 2 ) 5 2 ) ( 8 x ) ( = 8 ( 1 4 x 2 ) 3 2 + 96 x 2 ( 1 4 x 2 ) 5 2 )         A1

\n

THEN

\n

substitute x = 0 into f or any of its derivatives         (M1)

\n

f ( 0 ) = 0 f ( 0 ) = 2 and  f ( 0 ) = 0         A1

\n

f ( 0 ) = 8

\n

the Maclaurin series is

\n

f ( x ) = 2 x + 8 x 3 6 + ( = 2 x + 4 x 3 3 + )          (M1)A1

\n

[8 marks]

\n
a.
\n
\n

METHOD 1

\n

lim x 0 arcsin ( 2 x ) 2 x ( 2 x ) 3 = lim x 0 2 x + 4 x 3 3 + 2 x 8 x 3        M1

\n

= lim x 0 4 3 +  terms with  x 8          (M1)

\n

= 1 6         A1

\n

Note: Condone the omission of +… in their working.

\n

 

\n

METHOD 2

\n

lim x 0 arcsin ( 2 x ) 2 x ( 2 x ) 3 = 0 0   indeterminate form, using L’Hôpital’s rule

\n

= lim x 0 2 1 4 x 2 2 24 x 2          M1

\n

= 0 0   indeterminate form, using L’Hôpital’s rule again

\n

= lim x 0 8 x ( 1 4 x 2 ) 3 2 48 x ( = lim x 0 1 6 ( 1 4 x 2 ) 3 2 )          M1

\n

Note: Award M1 only if their previous expression is in indeterminate form.

\n

= 1 6         A1

\n

Note: Award FT for use of their derivatives from part (a).

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19N.3.AHL.TZ0.HCA_3", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-19-maclaurin-series", "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Points A and B have coordinates 1, 1, 2 and 9, m, -6 respectively.

\n
\n

The line L, which passes through B, has equation r=-3-1924+s24-5.

\n
\n

Express AB in terms of m.

\n
[2]
\n
a.
\n
\n

Find the value of m.

\n
[5]
\n
b.
\n
\n

Consider a unit vector u, such that u=pi-23j+13k, where p>0.

\n

Point C is such that BC=9u.

\n

Find the coordinates of C.

\n
[8]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach to find AB        (M1)

\n

eg     OB-OA , A-B

\n

AB=8m-1-8       A1     N2

\n

[2 marks]

\n
a.
\n
\n

valid approach        (M1)

\n

eg     L=9m-6 , 9m-6=-3-1924+s24-5

\n

one correct equation        (A1)

\n

eg       -3+2s=9, -6=24-5s

\n

correct value for s            A1

\n

eg       s=6

\n

substituting their s value into their expression/equation to find m       (M1)

\n

eg       -19+6×4

\n

m=5       A1     N3

\n

[5 marks]

\n
b.
\n
\n

valid approach        (M1)

\n

eg     BC=9p-63, C=9u+B , BC=x-9y-5z+6

\n

correct working to find C        (A1)

\n

eg     OC=9p+9-1-3, C=9p-2313+95-6, y=-1 and z=-3

\n

correct approach to find u (seen anywhere)            A1

\n

eg     p2+-232+132 , p2+49+19

\n

recognizing unit vector has magnitude of 1        (M1)

\n

eg     u=1 , p2+-232+132=1 , p2+59=1

\n

correct working        (A1)

\n

eg     p2=49 , p=±23

\n

p=23            A1

\n

substituting their value of p        (M1)

\n

eg     x-9y-5z+6=6-63, C=6-63+95-6, C=923-2313+95-6, x-9=6

\n

C15, -1, -3  (accept 15-1-3)     A1     N4

\n

 

\n

Note: The marks for finding p are independent of the first two marks.
For example, it is possible to award marks such as (M0)(A0)A1(M1)(A1)A1 (M0)A0 or (M0)(A0)A1(M1)(A0)A0 (M1)A0.

\n

 

\n

[8 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.S_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

The graph of a function f passes through the point ln4, 20.

\n

Given that f'x=6e2x, find fx.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of integration      (M1)

\n

eg    f'xdx , 6e2x

\n

correct integration (accept missing +c)      (A1)

\n

eg    12×6e2x , 3e2x+c

\n

substituting initial condition into their integrated expression (must have +c)       M1

\n

eg    3e2×ln4+c=20

\n

 

\n

Note: Award M0 if candidate has substituted into f' or f''.

\n

 

\n

correct application of logab=bloga rule (seen anywhere)      (A1)

\n

eg    2ln4=ln16 , eln16 , ln42

\n

correct application of elna=a rule (seen anywhere)      (A1)

\n

eg    eln16=16 , eln42=42

\n

correct working      (A1)

\n

eg    3×16+c=20 , 3×42+c=20 , c=-28

\n

fx=3e2x-28        A1 N4

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.1.SL.TZ0.S_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

Consider a function fx, for x0. The derivative of f is given by f'x=6xx2+4.

\n
\n

The graph of f is concave-down when x>n.

\n
\n

Show that f''x=24-6x2x2+42.

\n
[4]
\n
a.
\n
\n

Find the least value of n.

\n
[2]
\n
b.
\n
\n

Find 6xx2+4dx.

\n
[3]
\n
c.
\n
\n

Let R be the region enclosed by the graph of f, the x-axis and the lines x=1 and x=3. The area of R is 19.6, correct to three significant figures.

\n

Find fx.

\n
[7]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

evidence of choosing the quotient rule        (M1)

\n

eg     vu'-uv'v2

\n

derivative of 6x is 6 (must be seen in rule)        (A1)

\n

derivative of x2+4 is 2x (must be seen in rule)        (A1)

\n

correct substitution into the quotient rule       A1

\n

eg     6x2+4-6x2xx2+42

\n

f''x=24-6x2x2+42       AG  N0

\n

 

\n

METHOD 2

\n

evidence of choosing the product rule        (M1)

\n

eg      vu'+uv'

\n

derivative of 6x is 6 (must be seen in rule)        (A1)

\n

derivative of x2+4-1 is -2xx2+4-2 (must be seen in rule)        (A1)

\n

correct substitution into the product rule       A1

\n

eg      6x2+4-1+-16x2xx2+4-2

\n

f''x=24-6x2x2+42       AG  N0

\n

 

\n

[4 marks]

\n
a.
\n
\n

METHOD 1 (2nd derivative)        (M1)

\n

valid approach

\n

eg     f''<0, 24-6x2<0 , n=±2, x=2

\n

n=2 (exact)       A1  N2

\n

 

\n

METHOD 2 (1st derivative)

\n

valid attempt to find local maximum on f'        (M1)

\n

eg     sketch with max indicated, 2, 1.5, x=2

\n

n=2 (exact)       A1  N2

\n

 

\n

[2 marks]

\n
b.
\n
\n

evidence of valid approach using substitution or inspection      (M1)

\n

eg     32x1udx , u=x2+4 , du=2xdx , 3×1udu

\n

6xx2+4dx=3lnx2+4+c      A2  N3

\n

[3 marks]

\n
c.
\n
\n

recognizing that area =13fxdx  (seen anywhere)      (M1)

\n

recognizing that their answer to (c) is their fx  (accept absence of c)      (M1)

\n

eg     fx=3lnx2+4+c , fx=3lnx2+4

\n

correct value for 133lnx2+4dx  (seen anywhere)      (A1)

\n

eg     12.4859

\n

correct integration for 13cdx  (seen anywhere)      (A1)

\n

cx13 , 2c

\n

adding their integrated expressions and equating to 19.6 (do not accept an expression which involves an integral)      (M1)

\n

eg     12.4859+2c=19.6 , 2c=7.114

\n

c=3.55700      (A1)

\n

fx=3lnx2+4+3.56       A1  N4

\n

[7 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "20N.2.SL.TZ0.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

In this question, all lengths are in metres and time is in seconds.

\n

Consider two particles, P1 and P2, which start to move at the same time.

\n

Particle P1 moves in a straight line such that its displacement from a fixed-point is given by st=10-74t2, for t0.

\n
\n

Find an expression for the velocity of P1 at time t.

\n
[2]
\n
a.
\n
\n

Particle P2 also moves in a straight line. The position of P2 is given by r=-16+t4-3.

\n

The speed of P1 is greater than the speed of P2 when t>q.

\n

Find the value of q.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognizing velocity is derivative of displacement     (M1)

\n

eg    v=dsdt , ddt10-74t2

\n

velocity=-144t   =-72t        A1 N2

\n

[2 marks]

\n
a.
\n
\n

valid approach to find speed of P2     (M1)

\n

eg    4-3 , 42+-32 , velocity=42+-32

\n

correct speed     (A1)

\n

eg   5m s-1

\n

recognizing relationship between speed and velocity (may be seen in inequality/equation)        R1

\n

eg   -72t , speed = | velocity | , graph of P1 speed ,  P1 speed =72t , P2 velocity =-5

\n

correct inequality or equation that compares speed or velocity (accept any variable for q)      A1

\n

eg   -72t>5 , -72q<-5 , 72q>5 , 72q=5

\n

q=107 (seconds) (accept t>107 , do not accept t=107)       A1   N2

\n

 

\n

Note: Do not award the last two A1 marks without the R1.

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.1.SL.TZ0.S_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

Consider the function fx=x2+x+50x, x0.

\n
\n

Find f1.

\n
[2]
\n
a.
\n
\n

Solve fx=0.

\n
[2]
\n
b.
\n
\n

The graph of f has a local minimum at point A.

\n

Find the coordinates of A.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to substitute x=1       (M1)

\n

eg       f1, 12+1+501

\n

52  (exact)       A1   N2

\n

[2 marks]

\n
a.
\n
\n

-4.04932

\n

-4.05       A2   N2

\n

[2 marks]

\n
b.
\n
\n

2.76649, 28.4934

\n

A2.77, 28.5       A1A1   N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.2.SL.TZ0.S_1", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

Lucy sells hot chocolate drinks at her snack bar and has noticed that she sells more hot chocolates on cooler days. On six different days, she records the maximum daily temperature, T, measured in degrees centigrade, and the number of hot chocolates sold, H. The results are shown in the following table.

\n

\n

The relationship between H and T can be modelled by the regression line with equation H=aT+b.

\n
\n

Find the value of a and of b.

\n
[3]
\n
a.i.
\n
\n

Write down the correlation coefficient.

\n
[1]
\n
a.ii.
\n
\n

Using the regression equation, estimate the number of hot chocolates that Lucy will sell on a day when the maximum temperature is 12°C.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid approach       (M1)

\n

eg    correct value for a or b (or for r or r2=0.962839 seen in (ii))

\n

a=-9.84636, b=221.592

\n

a=-9.85, b=222        A1A1   N3

\n

[3 marks]

\n
a.i.
\n
\n

-0.981244

\n

r=-0.981        A1  N1

\n

[1 mark]

\n
a.ii.
\n
\n

correct substitution into their equation       (A1)

\n

eg       -9.85×12+222

\n

103.435  (103.8 from 3 sf)

\n

103  (hot chocolates)        A1  N2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.2.SL.TZ0.S_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The equation of a curve is \ny\n=\n\n1\n2\n\n\n\nx\n4\n\n\n\n\n3\n2\n\n\n\nx\n2\n\n\n+\n7\n.

\n
\n

The gradient of the tangent to the curve at a point P is \n\n10\n.

\n
\n

Find \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n.

\n
[2]
\n
a.
\n
\n

Find the coordinates of P.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n2\n\n\nx\n3\n\n\n\n3\nx\n     (A1)(A1)     (C2)

\n

 

\n

Note:     Award (A1) for \n2\n\n\nx\n3\n\n\n, award (A1) for \n\n3\nx\n.

\n

Award at most (A1)(A0) if there are any extra terms.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n2\n\n\nx\n3\n\n\n\n3\nx\n=\n\n10\n    (M1)

\n

 

\n

Note:     Award (M1) for equating their answer to part (a) to \n\n10\n.

\n

 

\n

\nx\n=\n\n2\n    (A1)(ft)

\n

 

\n

Note:     Follow through from part (a). Award (M0)(A0) for \n\n2\n seen without working.

\n

 

\n

\ny\n=\n\n1\n2\n\n\n(\n\n2\n\n)\n4\n\n\n\n\n3\n2\n\n\n(\n\n2\n\n)\n2\n\n\n+\n7\n    (M1)

\n

 

\n

Note:     Award (M1) substituting their \n\n2\n into the original function.

\n

 

\n

\ny\n=\n9\n    (A1)(ft)     (C4)

\n

 

\n

Note:     Accept \n(\n\n2\n,\n\n \n\n9\n)\n.

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_14", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

A potter sells \nx\n vases per month.

\n

His monthly profit in Australian dollars (AUD) can be modelled by

\n

\nP\n\n(\nx\n)\n\n=\n\n\n1\n5\n\n\n\nx\n3\n\n\n+\n7\n\n\nx\n2\n\n\n\n120\n\n,\n\n\n\nx\n\n0.\n

\n
\n

Find the value of \nP\n if no vases are sold.

\n
[1]
\n
a.
\n
\n

Differentiate \nP\n\n(\nx\n)\n\n.

\n
[2]
\n
b.
\n
\n

Hence, find the number of vases that will maximize the profit.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

−120 (AUD)       (A1)   (C1)

\n

[1 mark]

\n
a.
\n
\n

\n\n\n3\n5\n\n\n\nx\n2\n\n\n+\n14\nx\n     (A1)(A1)     (C2)

\n

Note: Award (A1) for each correct term. Award at most (A1)(A0) for extra terms seen.

\n

[2 marks]

\n
b.
\n
\n

\n\n\n3\n5\n\n\n\nx\n2\n\n\n+\n14\nx\n=\n0\n     (M1)

\n

Note: Award (M1) for equating their derivative to zero.

\n

OR

\n

sketch of their derivative (approximately correct shape) with \nx\n-intercept seen       (M1)

\n

\n23\n\n1\n3\n\n\n\n\n\n(\n\n23.3\n\n,\n\n\n\n23.3333\n\n\n,\n\n\n\n\n\n70\n\n3\n\n\n)\n\n      (A1)(ft)

\n

Note: Award (C2) for \n23\n\n1\n3\n\n\n\n\n\n(\n\n23.3\n\n,\n\n\n\n23.3333\n\n\n,\n\n\n\n\n\n70\n\n3\n\n\n)\n\n seen without working.

\n

23      (A1)(ft)   (C3)     

\n

Note: Follow through from part (b).

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_15", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Let fx=4-x3 and gx=lnx, for x>0.

\n
\n

Find fgx.

\n
[2]
\n
a.
\n
\n

Solve the equation fgx=x.

\n
[2]
\n
b.i.
\n
\n

Hence or otherwise, given that g2a=f-12a, find the value of a.

\n
[3]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to form composite (in any order)       (M1)

\n

eg    flnx , g4-x3

\n

fgx=4-lnx3      A1  N2

\n

[2 marks]

\n
a.
\n
\n

valid approach using GDC      (M1)

\n

eg      , 2.85, 2.85

\n

2.85056

\n

2.85      A1  N2

\n

[2 marks]

\n
b.i.
\n
\n

METHOD 1 – (using properties of functions)

\n

recognizing inverse relationship       (M1)

\n

eg     fg2a=ff-12a  =2a

\n

equating 2a to their x from (i)       (A1)

\n

eg     2a=2.85056

\n

1.42528

\n

a=1.43       A1  N2

\n

 

\n

METHOD 2 – (finding inverse)

\n

interchanging x and y (seen anywhere)       (M1)

\n

eg     x=4-y3 , f-1x=4-x3

\n

correct working       (A1)

\n

eg     4-2a3=ln2a, sketch showing intersection of f-12x and g2x

\n

1.42528

\n

a=1.43       A1  N2

\n

 

\n

[3 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "20N.2.SL.TZ0.S_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

The following diagram shows a water wheel with centre O and radius 10 metres. Water flows into buckets, turning the wheel clockwise at a constant speed.

\n


The height, h metres, of the top of a bucket above the ground t seconds after it passes through point A is modelled by the function

\n

ht=13+8cosπ18t-6sinπ18t, for t0.

\n

\n
\n

A bucket moves around to point B which is at a height of 4.06 metres above the ground. It takes k seconds for the top of this bucket to go from point A to point B.

\n
\n

The chord [AB] is 17.0 metres, correct to three significant figures.

\n
\n

Find the height of point A above the ground.

\n
[2]
\n
a.i.
\n
\n

Calculate the number of seconds it takes for the water wheel to complete one rotation.

\n
[2]
\n
a.ii.
\n
\n

Hence find the number of rotations the water wheel makes in one hour.

\n
[2]
\n
a.iii.
\n
\n

Find k.

\n
[3]
\n
b.
\n
\n

Find AO^B.

\n
[3]
\n
c.
\n
\n

Determine the rate of change of h when the top of the bucket is at B.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

valid approach     (M1)

\n

eg      h0, 13+8cosπ18×0-6sinπ18×0, 13+8×1-6×0

\n

21 (metres)      A1   N2

\n

[2 marks]

\n
a.i.
\n
\n

valid approach to find the period (seen anywhere)    (M1)

\n

eg      36, 21, attempt to find two consecutive max/min, 50.3130-14.3130

\n

          2ππ18, b=2πperiod,

\n

36 (seconds) (exact)      A1   N2

\n

[2 marks]

\n
a.ii.
\n
\n

correct approach   (A1)

\n

eg      60×6036, 1.6666 rotations per minute

\n

100 (rotations)      A1   N2

\n

[2 marks]

\n
a.iii.
\n
\n

correct substitution into equation (accept the use of t)       (A1)

\n

eg      4.06=13+8cosπ18×k-6sinπ18×k

\n

valid attempt to solve their equation       (M1)

\n

eg      

\n

11.6510

\n

11.7      A1   N3

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

evidence of choosing the cosine rule or sine rule       (M1)

\n

eg      AB2=OA2+OB2-2×OA×OBcosAO^B, sinAO^BAB=sinOA^BOB

\n

correct working       (A1)

\n

eg      cosAO^B=102+102-17.022×10×10, -0.445, sinAO^B17.0=sinπ2-12AO^B10,

\n

         sinOA^B10=sinπ-2×OA^B17.0

\n

2.03197 , 116.423°

\n

2.03   116°      A1   N3

\n

 

\n

METHOD 2

\n

attempt to find the half central angle       (M1)

\n

eg      sin12AO^B=12ABOA

\n

correct working       (A1)

\n

eg      2×sin-18.510

\n

2.03197 , 116.423°

\n

2.03   116°      A1   N3

\n

 

\n

METHOD 3

\n

valid approach to find fraction of period       (M1)

\n

eg      k36, 11.651036

\n

correct approach to find angle       (A1)

\n

eg      k36×2π

\n

2.03348, 116.510°   (2.04203 using 11.7)

\n

2.03   117°      A1   N3

\n

 

\n

[3 marks]

\n
c.
\n
\n

recognizing rate of change is h'       (M1)

\n

eg      h'k, h'11.6510 , 0.782024

\n

-0.782024  (-0.768662 from 3 sf )

\n

rate of change is -0.782 ms-1    A1   N2

\n

(-0.769 ms-1 from 3 sf )

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "20N.2.SL.TZ0.S_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

The marks achieved by eight students in a class test are given in the following list.

\n

\n
\n

The teacher increases all the marks by 2. Write down the new value for

\n
\n

Find the mean.

\n
[1]
\n
a.i.
\n
\n

Find the standard deviation.

\n
[1]
\n
a.ii.
\n
\n

the mean.

\n
[1]
\n
b.i.
\n
\n

the standard deviation.

\n
[1]
\n
b.ii.
\n
\n

A ninth student also takes the test.

\n

Explain why the median is unchanged.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

6.75      A1

\n

[1 mark]

\n
a.i.
\n
\n

2.22      A1

\n

[1 mark]

\n
a.ii.
\n
\n

8.75      A1

\n

[1 mark]

\n
b.i.
\n
\n

2.22      A1

\n

[1 mark]

\n
b.ii.
\n
\n

the order is 3, 4, 6, 7, 7, 8, 9, 10

\n

median is currently 7        A1

\n

Note: This can be indicated by a diagram/list, rather than actually stated.

\n

with 9 numbers the middle value (median) will be the 5th value       R1

\n

which will correspond to 7 regardless of whether the position of the median moves up or down       R1

\n

Note: Accept answers using data 5, 6, 8, 9, 9, 10, 11, 12 (ie from part (b)).

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.AHL.TZ1.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

Consider the curve y = 5x3 − 3x.

\n
\n

The curve has a tangent at the point P(−1, −2).

\n
\n

Find the equation of this tangent. Give your answer in the form y = mx + c.

\n
", "Markscheme": "
\n

(y − (−2)) = 12 (x − (−1))     (M1)

\n

OR

\n

−2 = 12(−1) + c     (M1)

\n

Note: Award  (M1) for point and their gradient substituted into the equation of a line.

\n

 

\n

y = 12x + 10     (A1)(ft) (C2)

\n

Note: Follow through from part (b).

\n

 

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.1.SL.TZ0.T_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Consider the expansion of 3x2-kx9, where k>0.

\n

The coefficient of the term in x6 is 6048. Find the value of k.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach for expansion (must have correct substitution for parameters, but accept an incorrect value for r).       (M1)

\n

eg     9r3x29-r-kxr , 3x29+913x28-kx1+923x27-kx2+

\n

valid attempt to identify correct term       (M1)

\n

eg     29-r-r=6 , x2rx-19-r=x6

\n

identifying correct term (may be indicated in expansion)       (A1)

\n

eg     r=4, r=5

\n

correct term or coefficient in binominal expansion       (A1)

\n

eg     943x25-kx4 , 126243x10k4x4, 30618k4

\n

correct equation in k       (A1)

\n

eg     94243k4x6=6048x6 , 30618k4=6048

\n

k=23 (exact)  0.667       A1  N3 

\n

 

\n

Note: Do not award A1 if additional answers given.

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.2.SL.TZ0.S_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

A discrete random variable X has the following probability distribution.

\n

\n
\n

Find an expression for q in terms of p.

\n
[2]
\n
a.
\n
\n

Find the value of p which gives the largest value of EX.

\n
[3]
\n
b.i.
\n
\n

Hence, find the largest value of EX.

\n
[1]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of summing probabilities to 1       (M1)

\n

eg       q+4p2+p+0.7-4p2=1,  1-4p2-p-0.7+4p2

\n

q=0.3-p        A1  N2

\n

[2 marks]

\n
a.
\n
\n

correct substitution into EX formula       (A1)

\n

eg     0×0.3-p+1×4p2+2×p+3×0.7-4p2

\n

valid approach to find when EX is a maximum       (M1)

\n

eg     max on sketch of EX8p+2+3×-8p=0-b2a=-22×-8

\n

p=18 =0.125 (exact) (accept x=18)        A1  N3

\n

[3 marks]

\n
b.i.
\n
\n

2.225

\n

8940 (exact), 2.23      A1  N1

\n

[1 mark]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "20N.2.SL.TZ0.S_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Iqbal attempts three practice papers in mathematics. The probability that he passes the first paper is 0.6. Whenever he gains a pass in a paper, his confidence increases so that the probability of him passing the next paper increases by 0.1. Whenever he fails a paper the probability of him passing the next paper is 0.6.

\n
\n

Complete the given probability tree diagram for Iqbal’s three attempts, labelling each branch with the correct probability.

\n

\n
[3]
\n
a.
\n
\n

Calculate the probability that Iqbal passes at least two of the papers he attempts.

\n
[2]
\n
b.
\n
\n

Find the probability that Iqbal passes his third paper, given that he passed only one previous paper.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

     A1A1A1

\n

Note: Award A1 for each correct column of probabilities.

\n

[3 marks]

\n
a.
\n
\n

probability (at least twice) =

\n

EITHER

\n

( 0.6 × 0.7 × 0.8 ) + ( 0.6 × 0.7 × 0.2 ) + ( 0.6 × 0.3 × 0.6 ) + ( 0.4 × 0.6 × 0.7 )        (M1)

\n

OR

\n

( 0.6 × 0.7 ) + ( 0.6 × 0.3 × 0.6 ) + ( 0.4 × 0.6 × 0.7 )        (M1)

\n

Note: Award M1 for summing all required probabilities.

\n

THEN

\n

= 0.696     A1

\n

[2 marks]

\n
b.
\n
\n

P(passes third paper given only one paper passed before)

\n

= P ( passes third AND only one paper passed before ) P ( passes once in first two papers )       (M1)

\n

= ( 0.6 × 0.3 × 0.6 ) + ( 0.4 × 0.6 × 0.7 ) ( 0.6 × 0.3 ) + ( 0.4 × 0.6 )       A1

\n

= 0.657     A1

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.AHL.TZ2.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

An infinite geometric series has first term u1=a and second term u2=14a2-3a, where a>0.

\n
\n

Find the common ratio in terms of a.

\n
[2]
\n
a.
\n
\n

Find the values of a for which the sum to infinity of the series exists.

\n
[3]
\n
b.
\n
\n

Find the value of a when S=76.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of dividing terms (in any order)      (M1)

\n

eg       u1u2, 14a2-3aa

\n

r=14a-3      A1   N2

\n

[2 marks]

\n
a.
\n
\n

recognizing r<1 (must be in terms of a)      (M1)

\n

eg       14a-3<1,  -114a-31,  -4<a-12<4

\n

8<a<16      A2   N3

\n

[3 marks]

\n
b.
\n
\n

correct equation     (A1)

\n

eg       a1-14a-3=76, a=764-14a

\n

a=765 =15.2 (exact)      A2   N3

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.2.SL.TZ0.S_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-8-sum-of-infinite-geo-sequence" ] }, { "Question": "
\n

A quadratic function \nf\n is given by \nf\n(\nx\n)\n=\na\n\n\nx\n2\n\n\n+\nb\nx\n+\nc\n. The points \n(\n0\n,\n\n \n\n5\n)\n and \n(\n\n4\n,\n\n \n\n5\n)\n lie on the graph of \ny\n=\nf\n(\nx\n)\n.

\n
\n

The \ny\n-coordinate of the minimum of the graph is 3.

\n
\n

Find the equation of the axis of symmetry of the graph of \ny\n=\nf\n(\nx\n)\n.

\n
[2]
\n
a.
\n
\n

Write down the value of \nc\n.

\n
[1]
\n
b.
\n
\n

Find the value of \na\n and of \nb\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nx\n=\n\n2\n     (A1)(A1)     (C2)

\n

 

\n

Note:     Award (A1) for \nx\n=\n (a constant) and (A1) for \n\n2\n.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n(\nc\n=\n)\n\n \n\n5\n     (A1)     (C1)

\n

[1 mark]

\n
b.
\n
\n

\n\n\nb\n\n2\na\n\n\n=\n\n2\n

\n

\na\n\n(\n\n2\n\n)\n2\n\n\n\n2\nb\n+\n5\n=\n3\n or equivalent

\n

\na\n\n(\n\n4\n\n)\n2\n\n\n\n4\nb\n+\n5\n=\n5\n or equivalent

\n

\n2\na\n(\n\n2\n)\n+\nb\n=\n0\n or equivalent     (M1)

\n

 

\n

Note:     Award (M1) for two of the above equations.

\n

 

\n

\na\n=\n0.5\n     (A1)(ft)

\n

\nb\n=\n2\n     (A1)(ft)     (C3)

\n

 

\n

Note:     Award at most (M1)(A1)(ft)(A0) if the answers are reversed.

\n

Follow through from parts (a) and (b).

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.1.SL.TZ0.T_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Fiona walks from her house to a bus stop where she gets a bus to school. Her time, W minutes, to walk to the bus stop is normally distributed with W~N12, 32.

\n

Fiona always leaves her house at 07:15. The first bus that she can get departs at 07:30.

\n
\n

The length of time, B minutes, of the bus journey to Fiona’s school is normally distributed with B~N50, σ2. The probability that the bus journey takes less than 60 minutes is 0.941.

\n
\n

If Fiona misses the first bus, there is a second bus which departs at 07:45. She must arrive at school by 08:30 to be on time. Fiona will not arrive on time if she misses both buses. The variables W and B are independent.

\n
\n

Find the probability that it will take Fiona between 15 minutes and 30 minutes to walk to the bus stop.

\n
[2]
\n
a.
\n
\n

Find σ.

\n
[3]
\n
b.
\n
\n

Find the probability that the bus journey takes less than 45 minutes.

\n
[2]
\n
c.
\n
\n

Find the probability that Fiona will arrive on time.

\n
[5]
\n
d.
\n
\n

This year, Fiona will go to school on 183 days.

\n

Calculate the number of days Fiona is expected to arrive on time.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

0.158655

\n

P15<W<30=0.159    A2   N2

\n

[2 marks]

\n
a.
\n
\n

finding standardized value for 60       (A1)

\n

eg       z=1.56322

\n

correct substitution using their z-value       (A1)

\n

eg       60-50σ=1.56322, 60-501.56322=σ

\n

6.39703

\n

σ=6.40    A1   N3

\n

[3 marks]

\n
b.
\n
\n

0.217221

\n

PB<45=0.217    A2   N2

\n

[2 marks]

\n
c.
\n
\n

valid attempt to find one possible way of being on time (do not penalize incorrect use of strict inequality signs)       (M1)

\n

eg       W15 and B<6015<W30 and B<45

\n

correct calculation for PW15 and B<60 (seen anywhere)       (A1)

\n

eg       0.841×0.941, 0.7917

\n

correct calculation for P15<W30 and B<45 (seen anywhere)       (A1)

\n

eg       0.159×0.217, 0.03446

\n

correct working       (A1)

\n

eg       0.841×0.941+0.159×0.217, 0.7917+0.03446

\n

0.826168

\n

P (on time) =0.826    A1   N2

\n

[5 marks]

\n
d.
\n
\n

recognizing binomial with n=183, p=0.826168       (M1)

\n

eg       X~B183, 0.826

\n

151.188   (151.158 from 3 sf )

\n

151    A1   N2

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "20N.2.SL.TZ0.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

The following diagram shows a circle with centre O and radius 1cm. Points A and B lie on the circumference of the circle and AO^B=2θ, where 0<θ<π2.

\n

The tangents to the circle at A and B intersect at point C.

\n

\n

 

\n
\n

Show that AC=tanθ.

\n
[1]
\n
a.
\n
\n

Find the value of θ when the area of the shaded region is equal to the area of sector OADB.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct working for AC (seen anywhere)     A1

\n

eg       tanθ=ACOA, tanθ=AC1

\n

AC=tanθ      AG   N0

\n

[1 mark]

\n
a.
\n
\n

METHOD 1 (working with half the areas)

\n

area of triangle OAC or triangle OBC      (A1)

\n

eg      12×1×tanθ

\n

correct sector area      (A1)

\n

eg      12×θ×12 , 12θ

\n

correct approach using their areas to find the shaded area (seen anywhere)      (A1)

\n

eg      Atheir triangle-Atheir sector , 12θ-12tanθ

\n

correct equation      A1

\n

eg      12tanθ-12θ=12θ , tanθ=2θ

\n

1.16556

\n

1.17      A2   N4

\n

 

\n

METHOD 2 (working with entire kite and entire sector)

\n

area of kite OACB      (A1)

\n

eg      2×12×1×tanθ , 12×1cosθ×2sinθ

\n

correct sector area      (A1)

\n

eg      12×2θ×12 , θ

\n

correct approach using their areas to find the shaded area (seen anywhere)      (A1)

\n

eg      Akite OACB-Asector OADB , θ-tanθ

\n

correct equation      A1

\n

eg      tanθ-θ=θ , tanθ=2θ

\n

1.16556

\n

1.17      A2   N4

\n

 

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.2.SL.TZ0.S_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

Let \na\n=\n\nsin\n\n\nb\n,\n\n\n0\n<\nb\n<\n\nπ\n2\n\n.

\n

Find, in terms of b, the solutions of \n\nsin\n\n\n2\nx\n=\n\na\n,\n\n\n0\n\nx\n\nπ\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nsin\n\n\n2\nx\n=\n\n\nsin\n\n\nb\n

\n

EITHER

\n

\n\nsin\n\n\n2\nx\n=\n\nsin\n\n\n(\n\n\nb\n\n)\n\n or \n\nsin\n\n\n2\nx\n=\n\nsin\n\n\n(\n\nπ\n+\nb\n\n)\n\n or \n\nsin\n\n\n2\nx\n=\n\nsin\n\n\n(\n\n2\nπ\n\nb\n\n)\n\n …      (M1)(A1)

\n

Note: Award M1 for any one of the above, A1 for having final two.

\n

OR

\n

     (M1)(A1)

\n

Note: Award M1 for one of the angles shown with b clearly labelled, A1 for both angles shown. Do not award A1 if an angle is shown in the second quadrant and subsequent A1 marks not awarded.

\n

THEN

\n

\n2\nx\n=\nπ\n+\nb\n or \n2\nx\n=\n2\nπ\n\nb\n     (A1)(A1)

\n

\nx\n=\n\nπ\n2\n\n+\n\nb\n2\n\n,\n\n\nx\n=\nπ\n\n\nb\n2\n\n     A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ1.H_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-8-solving-trig-equations" ] }, { "Question": "
\n

On one day 180 flights arrived at a particular airport. The distance travelled and the arrival status for each incoming flight was recorded. The flight was then classified as on time, slightly delayed, or heavily delayed.

\n

The results are shown in the following table.

\n

\n

A χ2 test is carried out at the 10 % significance level to determine whether the arrival status of incoming flights is independent of the distance travelled.

\n
\n

The critical value for this test is 7.779.

\n
\n

A flight is chosen at random from the 180 recorded flights.

\n
\n

State the alternative hypothesis.

\n
[1]
\n
a.
\n
\n

Calculate the expected frequency of flights travelling at most 500 km and arriving slightly delayed.

\n
[2]
\n
b.
\n
\n

Write down the number of degrees of freedom.

\n
[1]
\n
c.
\n
\n

Write down the χ2 statistic.

\n
[2]
\n
d.i.
\n
\n

Write down the associated p-value.

\n
[1]
\n
d.ii.
\n
\n

State, with a reason, whether you would reject the null hypothesis.

\n
[2]
\n
e.
\n
\n

Write down the probability that this flight arrived on time.

\n
[2]
\n
f.
\n
\n

Given that this flight was not heavily delayed, find the probability that it travelled between 500 km and 5000 km.

\n
[2]
\n
g.
\n
\n

Two flights are chosen at random from those which were slightly delayed.

\n

Find the probability that each of these flights travelled at least 5000 km.

\n
[3]
\n
h.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

The arrival status is dependent on the distance travelled by the incoming flight     (A1)

\n

Note: Accept “associated” or “not independent”.

\n

[1 mark]

\n
a.
\n
\n

\n\n\n60\n×\n45\n\n\n180\n\n\n  OR  \n\n\n60\n\n\n180\n\n\n×\n\n\n45\n\n\n180\n\n\n×\n180\n     (M1)

\n

Note: Award (M1) for correct substitution into expected value formula.

\n

= 15     (A1) (G2)

\n

[2 marks]

\n
b.
\n
\n

4     (A1)

\n

Note: Award (A0) if “2 + 2 = 4” is seen.

\n

[1 mark]

\n
c.
\n
\n

9.55 (9.54671…)    (G2)

\n

Note: Award (G1) for an answer of 9.54.

\n

[2 marks]

\n
d.i.
\n
\n

0.0488 (0.0487961…)     (G1)

\n

[1 mark]

\n
d.ii.
\n
\n

Reject the Null Hypothesis     (A1)(ft)

\n

Note: Follow through from their hypothesis in part (a).

\n

9.55 (9.54671…) > 7.779     (R1)(ft)

\n

OR

\n

0.0488 (0.0487961…) < 0.1     (R1)(ft)

\n

Note: Do not award (A1)(ft)(R0)(ft). Follow through from part (d). Award (R1)(ft) for a correct comparison, (A1)(ft) for a consistent conclusion with the answers to parts (a) and (d). Award (R1)(ft) for χ2calc > χ2crit , provided the calculated value is explicitly seen in part (d)(i).

\n

[2 marks]

\n
e.
\n
\n

\n\n\n52\n\n\n180\n\n\n\n\n\n(\n\n0.289\n,\n\n\n\n\n13\n\n\n45\n\n\n,\n\n\n28.9\n\n\n\n\n\n)\n\n     (A1)(A1) (G2)

\n

Note: Award (A1) for correct numerator, (A1) for correct denominator.

\n

[2 marks]

\n
f.
\n
\n

\n\n\n35\n\n\n97\n\n\n\n\n\n(\n\n0.361\n,\n\n\n36.1\n\n\n\n\n\n)\n\n     (A1)(A1) (G2)

\n

Note: Award (A1) for correct numerator, (A1) for correct denominator.

\n

[2 marks]

\n
g.
\n
\n

\n\n\n14\n\n\n45\n\n\n×\n\n\n13\n\n\n44\n\n\n     (A1)(M1)

\n

Note: Award (A1) for two correct fractions and (M1) for multiplying their two fractions.

\n

\n=\n\n\n182\n\n\n1980\n\n\n\n\n\n(\n\n0.0919\n,\n\n\n\n\n91\n\n\n990\n\n\n,\n\n0.091919\n\n,\n\n9.19\n\n\n\n\n\n)\n\n     (A1) (G2)

\n

[3 marks]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
\n[N/A]\n
h.
\n
", "question_id": "18M.2.SL.TZ1.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

In triangle ABC, AB = 5, BC = 14 and AC = 11.

\n

Find all the interior angles of the triangle. Give your answers in degrees to one decimal place.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to apply cosine rule       M1

\n

cos A = 5 2 + 11 2 14 2 2 × 5 × 11 = 0.4545

\n

A = 117.03569

\n

A = 117.0         A1

\n

attempt to apply sine rule or cosine rule:       M1

\n

sin 117.03569 14 = sin B 11

\n

B = 44.4153

\n

B = 44.4         A1

\n

C = 180 A B

\n

C = 18.5         A1

\n

Note: Candidates may attempt to find angles in any order of their choosing.

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.2.AHL.TZ2.H_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

There are 75 players in a golf club who take part in a golf tournament. The scores obtained on the 18th hole are as shown in the following table.

\n

\"M17/5/MATHL/HP2/ENG/TZ2/01\"

\n
\n

One of the players is chosen at random. Find the probability that this player’s score was 5 or more.

\n
[2]
\n
a.
\n
\n

Calculate the mean score.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

P ( 5  or more ) = 29 75 ( = 0.387 )      (M1)A1

\n

[2 marks]

\n
a.
\n
\n

mean score = 2 × 3 + 3 × 15 + 4 × 28 + 5 × 17 + 6 × 9 + 7 × 3 75      (M1)

\n

= 323 75 ( = 4.31 )      A1

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.AHL.TZ2.H_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

A factory produces shirts. The cost, C, in Fijian dollars (FJD), of producing x shirts can be modelled by

\n

C(x) = (x − 75)2 + 100.

\n
\n

The cost of production should not exceed 500 FJD. To do this the factory needs to produce at least 55 shirts and at most s shirts.

\n
\n

Find the cost of producing 70 shirts.

\n
[2]
\n
a.
\n
\n

Find the value of s.

\n
[2]
\n
b.
\n
\n

Find the number of shirts produced when the cost of production is lowest.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(70 − 75)2 + 100     (M1)

\n

Note: Award (M1) for substituting in x = 70.

\n

125     (A1) (C2)

\n

[2 marks]

\n
a.
\n
\n

(s − 75)2 + 100 = 500     (M1)

\n

Note: Award (M1) for equating C(x) to 500. Accept an inequality instead of =.

\n

OR

\n

     (M1)

\n

 

\n

Note: Award (M1) for sketching correct graph(s).

\n

(s =) 95    (A1) (C2)

\n

[2 marks]

\n
b.
\n
\n

     (M1)

\n

Note: Award (M1) for an attempt at finding the minimum point using graph.

\n

OR

\n

\n\n\n95\n+\n55\n\n2\n\n     (M1)

\n

Note: Award (M1) for attempting to find the mid-point between their part (b) and 55.

\n

OR

\n

(C'(x) =) 2x − 150 = 0     (M1)

\n

Note: Award (M1) for an attempt at differentiation that is correctly equated to zero.

\n

75     (A1) (C2)

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ2.T_13", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Boat A is situated 10km away from boat B, and each boat has a marine radio transmitter on board. The range of the transmitter on boat A is 7km, and the range of the transmitter on boat B is 5km. The region in which both transmitters can be detected is represented by the shaded region in the following diagram. Find the area of this region.

\n

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

\n

use of cosine rule       (M1)

\n

CÂB = arccos  ( 49 + 100 25 2 × 7 × 10 ) = 0.48276 ( = 27.660 )       (A1)

\n

C B A = arccos  ( 25 + 100 49 2 × 5 × 10 ) = 0.70748 ( = 40.535 )       (A1)

\n

attempt to subtract triangle area from sector area       (M1)

\n

area  = 1 2 × 49 ( 2 C A B sin 2C A B ) + 1 2 × 25 ( 2 C B A sin 2C B A )

\n

= 3.5079… + 5.3385…      (A1)

\n

Note: Award this A1 for either of these two values.

\n

= 8.85 (km2)      A1

\n

Note: Accept all answers that round to 8.8 or 8.9.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.2.AHL.TZ0.H_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

Iron in the asteroid 16 Psyche is said to be valued at 8973 quadrillion euros EUR, where one quadrillion =1015.

\n
\n

James believes the asteroid is approximately spherical with radius 113km. He uses this information to estimate its volume.

\n
\n

Write down the value of the iron in the form a×10k where 1a<10 , k.

\n
[2]
\n
a.
\n
\n

Calculate James’s estimate of its volume, in km3.

\n
[2]
\n
b.
\n
\n

The actual volume of the asteroid is found to be 6.074×106km3.

\n

Find the percentage error in James’s estimate of the volume.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

8.97×1018  EUR  8.973×1018        (A1)(A1)  (C2)

\n

 

\n

Note: Award (A1) for 8.97 (8.973), (A1) for ×1018. Award (A1)(A0) for 8.97E18.
Award (A0)(A0) for answers of the type 8973×1015.

\n

 

\n

[2 marks]

\n
a.
\n
\n

4×π×11333       (M1)

\n


Note:
Award (M1) for correct substitution in volume of sphere formula.

\n


6040000 km3  6.04×106, 5771588π3, 6043992.82       (A1)  (C2) 

\n

[2 marks]

\n
b.
\n
\n

6043992.82-6.074×1066.074×106×100       (M1)

\n


Note:
Award (M1) for their correct substitution into the percentage error formula (accept a consistent absence of “×106” from all terms).

\n


0.494 %  0.494026%       (A1)(ft)  (C2) 

\n


Note: Follow through from their answer to part (b). If the final answer is negative, award at most (M1)(A0).

\n


[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Events \nA\n and \nB\n are such that \n\nP\n\n(\nA\n\nB\n)\n=\n0.95\n,\n\n P\n\n(\nA\n\nB\n)\n=\n0.6\n and \n\nP\n\n(\nA\n\n|\n\nB\n)\n=\n0.75\n.

\n
\n

Find \n\nP\n\n(\nB\n)\n.

\n
[2]
\n
a.
\n
\n

Find \n\nP\n\n(\nA\n)\n.

\n
[2]
\n
b.
\n
\n

Hence show that events \n\nA\n\n\n and \nB\n are independent.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nP\n\n(\nA\n\n|\n\nB\n)\n=\n\n\n\nP\n\n(\nA\n\nB\n)\n\n\n\nP\n\n(\nB\n)\n\n\n

\n

\n\n0.75\n=\n\n\n0.6\n\n\n\nP\n\n(\nB\n)\n\n\n     (M1)

\n

\n\n\nP\n\n(\nB\n)\n\n \n\n\n(\n\n=\n\n\n0.6\n\n\n0.75\n\n\n\n)\n\n=\n0.8\n     A1

\n

[2 marks]

\n
a.
\n
\n

\n\nP\n\n(\nA\n\nB\n)\n=\n\nP\n\n(\nA\n)\n+\n\nP\n\n(\nB\n)\n\n\nP\n\n(\nA\n\nB\n)\n

\n

\n\n0.95\n=\n\nP\n\n(\nA\n)\n+\n0.8\n\n0.6\n     (M1)

\n

\n\n\nP\n\n(\nA\n)\n=\n0.75\n     A1

\n

[2 marks]

\n
b.
\n
\n

METHOD 1

\n

\n\nP\n\n(\n\nA\n\n\n\n|\n\nB\n)\n=\n\n\n\nP\n\n(\n\nA\n\n\n\nB\n)\n\n\n\nP\n\n(\nB\n)\n\n\n=\n\n\n0.2\n\n\n0.8\n\n\n=\n0.25\n     A1

\n

\n\nP\n\n(\n\nA\n\n\n\n|\n\nB\n)\n=\n\nP\n\n(\n\nA\n\n\n)\n     R1

\n

hence \n\nA\n\n\n and \nB\n are independent     AG

\n

 

\n

Note:     If there is evidence that the student has calculated \n\nP\n\n(\n\nA\n\n\n\nB\n)\n=\n0.2\n by assuming independence in the first place, award A0R0.

\n

 

\n

METHOD 2

\n

EITHER

\n

\n\nP\n\n(\nA\n)\n=\n\nP\n\n(\nA\n\n|\n\nB\n)\n     A1

\n

OR

\n

\n\nP\n\n(\nA\n)\n×\n\nP\n\n(\nB\n)\n=\n0.75\n×\n0.80\n=\n0.6\n=\n\nP\n\n(\nA\n\nB\n)\n     A1

\n

THEN

\n

\nA\n and \nB\n are independent     R1

\n

hence \n\nA\n\n\n and \nB\n are independent     AG

\n

METHOD 3

\n

\n\nP\n\n(\n\nA\n\n\n)\n×\n\nP\n\n(\nB\n)\n=\n0.25\n×\n0.80\n=\n0.2\n     A1

\n

\n\nP\n\n(\n\nA\n\n\n)\n×\n\nP\n\n(\nB\n)\n=\n\nP\n\n(\n\nA\n\n\n\nB\n)\n     R1

\n

hence \n\nA\n\n\n and \nB\n are independent     AG

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.2.AHL.TZ0.H_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

In a triangle \n\nABC, AB\n\n=\n4\n\n cm, BC\n\n=\n3\n\n cm\n\n and \n\n\nB\n\n\nA\n^\n\n\nC\n\n\n=\n\nπ\n9\n\n.

\n
\n

Use the cosine rule to find the two possible values for AC.

\n
[5]
\n
a.
\n
\n

Find the difference between the areas of the two possible triangles ABC.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1

\n

let  AC = x

\n

3 2 = x 2 + 4 2 8 x cos π 9    M1A1

\n

attempting to solve for x     (M1)

\n

x = 1.09 ,   6.43    A1A1

\n

METHOD 2

\n

let  AC = x

\n

using the sine rule to find a value of C     M1

\n

4 2 = x 2 + 3 2 6 x cos ( 152.869 ) x = 1.09    (M1)A1

\n

4 2 = x 2 + 3 2 6 x cos ( 27.131 ) x = 6.43    (M1)A1

\n

METHOD 3

\n

let  AC = x

\n

using the sine rule to find a value of B and a value of C     M1

\n

obtaining B = 132.869 ,   7.131  and C = 27.131 ,   152.869      A1

\n

( B = 2.319 ,   0.124 and C = 0.473 ,   2.668 )

\n

attempting to find a value of x using the cosine rule     (M1)

\n

x = 1.09 ,   6.43    A1A1

\n

 

\n

Note: Award M1A0(M1)A1A0 for one correct value of x

\n

 

\n

[5 marks]

\n
a.
\n
\n

1 2 × 4 × 6.428 × sin π 9 and 1 2 × 4 × 1.088 × sin π 9      (A1)

\n

( 4.39747 and 0.744833 )

\n

let D be the difference between the two areas

\n

D = 1 2 × 4 × 6.428 × sin π 9 1 2 × 4 × 1.088 × sin π 9    (M1)

\n

( D = 4.39747 0.744833 )

\n

= 3.65  (c m 2 )    A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.2.AHL.TZ0.H_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule" ] }, { "Question": "
\n

Consider two events \nA\n and \nB\n such that \n\nP\n\n(\nA\n)\n=\nk\n,\n\n P\n\n(\nB\n)\n=\n3\nk\n,\n\n P\n\n(\nA\n\nB\n)\n=\n\n\nk\n2\n\n\n and \n\nP\n\n(\nA\n\nB\n)\n=\n0.5\n.

\n
\n

Calculate \nk\n;

\n
[3]
\n
a.
\n
\n

Find \n\nP\n\n(\n\nA\n\n\n\nB\n)\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

use of \n\nP\n\n(\nA\n\nB\n)\n=\n\nP\n\n(\nA\n)\n+\n\nP\n\n(\nB\n)\n\n\nP\n\n(\nA\n\nB\n)\n     M1

\n

\n0.5\n=\nk\n+\n3\nk\n\n\n\nk\n2\n\n\n     A1

\n

\n\n\nk\n2\n\n\n\n4\nk\n+\n0.5\n=\n0\n

\n

\nk\n=\n0.129\n     A1

\n

 

\n

Note:     Do not award the final A1 if two solutions are given.

\n

 

\n

[3 marks]

\n
a.
\n
\n

use of \n\nP\n\n(\n\nA\n\n\n\nB\n)\n=\n\nP\n\n(\nB\n)\n\n\nP\n\n(\nA\n\nB\n)\n or alternative     (M1)

\n

\n\nP\n\n(\n\nA\n\n\n\nB\n)\n=\n3\nk\n\n\n\nk\n2\n\n\n     (A1)

\n

\n=\n0.371\n     A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.AHL.TZ1.H_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Each of the 25 students in a class are asked how many pets they own. Two students own three pets and no students own more than three pets. The mean and standard deviation of the number of pets owned by students in the class are \n\n\n18\n\n\n25\n\n\n and \n\n\n24\n\n\n25\n\n\n respectively.

\n

Find the number of students in the class who do not own a pet.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

let p have no pets, q have one pet and r have two pets      (M1)

\n

p + q + r + 2 = 25      (A1)

\n

0p + 1q + 2r + 6 = 18      A1

\n

Note: Accept a statement that there are a total of 12 pets.

\n

attempt to use variance equation, or evidence of trial and error       (M1)

\n

\n\n\n0\np\n+\n1\nq\n+\n4\nr\n+\n18\n\n\n25\n\n\n\n\n\n\n(\n\n\n\n18\n\n\n25\n\n\n\n)\n\n2\n\n\n=\n\n\n\n(\n\n\n\n24\n\n\n25\n\n\n\n)\n\n2\n\n\n     (A1)

\n

attempt to solve a system of linear equations (M1)

\n

p = 14      A1

\n

 

\n

METHOD 2

\n

     (M1)

\n

\np\n+\nq\n+\nr\n+\n\n2\n\n25\n\n\n=\n1\n      (A1)

\n

\nq\n+\n2\nr\n+\n\n6\n\n25\n\n\n=\n\n\n18\n\n\n25\n\n\n\n(\n\n\nq\n+\n2\nr\n=\n\n\n12\n\n\n25\n\n\n\n)\n\n      A1

\n

\nq\n+\n4\nr\n+\n\n\n18\n\n\n25\n\n\n\n\n\n\n(\n\n\n\n18\n\n\n25\n\n\n\n)\n\n2\n\n\n=\n\n\n576\n\n\n625\n\n\n\n(\n\n\nq\n+\n4\nr\n=\n\n\n18\n\n\n25\n\n\n\n)\n\n      (M1)(A1)

\n

\nq\n=\n\n6\n\n25\n\n\n,\n\n\nr\n=\n\n3\n\n25\n\n\n      (M1)

\n

\np\n=\n\n\n14\n\n\n25\n\n\n       A1

\n

so 14 have no pets

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.AHL.TZ1.H_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Consider two events, \nA\n and \nB\n, such that \n\nP\n\n\n(\nA\n)\n\n=\n\nP\n\n\n(\n\n\nA\n\n\n\nB\n\n)\n\n=\n0.4\n and \n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n=\n0.1\n.

\n
\n

By drawing a Venn diagram, or otherwise, find \n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n.

\n
[3]
\n
a.
\n
\n

Show that the events \nA\n and \nB\n are not independent.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

        (M1)

\n

Note: Award M1 for a Venn diagram with at least one probability in the correct region.

\n

 

\n

EITHER

\n

\n\nP\n\n\n(\n\nA\n\n\nB\n\n\n\n)\n\n=\n0.3\n     (A1)

\n

\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n=\n0.3\n+\n0.4\n+\n0.1\n=\n0.8\n     A1

\n

OR

\n

\n\nP\n\n\n(\nB\n)\n\n=\n0.5\n     (A1)

\n

\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n=\n0.5\n+\n0.4\n\n0.1\n=\n0.8\n     A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

\n\nP\n\n\n(\nA\n)\n\n\nP\n\n\n(\nB\n)\n\n=\n0.4\n×\n0.5\n        (M1)

\n

= 0.2      A1

\n

statement that their \n\nP\n\n\n(\nA\n)\n\n\nP\n\n\n(\nB\n)\n\n\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n      R1

\n

Note: Award R1 for correct reasoning from their value.

\n

⇒ \nA\n, \nB\n not independent     AG

\n

 

\n

METHOD 2

\n

\n\nP\n\n\n(\n\n\n\nA\n|\n\nB\n\n)\n\n=\n\n\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n\n\n\nP\n\n\n(\nB\n)\n\n\n\n=\n\n\n0.1\n\n\n0.5\n\n\n        (M1)

\n

= 0.2      A1

\n

statement that their \n\nP\n\n\n(\n\n\n\nA\n|\n\nB\n\n)\n\n\n\nP\n\n\n(\nA\n)\n\n      R1

\n

Note: Award R1 for correct reasoning from their value.

\n

⇒ \nA\n, \nB\n not independent     AG

\n

Note: Accept equivalent argument using \n\nP\n\n\n(\n\n\n\nB\n|\n\nA\n\n)\n\n=\n0.25\n.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.1.AHL.TZ0.H_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The lengths of two of the sides in a triangle are 4 cm and 5 cm. Let θ be the angle between the two given sides. The triangle has an area of \n\n\n5\n\n15\n\n\n2\n\n cm2.

\n
\n

Show that \n\nsin\n\n\nθ\n=\n\n\n\n15\n\n\n4\n\n.

\n
[1]
\n
a.
\n
\n

Find the two possible values for the length of the third side.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

EITHER

\n

\n\n\n5\n\n15\n\n\n2\n\n=\n\n1\n2\n\n×\n4\n×\n5\n\n\nsin\n\n\nθ\n      A1

\n

OR

\n

height of triangle is \n\n\n5\n\n15\n\n\n4\n\n if using 4 as the base or \n\n\n15\n\n\n if using 5 as the base      A1

\n

THEN

\n

\n\nsin\n\n\nθ\n=\n\n\n\n15\n\n\n4\n\n        AG

\n

[1 mark]

\n
a.
\n
\n

let the third side be \nx\n

\n

\n\n\nx\n2\n\n\n=\n\n\n4\n2\n\n\n+\n\n\n5\n2\n\n\n\n2\n×\n4\n×\n5\n×\n\ncos\n\n\nθ\n       M1

\n

valid attempt to find \n\ncos\n\n\nθ\n       (M1)

\n

Note: Do not accept writing \n\ncos\n\n\n(\n\n\narcsin\n\n\n(\n\n\n\n\n15\n\n\n4\n\n\n)\n\n\n)\n\n as a valid method.

\n

\n\ncos\n\n\nθ\n=\n±\n\n1\n\n\n\n15\n\n\n16\n\n\n\n

\n

\n=\n\n1\n4\n\n\n,\n\n\n\n\n\n1\n4\n\n       A1A1

\n

\n\n\nx\n2\n\n\n=\n16\n+\n25\n\n2\n×\n4\n×\n5\n×\n±\n\n1\n4\n\n

\n

\nx\n=\n\n31\n\n  or  \n\n51\n\n       A1A1

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.AHL.TZ1.H_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The diagram shows the graph of the quadratic function f(x)=ax2+bx+c , with vertex 2, 10.

\n

\n

The equation f(x)=k has two solutions. One of these solutions is x=2.

\n
\n

Write down the other solution of f(x)=k.

\n
[2]
\n
a.
\n
\n

Complete the table below placing a tick (✔) to show whether the unknown parameters a and b are positive, zero or negative. The row for c has been completed as an example.

\n

\n
[2]
\n
b.
\n
\n

State the values of x for which f(x) is decreasing.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

x= -2-4  OR  x= -2-2--2      (M1)

\n


Note:
Award (M1) for correct calculation of the left symmetrical point.

\n


x= -6      (A1)   (C2)

\n


[2 marks]

\n
a.
\n
\n

      (A1)(A1)   (C2)

\n


Note:
Award (A1) for each correct row.

\n


[2 marks]

\n
b.
\n
\n

x>-2  OR  x-2      (A1)(A1)   (C2)

\n


Note:
Award (A1) for -2 seen as part of an inequality, (A1) for completely correct notation. Award (A1)(A1) for correct equivalent statement in words, for example “decreasing when x is greater than negative 2”.

\n


[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_11", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-6-quadratic-function" ] }, { "Question": "
\n

Consider the graph of the function fx=x2-kx.

\n
\n

The equation of the tangent to the graph of y=fx at x=-2 is 2y=4-5x.

\n
\n

Write down f(x).

\n
[3]
\n
a.
\n
\n

Write down the gradient of this tangent.

\n
[1]
\n
b.
\n
\n

Find the value of k.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

2x+kx2     (A1)(A1)(A1)    (C3)

\n


Note: Award (A1) for 2x, (A1) for +k, and (A1) for x-2 or 1x2.
Award at most (A1)(A1)(A0) if additional terms are seen.

\n

 

\n

[3 marks]

\n
a.
\n
\n

-2.5  -52     (A1)    (C1)

\n

[1 mark]

\n
b.
\n
\n

-2.5=2×-2+k-22       (M1)

\n


Note:
Award (M1) for equating their gradient from part (b) to their substituted derivative from part (a).

\n


k= 6      (A1)(ft)    (C2)

\n


Note:
Follow through from parts (a) and (b).

\n


[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_13", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Barry is at the top of a cliff, standing 80 m above sea level, and observes two yachts in the sea.
Seaview ( S ) is at an angle of depression of 25°.
Nauti Buoy ( N ) is at an angle of depression of 35°.
The following three dimensional diagram shows Barry and the two yachts at S and N.
X lies at the foot of the cliff and angle SXN = 70°.

\n

\"N17/5/MATHL/HP2/ENG/TZ0/05\"

\n

Find, to 3 significant figures, the distance between the two yachts.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to use tan, or sine rule, in triangle BXN or BXS     (M1)

\n

NX = 80 tan 55 ( = 80 tan 35 = 114.25 )     (A1)

\n

SX = 80 tan 65 ( = 80 tan 25 = 171.56 )     (A1)

\n

Attempt to use cosine rule     M1

\n

S N 2 = 171.56 2 + 114.25 2 2 × 171.56 × 114.25 cos 70 °     (A1)

\n

SN = 171   ( m )     A1

\n

 

\n

Note:     Award final A1 only if the correct answer has been given to 3 significant figures.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.2.AHL.TZ0.H_5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-3-applications-angles-of-elevation-and-depression-bearings" ] }, { "Question": "
\n

In the following diagram, \n\n\nOA\n\n\n\n = a, \n\n\nOB\n\n\n\n = b. C is the midpoint of [OA] and \n\n\nOF\n\n\n\n=\n\n1\n6\n\n\n\nFB\n\n\n\n.

\n

\"N17/5/MATHL/HP1/ENG/TZ0/09\"

\n
\n

It is given also that \n\n\nAD\n\n\n\n=\nλ\n\n\nAF\n\n\n\n and \n\n\nCD\n\n\n\n=\nμ\n\n\nCB\n\n\n\n, where \nλ\n,\n\n \n\nμ\n\n\nR\n\n.

\n
\n

Find, in terms of a and \n\n\nOF\n\n\n\n.

\n
[1]
\n
a.i.
\n
\n

Find, in terms of a and \n\n\nAF\n\n\n\n.

\n
[2]
\n
a.ii.
\n
\n

Find an expression for \n\n\nOD\n\n\n\n in terms of a, b and \nλ\n;

\n
[2]
\n
b.i.
\n
\n

Find an expression for \n\n\nOD\n\n\n\n in terms of a, b and \nμ\n.

\n
[2]
\n
b.ii.
\n
\n

Show that \nμ\n=\n\n1\n\n13\n\n\n, and find the value of \nλ\n.

\n
[4]
\n
c.
\n
\n

Deduce an expression for \n\n\nCD\n\n\n\n in terms of a and b only.

\n
[2]
\n
d.
\n
\n

Given that area \nΔ\n\nOAB\n\n=\nk\n(\n\narea \n\nΔ\n\nCAD\n\n)\n, find the value of \nk\n.

\n
[5]
\n
e.
\n
", "Markscheme": "
\n

\n\n\nOF\n\n\n\n=\n\n1\n7\n\nb     A1

\n

[1 mark]

\n
a.i.
\n
\n

\n\n\nAF\n\n\n\n=\n\n\nOF\n\n\n\n\n\n\nOA\n\n\n\n     (M1)

\n

\n=\n\n1\n7\n\nba     A1

\n

[2 marks]

\n
a.ii.
\n
\n

\n\n\nOD\n\n\n\n=\n a \n+\nλ\n\n(\n\n\n1\n7\n\nb\n\na\n\n)\n\n\n \n\n\n(\n\n=\n(\n1\n\nλ\n)\na\n+\n\nλ\n7\n\nb\n\n)\n\n     M1A1

\n

[2 marks]

\n
b.i.
\n
\n

\n\n\nOD\n\n\n\n=\n\n1\n2\n\n a \n+\nμ\n\n(\n\n\n\n1\n2\n\na\n+\nb\n\n)\n\n\n \n\n\n(\n\n=\n\n(\n\n\n1\n2\n\n\n\nμ\n2\n\n\n)\n\na\n+\nμ\nb\n\n)\n\n     M1A1

\n

[2 marks]

\n
b.ii.
\n
\n

equating coefficients:     M1

\n

\n\nλ\n7\n\n=\nμ\n,\n\n \n\n1\n\nλ\n=\n\n\n1\n\nμ\n\n2\n\n     A1

\n

solving simultaneously:     M1

\n

\nλ\n=\n\n7\n\n13\n\n\n,\n\n \n\nμ\n=\n\n1\n\n13\n\n\n     A1AG

\n

[4 marks]

\n
c.
\n
\n

\n\n\nCD\n\n\n\n=\n\n1\n\n13\n\n\n\n\nCB\n\n\n\n

\n

\n=\n\n1\n\n13\n\n\n\n(\n\nb\n\n\n1\n2\n\na\n\n)\n\n\n \n\n\n(\n\n=\n\n\n1\n\n26\n\n\na\n+\n\n1\n\n13\n\n\nb\n\n)\n\n     M1A1

\n

[2 marks]

\n
d.
\n
\n

METHOD 1

\n

\n\narea \n\nΔ\n\nACD\n\n=\n\n1\n2\n\n\nCD\n\n×\n\nAC\n\n×\nsin\n\n\n\nA\n\n\nC\n^\n\n\nB\n\n\n     (M1)

\n

\n\narea \n\nΔ\n\nACB\n\n=\n\n1\n2\n\n\nCB\n\n×\n\nAC\n\n×\nsin\n\n\n\nA\n\n\nC\n^\n\n\nB\n\n\n     (M1)

\n

\n\nratio \n\n\n\n\narea \n\nΔ\n\nACD\n\n\n\n\narea \n\nΔ\n\nACB\n\n\n\n=\n\n\n\nCD\n\n\n\n\nCB\n\n\n\n=\n\n1\n\n13\n\n\n     A1

\n

\nk\n=\n\n\n\narea \n\nΔ\n\nOAB\n\n\n\n\narea \n\nΔ\n\nCAD\n\n\n\n=\n\n\n13\n\n\n\narea \n\nΔ\n\nCAB\n\n\n\n×\n\narea \n\nΔ\n\nOAB\n\n     (M1)

\n

\n=\n13\n×\n2\n=\n26\n     A1

\n

 

\n

METHOD 2

\n

\n\narea \n\nΔ\n\nOAB\n\n=\n\n1\n2\n\n\n|\n\na\n×\nb\n\n|\n\n     A1

\n

\n\narea \n\nΔ\n\nCAD\n\n=\n\n1\n2\n\n\n|\n\n\n\nCA\n\n\n\n×\n\n\nCD\n\n\n\n\n|\n\n or \n\n1\n2\n\n\n|\n\n\n\nCA\n\n\n\n×\n\n\nAD\n\n\n\n\n|\n\n     M1

\n

\n=\n\n1\n2\n\n\n|\n\n\n1\n2\n\na\n×\n\n(\n\n\n\n1\n\n26\n\n\na\n+\n\n1\n\n13\n\n\nb\n\n)\n\n\n|\n\n

\n

\n=\n\n1\n2\n\n\n|\n\n\n1\n2\n\na\n×\n\n(\n\n\n\n1\n\n26\n\n\na\n\n)\n\n+\n\n1\n2\n\na\n×\n\n1\n\n13\n\n\nb\n\n|\n\n     (M1)

\n

\n=\n\n1\n2\n\n×\n\n1\n2\n\n×\n\n1\n\n13\n\n\n\n|\n\na\n×\nb\n\n|\n\n\n \n\n\n(\n\n=\n\n1\n\n52\n\n\n\n|\n\na\n×\nb\n\n|\n\n\n)\n\n     A1

\n

\n\narea \n\nΔ\n\nOAB\n\n=\nk\n(\n\narea \n\nΔ\n\nCAD\n\n)\n

\n

\n\n1\n2\n\n\n|\n\na\n×\nb\n\n|\n\n=\nk\n\n1\n\n52\n\n\n\n|\n\na\n×\nb\n\n|\n\n

\n

\nk\n=\n26\n     A1

\n

[5 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "17N.1.AHL.TZ0.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

Andre will play in the semi-final of a tennis tournament.

\n

If Andre wins the semi-final he will progress to the final. If Andre loses the semi-final, he will not progress to the final.

\n

If Andre wins the final, he will be the champion.

\n

The probability that Andre will win the semi-final is p. If Andre wins the semi-final, then the probability he will be the champion is 0.6.

\n
\n

The probability that Andre will not be the champion is 0.58.

\n
\n

Complete the values in the tree diagram.

\n

\n
[1]
\n
a.
\n
\n

Find the value of p.

\n
[2]
\n
b.
\n
\n

Given that Andre did not become the champion, find the probability that he lost in the semi-final.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

       (A1)   (C1)

\n


Note:
Award (A1) for the correct pair of probabilities.

\n

 

\n

[1 mark]

\n
a.
\n
\n

p×0.4+1-p=0.58       (M1)

\n


Note:
Award (M1) for multiplying and adding correct probabilities for losing equated to 0.58.

OR

p×0.6=1-0.58       (M1)

\n


Note:
 Award (M1) for multiplying correct probabilities for winning equated to 1-0.58  or  0.42.

p= 0.7       (A1)(ft)      (C2)

\n


Note: Follow through from their part (a). Award the final (A1)(ft) only if their p is within the range 0<p<1.

\n


[2 marks]

\n
b.
\n
\n

0.30.58 1-0.70.58       (A1)(ft)(A1)

\n


Note:
Award (A1)(ft) for their correct numerator. Follow through from part (b). Award (A1) for the correct denominator.

OR

0.30.3+0.7×0.4       (A1)(ft)(A1)(ft)

\n


Note:
 Award (A1)(ft) for their correct numerator. Follow through from part (b). Award (A1)(ft) for their correct calculation of Andre losing the semi-final or winning the semi-final and then losing in the final. Follow through from their parts (a) and (b).

1529 0.517, 0.517241, 51.7%       (A1)(ft)      (C3)

\n


Note: Follow through from parts (a) and (b).

\n


[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_14", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Jean-Pierre jumps out of an airplane that is flying at constant altitude. Before opening his parachute, he goes through a period of freefall.

\n

Jean-Pierre’s vertical speed during the time of freefall, S, in m s-1, is modelled by the following function.

\n

St=K-601.2-t , t0

\n

where t, is the number of seconds after he jumps out of the airplane, and K is a constant. A sketch of Jean-Pierre’s vertical speed against time is shown below.

\n

\n

Jean-Pierre’s initial vertical speed is 0m s-1.

\n
\n

Find the value of K.

\n
[2]
\n
a.
\n
\n

In the context of the model, state what the horizontal asymptote represents.

\n
[1]
\n
b.
\n
\n

Find Jean-Pierre’s vertical speed after 10 seconds. Give your answer in kmh1 .

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

0=K-601.20      (M1)

\n


Note:
Award (M1) for correctly substituted function equated to zero.

\n


K= 60      (A1)    (C2)

\n


[2 marks]

\n
a.
\n
\n

the (vertical) speed that Jean-Pierre is approaching (as t increases)     (A1)    (C1)
OR
the limit of the (vertical) speed of Jean-Pierre     (A1)    (C1)

\n


Note: Accept “maximum speed” or “terminal speed”.

\n


[1 mark]

\n
b.
\n
\n

S= 60-601.2-10     (M1)

\n


Note: Award (M1) for correctly substituted function.

\n


S= 50.3096m s-1     (A1)(ft)

\n


Note:
Follow through from part (a).

\n


181 km h-1  181.114km h-1     (A1)(ft)       (C3)

\n


Note: Award the final (A1)(ft) for correct conversion of their speed to kmh1.

\n


[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_12", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-9-exponential-and-logarithmic-functions" ] }, { "Question": "
\n

Find the value of \n\n\n4\n\n\n\n\n1\n\n\n\nx\n3\n\n\n\n\n\nd\n\nx\n\n.

\n
[3]
\n
a.
\n
\n

Illustrate graphically the inequality \n\n\n\nn\n=\n5\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n<\n\n\n4\n\n\n\n\n1\n\n\n\nx\n3\n\n\n\n\n\nd\n\nx\n\n<\n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n.

\n
[4]
\n
b.
\n
\n

Hence write down a lower bound for \n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n.

\n
[1]
\n
c.
\n
\n

Find an upper bound for \n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n4\n\n\n\n\n1\n\n\n\nx\n3\n\n\n\n\n\nd\n\nx\n\n=\n\n\n\nlim\n\n\n\nR\n\n\n\n\n\n\n\n4\nR\n\n\n\n1\n\n\n\nx\n3\n\n\n\n\n\nd\n\nx\n\n      (A1)

\n

Note: The above A1 for using a limit can be awarded at any stage.
Condone the use of \n\n\n\nlim\n\n\n\nx\n\n\n\n\n.

\n

Do not award this mark to candidates who use \n\n as the upper limit throughout.

\n

= \n\n\n\nlim\n\n\n\nR\n\n\n\n\n\n\n\n[\n\n\n\n1\n2\n\n\n\nx\n\n\n2\n\n\n\n\n]\n\n4\nR\n\n\n(\n\n=\n\n\n[\n\n\n\n1\n2\n\n\n\nx\n\n\n2\n\n\n\n\n]\n\n4\n\n\n\n)\n\n     M1

\n

\n=\n\n\n\nlim\n\n\n\nR\n\n\n\n\n\n\n(\n\n\n\n1\n2\n\n\n(\n\n\n\nR\n\n\n2\n\n\n\n\n\n\n4\n\n\n2\n\n\n\n\n)\n\n\n)\n\n

\n

\n=\n\n1\n\n32\n\n\n     A1

\n

[3 marks]

\n
a.
\n
\n

      A1A1A1A1

\n

A1 for the curve
A1 for rectangles starting at \nx\n=\n4\n
A1 for at least three upper rectangles
A1 for at least three lower rectangles

\n

Note: Award A0A1 for two upper rectangles and two lower rectangles.

\n

sum of areas of the lower rectangles < the area under the curve < the sum of the areas of the upper rectangles so

\n

\n\n\n\nn\n=\n5\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n<\n\n\n4\n\n\n\n\n1\n\n\n\nx\n3\n\n\n\n\n\nd\n\nx\n\n<\n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n      AG

\n

[4 marks]

\n
b.
\n
\n

a lower bound is \n\n1\n\n32\n\n\n     A1

\n

Note: Allow FT from part (a).

\n

[1 mark]

\n
c.
\n
\n

METHOD 1

\n

\n\n\n\nn\n=\n5\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n<\n\n1\n\n32\n\n\n    (M1)

\n

\n\n1\n\n64\n\n\n+\n\n\n\nn\n=\n5\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n=\n\n1\n\n32\n\n\n+\n\n1\n\n64\n\n\n     (M1)

\n

\n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n<\n\n3\n\n64\n\n\n, an upper bound      A1

\n

Note: Allow FT from part (a).

\n

 

\n

METHOD 2

\n

changing the lower limit in the inequality in part (b) gives

\n

\n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n<\n\n\n3\n\n\n\n\n1\n\n\n\nx\n3\n\n\n\n\n\nd\n\nx\n\n\n(\n\n<\n\n\n\nn\n=\n3\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n\n)\n\n     (A1)

\n

\n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n<\n\n\n\nlim\n\n\n\nR\n\n\n\n\n\n\n\n[\n\n\n\n1\n2\n\n\n\nx\n\n\n2\n\n\n\n\n]\n\n3\nR\n\n     (M1)

\n

\n\n\n\nn\n=\n4\n\n\n\n\n\n1\n\n\n\nn\n3\n\n\n\n\n\n<\n\n1\n\n18\n\n\n, an upper bound     A1

\n

Note: Condone candidates who do not use a limit.

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18M.3.AHL.TZ0.HCA_3", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Consider the differential equation \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n+\n\nx\n\n\n\nx\n2\n\n\n+\n1\n\n\ny\n=\nx\n where \ny\n=\n1\n when \nx\n=\n0\n.

\n
\n

Show that \n\n\n\nx\n2\n\n\n+\n1\n\n is an integrating factor for this differential equation.

\n
[4]
\n
a.
\n
\n

Solve the differential equation giving your answer in the form \ny\n=\nf\n(\nx\n)\n.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

integrating factor \n=\n\n\n\ne\n\n\n\n\n\nx\n\n\n\nx\n2\n\n\n+\n1\n\n\n\nd\n\nx\n\n\n\n\n     (M1)

\n

\n\n\n\nx\n\n\n\nx\n2\n\n\n+\n1\n\n\n\nd\n\nx\n=\n\n1\n2\n\nln\n\n(\n\n\nx\n2\n\n\n+\n1\n)\n\n     (M1)

\n

 

\n

Note:     Award M1 for use of \nu\n=\n\n\nx\n2\n\n\n+\n1\n for example or \n\n\n\n\n\nf\n\n\n(\nx\n)\n\n\nf\n(\nx\n)\n\n\n\nd\n\nx\n=\nln\n\nf\n(\nx\n)\n\n.

\n

 

\n

integrating factor \n=\n\n\n\ne\n\n\n\n1\n2\n\nln\n\n(\n\n\nx\n2\n\n\n+\n1\n)\n\n\n\n     A1

\n

\n=\n\n\n\ne\n\n\nln\n\n\n(\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n)\n\n\n\n\n     A1

\n

 

\n

Note:     Award A1 for \n\n\n\ne\n\n\nln\n\n\nu\n\n\n\n\n where \nu\n=\n\n\nx\n2\n\n\n+\n1\n.

\n

 

\n

\n=\n\n\n\nx\n2\n\n\n+\n1\n\n     AG

\n

 

\n

METHOD 2

\n

\n\n\nd\n\n\n\nd\n\nx\n\n\n\n(\n\ny\n\n\n\nx\n2\n\n\n+\n1\n\n\n)\n\n=\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n\n\nx\n2\n\n\n+\n1\n\n+\n\nx\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n\ny\n     M1A1

\n

\n\n\n\nx\n2\n\n\n+\n1\n\n\n(\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n+\n\nx\n\n\n\nx\n2\n\n\n+\n1\n\n\ny\n\n)\n\n     M1A1

\n

 

\n

Note:     Award M1 for attempting to express in the form \n\n\n\nx\n2\n\n\n+\n1\n\n×\n\n(LHS of de)\n\n.

\n

 

\n

so \n\n\n\nx\n2\n\n\n+\n1\n\n is an integrating factor for this differential equation     AG

\n

[4 marks]

\n
a.
\n
\n

\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n+\n\nx\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n\ny\n=\nx\n\n\n\nx\n2\n\n\n+\n1\n\n (or equivalent)     (M1)

\n

\n\n\nd\n\n\n\nd\n\nx\n\n\n\n(\n\ny\n\n\n\nx\n2\n\n\n+\n1\n\n\n)\n\n=\nx\n\n\n\nx\n2\n\n\n+\n1\n\n

\n

\ny\n\n\n\nx\n2\n\n\n+\n1\n\n=\n\n\nx\n\n\n\nx\n2\n\n\n+\n1\n\n\nd\n\nx\n\n \n\n\n(\n\ny\n=\n\n1\n\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n\n\nx\n\n\n\nx\n2\n\n\n+\n1\n\n\nd\n\nx\n\n\n)\n\n\n     A1

\n

\n=\n\n1\n3\n\n\n(\n\n\nx\n2\n\n\n+\n1\n\n)\n\n\n3\n2\n\n\n\n\n+\nC\n     (M1)A1

\n

 

\n

Note:     Award M1 for using an appropriate substitution.

\n

 

\n

Note:     Condone the absence of \nC\n.

\n

 

\n

substituting \nx\n=\n0\n,\n\n \n\ny\n=\n1\n\nC\n=\n\n2\n3\n\n     M1

\n

 

\n

Note:     Award M1 for attempting to find their value of \nC\n.

\n

 

\n

\ny\n=\n\n1\n3\n\n(\n\n\nx\n2\n\n\n+\n1\n)\n+\n\n2\n\n3\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n\n \n\n\n(\n\ny\n=\n\n\n\n\n\n(\n\n\nx\n2\n\n\n+\n1\n)\n\n\n\n3\n2\n\n\n\n\n+\n2\n\n\n3\n\n\n\nx\n2\n\n\n+\n1\n\n\n\n\n)\n\n     A1

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.3.AHL.TZ0.HCA_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

Let \nA\n be the set \n{\nx\n\n|\n\nx\n\n\nR\n\n,\n\n \n\nx\n\n0\n}\n. Let \nB\n be the set \n{\nx\n\n|\n\nx\n\n]\n\n1\n,\n\n \n\n+\n1\n[\n,\n\n \n\nx\n\n0\n}\n.

\n

A function \nf\n:\nA\n\nB\n is defined by \nf\n(\nx\n)\n=\n\n2\nπ\n\narctan\n\n(\nx\n)\n.

\n
\n

Let \nD\n be the set \n{\nx\n\n|\n\nx\n\n\nR\n\n,\n\n \n\nx\n>\n0\n}\n.

\n

A function \ng\n:\n\nR\n\n\nD\n is defined by \ng\n(\nx\n)\n=\n\n\n\ne\n\nx\n\n\n.

\n
\n

(i)     Sketch the graph of \ny\n=\nf\n(\nx\n)\n and hence justify whether or not \nf\n is a bijection.

\n

(ii)     Show that \nA\n is a group under the binary operation of multiplication.

\n

(iii)     Give a reason why \nB\n is not a group under the binary operation of multiplication.

\n

(iv)     Find an example to show that \nf\n(\na\n×\nb\n)\n=\nf\n(\na\n)\n×\nf\n(\nb\n)\n is not satisfied for all \na\n,\n\n \n\nb\n\nA\n.

\n
[13]
\n
a.
\n
\n

(i)     Sketch the graph of \ny\n=\ng\n(\nx\n)\n and hence justify whether or not \ng\n is a bijection.

\n

(ii)     Show that \ng\n(\na\n+\nb\n)\n=\ng\n(\na\n)\n×\ng\n(\nb\n)\n for all \na\n,\n\n \n\nb\n\n\nR\n\n.

\n

(iii)     Given that \n{\n\nR\n\n,\n\n \n\n+\n}\n and \n{\nD\n,\n\n \n\n×\n}\n are both groups, explain whether or not they are isomorphic.

\n
[8]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(i)     \"N16/5/MATHL/HP3/ENG/TZ0/SG/M/02.a.i\"     A1

\n

 

\n

Notes: Award A1 for general shape, labelled asymptotes, and showing that \nx\n\n0\n.

\n

 

\n

graph shows that it is injective since it is increasing or by the horizontal line test     R1

\n

graph shows that it is surjective by the horizontal line test     R1

\n

 

\n

Note: Allow any convincing reasoning.

\n

 

\n

so \nf\n is a bijection     A1

\n

(ii)     closed since non-zero real times non-zero real equals non-zero real     A1R1

\n

we know multiplication is associative     R1

\n

identity is 1     A1

\n

inverse of \nx\n is \n\n1\nx\n\n(\nx\n\n0\n)\n     A1

\n

hence it is a group     AG

\n

(iii)     \nB\n does not have an identity     A2

\n

hence it is not a group     AG

\n

(iv)     \nf\n(\n1\n×\n1\n)\n=\nf\n(\n1\n)\n=\n\n1\n2\n\n whereas \nf\n(\n1\n)\n×\nf\n(\n1\n)\n=\n\n1\n2\n\n×\n\n1\n2\n\n=\n\n1\n4\n\n is one counterexample     A2

\n

hence statement is not satisfied     AG

\n

[13 marks]

\n
a.
\n
\n

\"N16/5/MATHL/HP3/ENG/TZ0/SG/M/02.b\"

\n

award A1 for general shape going through (0, 1) and with domain \n\nR\n\n     A1

\n

graph shows that it is injective since it is increasing or by the horizontal line test and graph shows that it is surjective by the horizontal line test     R1

\n

 

\n

Note: Allow any convincing reasoning.

\n

 

\n

so \ng\n  is a bijection     A1

\n

(ii)     \ng\n(\na\n+\nb\n)\n=\n\n\n\ne\n\n\na\n+\nb\n\n\n\n and \ng\n(\na\n)\n×\ng\n(\nb\n)\n=\n\n\n\ne\n\na\n\n\n×\n\n\n\ne\n\nb\n\n\n=\n\n\n\ne\n\n\na\n+\nb\n\n\n\n     M1A1

\n

hence \ng\n(\na\n+\nb\n)\n=\ng\n(\na\n)\n×\ng\n(\nb\n)\n     AG

\n

(iii)     since \ng\n is a bijection and the homomorphism rule is obeyed     R1R1

\n

the two groups are isomorphic     A1

\n

[8 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.3.AHL.TZ0.HSRG_2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

Consider the differential equation \nx\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\ny\n=\n\n\nx\np\n\n\n+\n1\n where \nx\n\n\nR\n\n,\n\nx\n\n0\n and \np\n is a positive integer, \np\n>\n1\n.

\n
\n

Solve the differential equation given that \ny\n=\n\n1\n when \nx\n=\n1\n. Give your answer in the form \ny\n=\nf\n\n(\nx\n)\n\n.

\n
[8]
\n
a.
\n
\n

Show that the \nx\n-coordinate(s) of the points on the curve \ny\n=\nf\n\n(\nx\n)\n\n where \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n satisfy the equation \n\n\nx\n\np\n\n1\n\n\n\n=\n\n1\np\n\n.

\n
[2]
\n
b.i.
\n
\n

Deduce the set of values for \np\n such that there are two points on the curve \ny\n=\nf\n\n(\nx\n)\n\n where \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n. Give a reason for your answer.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\ny\nx\n\n=\n\n\nx\n\np\n\n1\n\n\n\n+\n\n1\nx\n\n    (M1)

\n

integrating factor \n=\n\n\n\ne\n\n\n\n\n\n\n1\nx\n\n\nd\n\nx\n\n\n\n\n     M1

\n

\n\n = \n\n\n\n\ne\n\n\n\n\nln\n\n\nx\n\n\n\n     (A1)

\n

\n\n1\nx\n\n     A1

\n

\n\n1\nx\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n\ny\n\n\n\nx\n2\n\n\n\n\n=\n\n\nx\n\np\n\n2\n\n\n\n+\n\n1\n\n\n\nx\n2\n\n\n\n\n     (M1)

\n

\n\n\nd\n\n\n\nd\n\nx\n\n\n\n(\n\n\ny\nx\n\n\n)\n\n=\n\n\nx\n\np\n\n2\n\n\n\n+\n\n1\n\n\n\nx\n2\n\n\n\n\n

\n

\n\ny\nx\n\n=\n\n1\n\np\n\n1\n\n\n\n\nx\n\np\n\n1\n\n\n\n\n\n1\nx\n\n+\nC\n    A1

\n

Note: Condone the absence of C.

\n

\ny\n=\n\n1\n\np\n\n1\n\n\n\n\nx\np\n\n\n+\nC\nx\n\n1\n

\n

substituting \nx\n=\n1\n\ny\n=\n\n1\n\nC\n=\n\n\n1\n\np\n\n1\n\n\n    M1 

\n

Note: Award M1 for attempting to find their value of C.

\n

\ny\n=\n\n1\n\np\n\n1\n\n\n\n(\n\n\n\nx\np\n\n\n\nx\n\n)\n\n\n1\n      A1

\n

[8 marks]

\n

 

\n

METHOD 2

\n

put \ny\n=\nv\nx\n so that \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n    M1(A1)

\n

substituting,       M1 

\n

\nx\n\n(\n\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n\n)\n\n\nv\nx\n=\n\n\nx\np\n\n\n+\n1\n     (A1)

\n

\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\n\nx\n\np\n\n1\n\n\n\n+\n\n1\nx\n\n      M1

\n

\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\n\nx\n\np\n\n2\n\n\n\n+\n\n1\n\n\n\nx\n2\n\n\n\n\n

\n

\nv\n=\n\n1\n\np\n\n1\n\n\n\n\nx\n\np\n\n1\n\n\n\n\n\n1\nx\n\n+\nC\n     A1

\n

Note: Condone the absence of C.

\n

\ny\n=\n\n1\n\np\n\n1\n\n\n\n\nx\np\n\n\n+\nC\nx\n\n1\n

\n

substituting \nx\n=\n1\n\ny\n=\n\n1\n\nC\n=\n\n\n1\n\np\n\n1\n\n\n    M1 

\n

Note: Award M1 for attempting to find their value of C.

\n

\ny\n=\n\n1\n\np\n\n1\n\n\n\n(\n\n\n\nx\np\n\n\n\nx\n\n)\n\n\n1\n      A1

\n

[8 marks]

\n
a.
\n
\n

METHOD 1

\n

find \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n and solve \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n for \nx\n

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n1\n\np\n\n1\n\n\n\n(\n\np\n\n\nx\n\np\n\n1\n\n\n\n\n1\n\n)\n\n     M1

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n\np\n\n\nx\n\np\n\n1\n\n\n\n\n1\n=\n0\n     A1

\n

\np\n\n\nx\n\np\n\n1\n\n\n\n=\n1\n

\n

Note: Award a maximum of M1A0 if a candidate’s answer to part (a) is incorrect.

\n

\n\n\nx\n\np\n\n1\n\n\n\n=\n\n1\np\n\n     AG

\n

 

\n

METHOD 2

\n

substitute \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n and their \ny\n into the differential equation and solve for \nx\n

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n\n\n\n(\n\n\n\n\n\nx\np\n\n\n\nx\n\n\np\n\n1\n\n\n\n)\n\n+\n1\n=\n\n\nx\np\n\n\n+\n1\n     M1

\n

\n\n\nx\np\n\n\n\nx\n=\n\n\nx\np\n\n\n\np\n\n\nx\np\n\n\n     A1

\n

\np\n\n\nx\n\np\n\n1\n\n\n\n=\n1\n

\n

Note: Award a maximum of M1A0 if a candidate’s answer to part (a) is incorrect.

\n

\n\n\nx\n\np\n\n1\n\n\n\n=\n\n1\np\n\n     AG

\n

[2 marks]

\n

 

\n
b.i.
\n
\n

there are two solutions for \nx\n when \np\n is odd (and \np\n>\n1\n     A1

\n

if \np\n\n1\n is even there are two solutions (to \n\n\nx\n\np\n\n1\n\n\n\n=\n\n1\np\n\n)

\n

and if \np\n\n1\n is odd there is only one solution (to \n\n\nx\n\np\n\n1\n\n\n\n=\n\n1\np\n\n)   R1

\n

Note: Only award the R1 if both cases are considered.

\n

[4 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18M.3.AHL.TZ0.HCA_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

Consider the differential equation \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n1\n+\n\ny\nx\n\n, where \nx\n\n0\n.

\n
\n

Consider the family of curves which satisfy the differential equation \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n1\n+\n\ny\nx\n\n, where \nx\n\n0\n.

\n
\n

Given that \ny\n\n(\n1\n)\n\n=\n1\n, use Euler’s method with step length \nh\n = 0.25 to find an approximation for \ny\n\n(\n2\n)\n\n. Give your answer to two significant figures.

\n
[4]
\n
a.
\n
\n

Solve the equation \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n1\n+\n\ny\nx\n\n for \ny\n\n(\n1\n)\n\n=\n1\n.

\n
[6]
\n
b.
\n
\n

Find the percentage error when \ny\n\n(\n2\n)\n\n is approximated by the final rounded value found in part (a). Give your answer to two significant figures.

\n
[3]
\n
c.
\n
\n

Find the equation of the isocline corresponding to \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\nk\n, where \nk\n\n0\n\nk\n\n\nR\n\n.

\n
[1]
\n
d.i.
\n
\n

Show that such an isocline can never be a normal to any of the family of curves that satisfy the differential equation.

\n
[4]
\n
d.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to apply Euler’s method         (M1)

\n

\n\n\nx\n\nn\n+\n1\n\n\n\n=\n\n\nx\nn\n\n\n+\n0.25\n\n;\n\n\n\n\n\ny\n\nn\n+\n1\n\n\n\n=\n\n\ny\nn\n\n\n+\n0.25\n×\n\n(\n\n1\n+\n\n\n\n\ny\nn\n\n\n\n\n\n\nx\nn\n\n\n\n\n\n)\n\n

\n

     (A1)(A1)

\n

Note: Award A1 for correct \nx\n values, A1 for first three correct \ny\n values.

\n

 

\n

\ny\n = 3.3      A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

METHOD 1

\n

\nI\n\n(\nx\n)\n\n=\n\n\n\ne\n\n\n\n\n\n\n1\nx\n\n\nd\n\nx\n\n\n\n\n       (M1)

\n

\n=\n\n\n\ne\n\n\n\n\nln\n\n\nx\n\n\n\n

\n

\n=\n\n1\nx\n\n       (A1)

\n

\n\n1\nx\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n\ny\n\n\n\nx\n2\n\n\n\n\n=\n\n1\nx\n\n       (M1)

\n

\n\n\nd\n\n\n\nd\n\nx\n\n\n\n(\n\n\ny\nx\n\n\n)\n\n=\n\n1\nx\n\n

\n

\n\ny\nx\n\n=\n\nln\n\n\n|\nx\n|\n\n+\nC\n       A1

\n

\ny\n\n(\n1\n)\n\n=\n1\n\nC\n=\n1\n       M1

\n

\ny\n=\nx\n\n\nln\n\n\n|\nx\n|\n\n+\nx\n       A1

\n

 

\n

METHOD 2

\n

\nv\n=\n\ny\nx\n\n       M1

\n

\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\n1\nx\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n\n\n1\n\n\n\nx\n2\n\n\n\n\ny\n       (A1)

\n

\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n1\n+\nv\n       M1

\n

\n\n1\n\n\nd\n\nv\n=\n\n\n\n1\nx\n\n\n\n\nd\n\nx\n

\n

\nv\n=\n\nln\n\n\n|\nx\n|\n\n+\nC\n

\n

\n\ny\nx\n\n=\n\nln\n\n\n|\nx\n|\n\n+\nC\n       A1

\n

\ny\n\n(\n1\n)\n\n=\n1\n\nC\n=\n1\n       M1

\n

\ny\n=\nx\n\n\nln\n\n\n|\nx\n|\n\n+\nx\n       A1

\n

 

\n

[6 marks]

\n
b.
\n
\n

\ny\n\n(\n2\n)\n\n=\n2\n\n\nln\n\n\n2\n+\n2\n=\n3.38629\n\n

\n

percentage error \n=\n\n\n3.38629\n\n\n3.3\n\n\n3.38629\n\n\n\n×\n100\n\n\n\n      (M1)(A1)

\n

= 2.5%       A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\nk\n\n1\n+\n\ny\nx\n\n=\nk\n      A1

\n

\ny\n=\n\n(\n\nk\n\n1\n\n)\n\nx\n

\n

 

\n

[1 mark]

\n
d.i.
\n
\n

gradient of isocline equals gradient of normal        (M1)

\n

\nk\n\n1\n=\n\n\n1\nk\n\n or \nk\n\n(\n\nk\n\n1\n\n)\n\n=\n\n1\n      A1

\n

\n\n\nk\n2\n\n\n\nk\n+\n1\n=\n0\n       A1

\n

\nΔ\n=\n1\n\n4\n<\n0\n       R1

\n

\n\n no solution       AG

\n

Note: Accept alternative reasons for no solutions.

\n

 

\n

[4 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "18N.3.AHL.TZ0.HCA_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

Consider the differential equation

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\nf\n\n(\n\n\ny\nx\n\n\n)\n\n,\n\n \n\nx\n>\n0.\n

\n

Use the substitution \ny\n=\nv\nx\n to show that the general solution of this differential equation is

\n

\n\n\n\n\n\nd\n\nv\n\n\nf\n(\nv\n)\n\nv\n\n\n=\nln\n\nx\n+\n\n\n Constant.\n\n

\n
[3]
\n
a.
\n
\n

Hence, or otherwise, solve the differential equation

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n\n\nx\n2\n\n\n+\n3\nx\ny\n+\n\n\ny\n2\n\n\n\n\n\n\nx\n2\n\n\n\n\n,\n\n \n\nx\n>\n0\n,\n

\n

given that \ny\n=\n1\n when \nx\n=\n1\n. Give your answer in the form \ny\n=\ng\n(\nx\n)\n.

\n
[10]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\ny\n=\nv\nx\n\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n     M1

\n

the differential equation becomes

\n

\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\nf\n(\nv\n)\n     A1

\n

\n\n\n\n\n\nd\n\nv\n\n\nf\n(\nv\n)\n\nv\n\n\n=\n\n\n\n\n\nd\n\nv\n\nx\n\n\n\n     A1

\n

integrating, Constant \n\n\n\n\n\nd\n\nv\n\n\nf\n(\nv\n)\n\nv\n\n\n=\nln\n\nx\n+\n\n\n Constant\n\n     AG

\n

[3 marks]

\n
a.
\n
\n

EITHER

\n

\nf\n(\nv\n)\n=\n1\n+\n3\nv\n+\n\n\nv\n2\n\n\n     (A1)

\n

\n\n(\n\n\n\n\n\n\nd\n\nv\n\n\nf\n(\nv\n)\n\nv\n\n\n=\n\n\n)\n\n\n\n\n\n\n\n\n\nd\n\nv\n\n\n1\n+\n3\nv\n+\n\n\nv\n2\n\n\n\nv\n\n\n=\nln\n\nx\n+\nC\n\n     M1A1

\n

\n\n\n\n\n\nd\n\nv\n\n\n\n\n\n(\n1\n+\nv\n)\n\n2\n\n\n\n\n=\n(\nln\n\nx\n+\nC\n)\n\n     A1

\n

 

\n

Note:     A1 is for correct factorization.

\n

 

\n

\n\n\n1\n\n1\n+\nv\n\n\n\n\n\n(\n=\nln\n\nx\n+\nC\n)\n     A1

\n

OR

\n

\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n1\n+\n3\nv\n+\n\n\nv\n2\n\n\n     A1

\n

\n\n\n\n\n\nd\n\nv\n\n\n1\n+\n2\nv\n+\n\n\nv\n2\n\n\n\n\n=\n\n\n\n1\nx\n\n\nd\n\nx\n\n\n     M1

\n

\n\n\n\n\n\nd\n\nv\n\n\n\n\n\n(\n1\n+\nv\n)\n\n2\n\n\n\n\n\n\n\n\n(\n\n=\n\n\n\n1\nx\n\n\nd\n\nx\n\n\n)\n\n\n     (A1)

\n

 

\n

Note:     A1 is for correct factorization.

\n

 

\n

\n\n\n1\n\n1\n+\nv\n\n\n=\nln\n\nx\n(\n+\nC\n)\n     A1A1

\n

THEN

\n

substitute \ny\n=\n1\n or \nv\n=\n1\n when \nx\n=\n1\n     (M1)

\n

therefore \nC\n=\n\n\n1\n2\n\n     A1

\n

 

\n

Note:     This A1 can be awarded anywhere in their solution.

\n

 

\n

substituting for \nv\n,

\n

\n\n\n1\n\n\n(\n\n1\n+\n\ny\nx\n\n\n)\n\n\n\n=\nln\n\nx\n\n\n1\n2\n\n     M1

\n

 

\n

Note:     Award for correct substitution of \n\ny\nx\n\n into their expression.

\n

 

\n

\n1\n+\n\ny\nx\n\n=\n\n1\n\n\n1\n2\n\n\nln\n\nx\n\n\n     (A1)

\n

 

\n

Note:     Award for any rearrangement of a correct expression that has \ny\n in the numerator.

\n

 

\n

\ny\n=\nx\n\n(\n\n\n1\n\n\n(\n\n\n1\n2\n\n\nln\n\nx\n\n)\n\n\n\n\n1\n\n)\n\n\n\n\n\n(or equivalent)\n\n     A1

\n

\n\n(\n\n=\nx\n\n(\n\n\n\n1\n+\n2\nln\n\nx\n\n\n1\n\n2\nln\n\nx\n\n\n\n)\n\n\n)\n\n

\n

[10 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.3.AHL.TZ0.HCA_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

Two submarines A and B have their routes planned so that their positions at time t hours, 0 ≤ t < 20 , would be defined by the position vectors rA \n=\n\n(\n\n\n\n\n2\n\n\n\n\n\n4\n\n\n\n\n\n1\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n1\n\n\n\n\n\n1\n\n\n\n\n\n0.15\n\n\n\n)\n\n and rB \n=\n\n(\n\n\n\n\n0\n\n\n\n\n\n3.2\n\n\n\n\n\n2\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n0.5\n\n\n\n\n\n1.2\n\n\n\n\n\n0.1\n\n\n\n)\n\n relative to a fixed point on the surface of the ocean (all lengths are in kilometres).

\n
\n

To avoid the collision submarine B adjusts its velocity so that its position vector is now given by

\n

rB \n=\n\n(\n\n\n\n\n0\n\n\n\n\n\n3.2\n\n\n\n\n\n2\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n0.45\n\n\n\n\n\n1.08\n\n\n\n\n\n0.09\n\n\n\n)\n\n.

\n
\n

Show that the two submarines would collide at a point P and write down the coordinates of P.

\n
[4]
\n
a.
\n
\n

Show that submarine B travels in the same direction as originally planned.

\n
[1]
\n
b.i.
\n
\n

Find the value of t when submarine B passes through P.

\n
[2]
\n
b.ii.
\n
\n

Find an expression for the distance between the two submarines in terms of t.

\n
[5]
\n
c.i.
\n
\n

Find the value of t when the two submarines are closest together.

\n
[2]
\n
c.ii.
\n
\n

Find the distance between the two submarines at this time.

\n
[1]
\n
c.iii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

rA rB        (M1)

\n

2 − t = − 0.5t ⇒ t = 4       A1

\n

checking t = 4 satisfies 4 + t = 3.2 + 1.2t and − 1 − 0.15t = − 2 + 0.1t      R1

\n

P(−2, 8, −1.6)      A1

\n

Note: Do not award final A1 if answer given as column vector.

\n

[4 marks]

\n
a.
\n
\n

\n0.9\n×\n\n(\n\n\n\n\n0.5\n\n\n\n\n\n1.2\n\n\n\n\n\n0.1\n\n\n\n)\n\n=\n\n(\n\n\n\n\n0.45\n\n\n\n\n\n1.08\n\n\n\n\n\n0.09\n\n\n\n)\n\n     A1

\n

Note: Accept use of cross product equalling zero.

\n

hence in the same direction      AG

\n

[1 mark]

\n
b.i.
\n
\n

\n\n(\n\n\n\n\n\n0.45\nt\n\n\n\n\n3.2\n+\n1.08\nt\n\n\n\n\n\n2\n+\n0.09\nt\n\n\n\n)\n\n=\n\n(\n\n\n\n\n2\n\n\n\n\n\n8\n\n\n\n\n\n1.6\n\n\n\n)\n\n      M1

\n

Note: The M1 can be awarded for any one of the resultant equations.

\n

\n\nt\n=\n\n\n40\n\n9\n\n=\n4.44\n\n     A1

\n

[2 marks]

\n
b.ii.
\n
\n

rA − rB\n\n(\n\n\n\n\n2\n\nt\n\n\n\n\n\n4\n+\nt\n\n\n\n\n\n1\n\n0.15\nt\n\n\n\n)\n\n\n\n(\n\n\n\n\n\n0.45\nt\n\n\n\n\n3.2\n+\n1.08\nt\n\n\n\n\n\n2\n+\n0.09\nt\n\n\n\n)\n\n      (M1)(A1)

\n

\n=\n\n(\n\n\n\n\n2\n\n0.55\nt\n\n\n\n\n\n0.8\n\n0.08\nt\n\n\n\n\n1\n\n0.24\nt\n\n\n\n)\n\n     (A1)

\n

Note: Accept rA − rB.

\n

distance \nD\n=\n\n\n\n\n\n(\n\n2\n\n0.55\nt\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n0.8\n\n0.08\nt\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n1\n\n0.24\nt\n\n)\n\n\n2\n\n\n\n      M1A1

\n

\n\n(\n\n=\n\n8.64\n\n2.688\nt\n+\n0.317\n\n\nt\n2\n\n\n\n\n)\n\n

\n

[5 marks]

\n
c.i.
\n
\n

minimum when \n\n\n\nd\n\nD\n\n\n\nd\n\nt\n\n\n=\n0\n      (M1)

\n

t = 3.83      A1

\n

[2 marks]

\n
c.ii.
\n
\n

0.511 (km)      A1

\n

[1 mark]

\n
c.iii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
", "question_id": "18M.2.AHL.TZ1.H_11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

Consider two events \nA\n and \nA\n defined in the same sample space.

\n
\n

Given that \n\nP\n\n(\nA\n\nB\n)\n=\n\n4\n9\n\n,\n\n P\n\n(\nB\n\n|\n\nA\n)\n=\n\n1\n3\n\n and \n\nP\n\n(\nB\n\n|\n\n\nA\n\n\n)\n=\n\n1\n6\n\n,

\n
\n

Show that P ( A B ) = P ( A ) + P ( A B ) .

\n
[3]
\n
a.
\n
\n

(i)     show that \n\nP\n\n(\nA\n)\n=\n\n1\n3\n\n;

\n

(ii)     hence find \n\nP\n\n(\nB\n)\n.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1

\n

P ( A B ) = P ( A ) + P ( B ) P ( A B )    M1

\n

= P ( A ) + P ( A B ) + P ( A B ) P ( A B )    M1A1

\n

= P ( A ) + P ( A B )    AG

\n

METHOD 2

\n

P ( A B ) = P ( A ) + P ( B ) P ( A B )    M1

\n

= P ( A ) + P ( B ) P ( A | B ) × P ( B )    M1

\n

= P ( A ) + ( 1 P ( A | B ) ) × P ( B )

\n

= P ( A ) + P ( A | B ) × P ( B )    A1

\n

= P ( A ) + P ( A B )    AG

\n

[3 marks]

\n
a.
\n
\n

(i)     use \n\nP\n\n(\nA\n\nB\n)\n=\n\nP\n\n(\nA\n)\n+\n\nP\n\n(\n\nA\n\n\n\nB\n)\n and \n\nP\n\n(\n\nA\n\n\n\nB\n)\n=\n\nP\n\n(\nB\n\n|\n\n\nA\n\n\n)\n\nP\n\n(\n\nA\n\n\n)\n     (M1)

\n

\n\n4\n9\n\n=\n\nP\n\n(\nA\n)\n+\n\n1\n6\n\n\n(\n\n1\n\n\nP\n\n(\nA\n)\n\n)\n\n    A1

\n

\n8\n=\n18\n\nP\n\n(\nA\n)\n+\n3\n\n(\n\n1\n\n\nP\n\n(\nA\n)\n\n)\n\n    M1

\n

\n\nP\n\n(\nA\n)\n=\n\n1\n3\n\n    AG

\n

(ii)     METHOD 1

\n

\n\nP\n\n(\nB\n)\n=\n\nP\n\n(\nA\n\nB\n)\n+\n\nP\n\n(\n\nA\n\n\n\nB\n)\n    M1

\n

\n=\n\nP\n\n(\nB\n\n|\n\nA\n)\n\nP\n\n(\nA\n)\n+\n\nP\n\n(\nB\n\n|\n\n\nA\n\n\n)\n\nP\n\n(\n\nA\n\n\n)\n    M1

\n

\n=\n\n1\n3\n\n×\n\n1\n3\n\n+\n\n1\n6\n\n×\n\n2\n3\n\n=\n\n2\n9\n\n    A1

\n

METHOD 2

\n

\n\nP\n\n(\nA\n\nB\n)\n=\n\nP\n\n(\nB\n\n|\n\nA\n)\n\nP\n\n(\nA\n)\n\n\nP\n\n(\nA\n\nB\n)\n=\n\n1\n3\n\n×\n\n1\n3\n\n=\n\n1\n9\n\n    M1

\n

\n\nP\n\n(\nB\n)\n=\n\nP\n\n(\nA\n\nB\n)\n+\n\nP\n\n(\nA\n\nB\n)\n\n\nP\n\n(\nA\n)\n    M1

\n

\n\nP\n\n(\nB\n)\n=\n\n4\n9\n\n+\n\n1\n9\n\n\n\n1\n3\n\n=\n\n2\n9\n\n    A1

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.AHL.TZ0.H_10", "topics": [ "topic-1-number-and-algebra", "topic-4-statistics-and-probability" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series", "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A café serves sandwiches and cakes. Each customer will choose one of the following three options; buy only a sandwich, buy only a cake or buy both a sandwich and a cake.

\n

The probability that a customer buys a sandwich is 0.72 and the probability that a customer buys a cake is 0.45.

\n
\n

Find the probability that a customer chosen at random will buy

\n
\n

On a typical day 200 customers come to the café.

\n
\n

It is known that 46 % of the customers who come to the café are male, and that 80 % of these buy a sandwich.

\n
\n

both a sandwich and a cake.

\n
[3]
\n
a.i.
\n
\n

only a sandwich.

\n
[1]
\n
a.ii.
\n
\n

Find the expected number of cakes sold on a typical day.

\n
[1]
\n
b.i.
\n
\n

Find the probability that more than 100 cakes will be sold on a typical day.

\n
[3]
\n
b.ii.
\n
\n

A customer is selected at random. Find the probability that the customer is male and buys a sandwich.

\n
[1]
\n
c.i.
\n
\n

A female customer is selected at random. Find the probability that she buys a sandwich.

\n
[4]
\n
c.ii.
\n
", "Markscheme": "
\n

use of formula or Venn diagram       (M1)

\n

0.72 + 0.45 − 1       (A1)

\n

= 0.17       A1

\n

[3 marks]

\n
a.i.
\n
\n

0.72 − 0.17 = 0.55      A1

\n

[1 mark]

\n
a.ii.
\n
\n

200 × 0.45 = 90      A1

\n

[1 mark]

\n
b.i.
\n
\n

let X be the number of customers who order cake

\n

X ~ B(200,0.45)        (M1)

\n

P(X > 100) = P(X ≥ 101)(= 1 − P(X ≤ 100))    (M1)

\n

= 0.0681      A1

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

0.46 × 0.8 = 0.368    A1

\n

[1 mark]

\n
c.i.
\n
\n

METHOD 1

\n

0.368 + 0.54 × P ( S | F ) = 0.72        M1A1A1 

\n

Note: Award M1 for an appropriate tree diagram. Award M1 for LHS, M1 for RHS.

\n

P ( S | F ) = 0.652      A1  

\n

 

\n

METHOD 2

\n

P ( S | F ) = P ( S F ) P ( F )        (M1)

\n

= 0.72 0.368 0.54        A1A1

\n

Note: Award A1 for numerator, A1 for denominator.

\n

P ( S | F ) = 0.652      A1 

\n

 

\n

[4 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "19M.2.AHL.TZ1.H_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

In an arithmetic sequence, the first term is 3 and the second term is 7.

\n
\n

Find the common difference.

\n
[2]
\n
a.
\n
\n

Find the tenth term.

\n
[2]
\n
b.
\n
\n

Find the sum of the first ten terms of the sequence.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to subtract terms     (M1)

\n

eg\n\n\n\n\n\n\nd\n=\n\n\nu\n2\n\n\n\n\n\nu\n1\n\n\n,\n\n \n\n7\n\n3\n

\n

\nd\n=\n4\n     A1     N2

\n

[2 marks]

\n
a.
\n
\n

correct approach     (A1)

\n

eg\n\n\n\n\n\n\n\n\nu\n\n10\n\n\n\n=\n3\n+\n9\n(\n4\n)\n

\n

\n\n\nu\n\n10\n\n\n\n=\n39\n     A1     N2

\n

[2 marks]

\n
b.
\n
\n

correct substitution into sum     (A1)

\n

eg\n\n\n\n\n\n\n\n\nS\n\n10\n\n\n\n=\n5\n(\n3\n+\n39\n)\n,\n\n \n\n\n\nS\n\n10\n\n\n\n=\n\n\n10\n\n2\n\n(\n2\n×\n3\n+\n9\n×\n4\n)\n

\n

\n\n\nS\n\n10\n\n\n\n=\n210\n     A1     N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.S_1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n\ne\n\n\n2\n\n\nsin\n\n\n(\n\n\n\nπ\nx\n\n2\n\n\n)\n\n\n\n\n, for x > 0.

\n

The k th maximum point on the graph of f has x-coordinate xk where \nk\n\n\n\n\nZ\n\n+\n\n\n.

\n
\n

Given that xk + 1 = xk + a, find a.

\n
[4]
\n
a.
\n
\n

Hence find the value of n such that  k = 1 n x k = 861 .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

valid approach to find maxima     (M1)

\n

eg  one correct value of xk, sketch of f

\n

any two correct consecutive values of xk      (A1)(A1)

\n

eg  x1 = 1, x2 = 5

\n

a = 4      A1 N3

\n

[4 marks]

\n
a.
\n
\n

recognizing the sequence x1,  x2,  x3, …, xn is arithmetic  (M1)

\n

eg  d = 4

\n

correct expression for sum       (A1)

\n

eg   n 2 ( 2 ( 1 ) + 4 ( n 1 ) )

\n

valid attempt to solve for n      (M1)

\n

eg  graph, 2n2n − 861 = 0

\n

n = 21       A1 N2

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.SL.TZ1.S_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Consider the differential equation \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n+\n\n(\n\n\n\n2\nx\n\n\n1\n+\n\n\nx\n2\n\n\n\n\n\n)\n\ny\n=\n\n\nx\n2\n\n\n, given that \ny\n=\n2\n when \nx\n=\n0\n.

\n
\n

Show that \n1\n+\n\n\nx\n2\n\n\n is an integrating factor for this differential equation.

\n
[5]
\n
a.
\n
\n

Hence solve this differential equation. Give the answer in the form \ny\n=\nf\n(\nx\n)\n.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

attempting to find an integrating factor     (M1)

\n

\n\n\n\n\n2\nx\n\n\n1\n+\n\n\nx\n2\n\n\n\n\n\nd\n\nx\n=\nln\n\n(\n1\n+\n\n\nx\n2\n\n\n)\n\n    (M1)A1

\n

IF is \n\n\n\ne\n\n\nln\n\n(\n1\n+\n\n\nx\n2\n\n\n)\n\n\n\n     (M1)A1

\n

\n=\n1\n+\n\n\nx\n2\n\n\n    AG

\n

METHOD 2

\n

multiply by the integrating factor

\n

\n(\n1\n+\n\n\nx\n2\n\n\n)\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n+\n2\nx\ny\n=\n\n\nx\n2\n\n\n(\n1\n+\n\n\nx\n2\n\n\n)\n    M1A1

\n

left hand side is equal to the derivative of \n(\n1\n+\n\n\nx\n2\n\n\n)\ny\n

\n

A3

\n

[5 marks]

\n
a.
\n
\n

\n(\n1\n+\n\n\nx\n2\n\n\n)\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n+\n2\nx\ny\n=\n(\n1\n+\n\n\nx\n2\n\n\n)\n\n\nx\n2\n\n\n    (M1)

\n

\n\n\nd\n\n\n\nd\n\nx\n\n\n\n[\n\n(\n1\n+\n\n\nx\n2\n\n\n)\ny\n\n]\n\n=\n\n\nx\n2\n\n\n+\n\n\nx\n4\n\n\n

\n

\n(\n1\n+\n\n\nx\n2\n\n\n)\ny\n=\n\n(\n\n\n\n\n\nx\n2\n\n\n+\n\n\nx\n4\n\n\n\nd\n\nx\n=\n\n\n)\n\n\n \n\n\n\n\n\nx\n3\n\n\n\n3\n\n+\n\n\n\n\nx\n5\n\n\n\n5\n\n(\n+\nc\n)\n    A1A1

\n

\ny\n=\n\n1\n\n1\n+\n\n\nx\n2\n\n\n\n\n\n(\n\n\n\n\n\nx\n3\n\n\n\n3\n\n+\n\n\n\n\nx\n5\n\n\n\n5\n\n+\nc\n\n)\n\n

\n

\nx\n=\n0\n,\n\n \n\ny\n=\n2\n\nc\n=\n2\n    M1A1

\n

\ny\n=\n\n1\n\n1\n+\n\n\nx\n2\n\n\n\n\n\n(\n\n\n\n\n\nx\n3\n\n\n\n3\n\n+\n\n\n\n\nx\n5\n\n\n\n5\n\n+\n2\n\n)\n\n    A1

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.3.AHL.TZ0.HCA_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

The points A, B, C and D have position vectors a, b, c and d, relative to the origin O.

\n

It is given that \n\n\n\nAB\n\n\n\n\n=\n\n\n\nDC\n\n\n\n\n.

\n
\n

The position vectors \n\n\n\nOA\n\n\n\n\n\n\n\n\nOB\n\n\n\n\n\n\n\n\nOC\n\n\n\n\n and \n\n\n\nOD\n\n\n\n\n are given by

\n

a = i + 2j − 3k

\n

b = 3ij + pk

\n

c = qi + j + 2k

\n

d = −i + rj − 2k

\n

where p , q and r are constants.

\n
\n

The point where the diagonals of ABCD intersect is denoted by M.

\n
\n

The plane \nΠ\n cuts the x, y and z axes at X , Y and Z respectively.

\n
\n

Explain why ABCD is a parallelogram.

\n
[1]
\n
a.i.
\n
\n

Using vector algebra, show that \n\n\n\nAD\n\n\n\n\n=\n\n\n\nBC\n\n\n\n\n.

\n
[3]
\n
a.ii.
\n
\n

Show that p = 1, q = 1 and r = 4.

\n
[5]
\n
b.
\n
\n

Find the area of the parallelogram ABCD.

\n
[4]
\n
c.
\n
\n

Find the vector equation of the straight line passing through M and normal to the plane \nΠ\n containing ABCD.

\n
[4]
\n
d.
\n
\n

Find the Cartesian equation of \nΠ\n.

\n
[3]
\n
e.
\n
\n

Find the coordinates of X, Y and Z.

\n
[2]
\n
f.i.
\n
\n

Find YZ.

\n
[2]
\n
f.ii.
\n
", "Markscheme": "
\n

a pair of opposite sides have equal length and are parallel      R1

\n

hence ABCD is a parallelogram      AG

\n

[1 mark]

\n
a.i.
\n
\n

attempt to rewrite the given information in vector form       M1

\n

ba = cd      A1

\n

rearranging d − a = c − b       M1

\n

hence  \n\n\n\nAD\n\n\n\n\n=\n\n\n\nBC\n\n\n\n\n     AG

\n

Note: Candidates may correctly answer part i) by answering part ii) correctly and then deducing there
are two pairs of parallel sides.

\n

[3 marks]

\n
a.ii.
\n
\n

EITHER

\n

use of \n\n\n\nAB\n\n\n\n\n=\n\n\n\nDC\n\n\n\n\n     (M1)

\n

\n\n(\n\n\n\n2\n\n\n\n\n\n3\n\n\n\n\np\n+\n3\n\n\n\n)\n\n=\n\n(\n\n\n\nq\n+\n1\n\n\n\n\n1\n\nr\n\n\n\n\n4\n\n\n\n)\n\n       A1A1

\n

OR

\n

use of \n\n\n\nAD\n\n\n\n\n=\n\n\n\nBC\n\n\n\n\n      (M1)

\n

\n\n(\n\n\n\n\n2\n\n\n\n\nr\n\n2\n\n\n\n\n1\n\n\n\n)\n\n=\n\n(\n\n\n\nq\n\n3\n\n\n\n\n2\n\n\n\n\n2\n\np\n\n\n\n)\n\n      A1A1

\n

THEN

\n

attempt to compare coefficients of i, j, and k in their equation or statement to that effect       M1

\n

clear demonstration that the given values satisfy their equation       A1
p = 1, q = 1, r = 4       AG

\n

[5 marks]

\n
b.
\n
\n

attempt at computing \n\n\n\nAB\n\n\n\n\n\n×\n\n\n\nAD\n\n\n\n\n (or equivalent)       M1

\n

\n\n(\n\n\n\n\n11\n\n\n\n\n\n10\n\n\n\n\n\n2\n\n\n\n)\n\n     A1

\n

area \n=\n\n|\n\n\n\n\nAB\n\n\n\n\n\n×\n\n\n\nAD\n\n\n\n\n\n|\n\n\n(\n\n=\n\n225\n\n\n)\n\n      (M1)

\n

= 15       A1

\n

[4 marks]

\n
c.
\n
\n

valid attempt to find \n\n\n\nOM\n\n\n\n\n=\n\n(\n\n\n1\n2\n\n\n(\n\na\n+\nc\n\n)\n\n\n)\n\n      (M1)

\n

\n\n(\n\n\n\n1\n\n\n\n\n\n3\n2\n\n\n\n\n\n\n\n1\n2\n\n\n\n\n)\n\n     A1

\n

the equation is

\n

r\n\n(\n\n\n\n1\n\n\n\n\n\n3\n2\n\n\n\n\n\n\n\n1\n2\n\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n11\n\n\n\n\n10\n\n\n\n\n2\n\n\n\n)\n\n or equivalent       M1A1

\n

Note: Award maximum M1A0 if 'r = …' (or equivalent) is not seen.

\n

[4 marks]

\n
d.
\n
\n

attempt to obtain the equation of the plane in the form ax + by + cz = d       M1

\n

11x + 10y + 2z = 25      A1A1

\n

Note: A1 for right hand side, A1 for left hand side.

\n

[3 marks]

\n
e.
\n
\n

putting two coordinates equal to zero       (M1)

\n

\n\nX\n\n\n(\n\n\n\n25\n\n\n11\n\n\n,\n\n0\n,\n\n0\n\n)\n\n,\n\n\n\nY\n\n\n(\n\n0\n,\n\n\n5\n2\n\n,\n\n0\n\n)\n\n,\n\n\n\nZ\n\n\n(\n\n0\n,\n\n0\n,\n\n\n\n25\n\n2\n\n\n)\n\n      A1

\n

[2 marks]

\n
f.i.
\n
\n

\n\nYZ\n\n=\n\n\n\n\n\n(\n\n\n5\n2\n\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n\n25\n\n2\n\n\n)\n\n\n2\n\n\n\n     M1

\n

\n=\n\n\n\n325\n\n2\n\n\n\n(\n\n=\n\n\n5\n\n104\n\n\n4\n\n=\n\n\n5\n\n26\n\n\n2\n\n\n)\n\n     A1

\n

[4 marks]

\n
f.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
", "question_id": "18M.1.AHL.TZ2.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

A simple model to predict the population of the world is set up as follows. At time \nt\n years the population of the world is \nx\n, which can be assumed to be a continuous variable. The rate of increase of \nx\n due to births is 0.056\nx\n and the rate of decrease of \nx\n due to deaths is 0.035\nx\n.

\n
\n

Show that \n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n=\n0.021\nx\n.

\n
[1]
\n
a.
\n
\n

Find a prediction for the number of years it will take for the population of the world to double.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n=\n0.056\nx\n\n0.035\nx\n       A1

\n

\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n=\n0.021\nx\n      AG

\n

[1 mark]

\n
a.
\n
\n

METHOD 1

\n

\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n=\n0.021\nx\n

\n

attempt to separate variables       M1

\n

\n\n\n\n1\nx\n\n\n\nd\n\nx\n=\n\n\n0.021\n\n\n\nd\n\nt\n      A1

\n

\n\nln\n\n\nx\n=\n0.021\nt\n(\n+\nc\n)\n      A1

\n

EITHER

\n

\nx\n=\nA\n\n\n\ne\n\n\n0.021\nt\n\n\n\n

\n

\n\n2\nA\n=\nA\n\n\n\ne\n\n\n0.021\nt\n\n\n\n      A1

\n

Note: This A1 is independent of the following marks.

\n

OR

\n

\nt\n=\n0\n\n,\n\n\n\nx\n=\n\n\nx\n0\n\n\n\nc\n=\n\nln\n\n\n\n\nx\n0\n\n\n

\n

\n\n\nln\n\n\n2\n\n\nx\n0\n\n\n=\n0.021\nt\n+\n\nln\n\n\n\n\nx\n0\n\n\n      A1

\n

Note: This A1 is independent of the following marks.

\n

THEN

\n

\n\n\nln\n\n\n2\n=\n0.021\nt\n       (M1)

\n

\n\nt\n=\n33\n years      A1

\n

Note: If a candidate writes \nt\n=\n33.007\n, so \nt\n=\n34\n then award the final A1.

\n

 

\n

METHOD 2

\n

\n\n\n\nd\n\nx\n\n\n\nd\n\nt\n\n\n=\n0.021\nx\n

\n

attempt to separate variables      M1

\n

\n\n\nA\n\n2\nA\n\n\n\n\n1\nx\n\n\nd\n\nx\n=\n\n\n0\nt\n\n\n0.021\n\n\nd\n\nu\n\n\n      A1A1

\n

Note: Award A1 for correct integrals and A1 for correct limits seen anywhere. Do not penalize use of \nt\n in place of \nu\n.

\n

\n\n\n[\n\n\nln\n\n\nx\n\n]\n\nA\n\n2\nA\n\n\n=\n\n\n[\n\n0.021\nu\n\n]\n\n0\nt\n\n      A1

\n

\n\n\nln\n\n\n2\n=\n0.021\nt\n       (M1)

\n

\n\nt\n=\n33\n      A1

\n

 

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.3.AHL.TZ0.HCA_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

The first term of an infinite geometric sequence is 4. The sum of the infinite sequence is 200.

\n
\n

Find the common ratio.

\n
[2]
\n
a.
\n
\n

Find the sum of the first 8 terms.

\n
[2]
\n
b.
\n
\n

Find the least value of n for which Sn > 163.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct substitution into infinite sum      (A1)
eg   200 = 4 1 r

\n

= 0.98 (exact)     A1 N2

\n

[2 marks]

\n
a.
\n
\n

correct substitution     (A1)

\n

4 ( 1 0.98 8 ) 1 0.98

\n

29.8473

\n

29.8    A1 N2

\n

[2 marks]

\n
b.
\n
\n

attempt to set up inequality (accept equation)      (M1)
eg   4 ( 1 0.98 n ) 1 0.98 > 163 , 4 ( 1 0.98 n ) 1 0.98 = 163

\n

correct inequality for n (accept equation) or crossover values      (A1)
eg  n > 83.5234, n = 83.5234, S83 = 162.606 and S84 = 163.354

\n

n = 84     A1 N1

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.SL.TZ2.S_4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

The continuous random variable X has a probability density function given by

\n

\nf\n(\nx\n)\n=\n\n{\n\n\n\n\n\nk\nsin\n\n\n(\n\n\n\nπ\nx\n\n6\n\n\n)\n\n,\n\n\n\n\n0\n\nx\n\n\n6\n\n\n\n\n\n\n0\n,\n\n\n\n\n\notherwise\n\n\n\n\n\n\n\n\n.

\n
\n

Find the value of k .

\n
[4]
\n
a.
\n
\n

By considering the graph of f write down the mean of X ;

\n
[1]
\n
b.i.
\n
\n

By considering the graph of f write down the median of X ;

\n
[1]
\n
b.ii.
\n
\n

By considering the graph of f write down the mode of X .

\n
[1]
\n
b.iii.
\n
\n

Show that P ( 0 X 2 ) = 1 4 .

\n
[4]
\n
c.i.
\n
\n

Hence state the interquartile range of X .

\n
[2]
\n
c.ii.
\n
\n

Calculate P ( X 4 | X 3 ) .

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to equate integral to 1 (may appear later)     M1

\n

k 0 6 sin ( π x 6 ) d x = 1

\n

correct integral     A1

\n

k [ 6 π cos ( π x 6 ) ] 0 6 = 1

\n

substituting limits     M1

\n

6 π ( 1 1 ) = 1 k

\n

k = π 12 A1

\n

[4 marks]

\n
a.
\n
\n

mean = 3     A1

\n

 

\n

Note:     Award A1A0A0 for three equal answers in ( 0 ,   6 ) .

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

median = 3     A1

\n

 

\n

Note:     Award A1A0A0 for three equal answers in ( 0 ,   6 ) .

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

mode = 3     A1

\n

 

\n

Note:     Award A1A0A0 for three equal answers in ( 0 ,   6 ) .

\n

 

\n

[1 mark]

\n
b.iii.
\n
\n

π 12 0 2 sin ( π x 6 ) d x     M1

\n

= π 12 [ 6 π cos ( π x 6 ) ] 0 2      A1

\n

 

\n

Note:     Accept without the π 12 at this stage if it is added later.

\n

 

\n

π 12 [ 6 π ( cos π 3 1 ) ]      M1

\n

= 1 4      AG

\n

[4 marks]

\n
c.i.
\n
\n

from (c)(i) Q 1 = 2      (A1)

\n

as the graph is symmetrical about the middle value x = 3 Q 3 = 4      (A1)

\n

so interquartile range is

\n

4 2

\n

= 2      A1

\n

[3 marks]

\n
c.ii.
\n
\n

P ( X 4 | X 3 ) = P ( 3 X 4 ) P ( X 3 )

\n

= 1 4 1 2      (M1)

\n

= 1 2      A1

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.1.AHL.TZ1.H_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Consider the differential equation \n2\nx\ny\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\ny\n2\n\n\n\n\n\nx\n2\n\n\n, where \nx\n>\n0\n.

\n
\n

Solve the differential equation and show that a general solution is \n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n=\nc\nx\n where \nc\n is a positive constant.

\n
[11]
\n
a.
\n
\n

Prove that there are two horizontal tangents to the general solution curve and state their equations, in terms of \nc\n.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n\n\ny\n2\n\n\n\n\n\nx\n2\n\n\n\n\n2\nx\ny\n\n\n

\n

let \ny\n=\nv\nx\n         M1

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n      (A1)

\n

\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\n\n\n\nv\n2\n\n\n\n\nx\n2\n\n\n\n\n\nx\n2\n\n\n\n\n2\nv\n\n\nx\n2\n\n\n\n\n      (M1)

\n

\nv\n+\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\n\n\n\nv\n2\n\n\n\n1\n\n\n2\nv\n\n\n\n\n\n\n\n(\n\n=\n\nv\n2\n\n\n\n1\n\n2\nv\n\n\n\n)\n\n      (A1)

\n

Note: Or equivalent attempt at simplification.

\n

\nx\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\n\n\n\n\nv\n2\n\n\n\n1\n\n\n2\nv\n\n\n\n\n\n\n\n\n(\n\n=\n\n\nv\n2\n\n\n\n1\n\n2\nv\n\n\n\n)\n\n      A1

\n

\n\n\n2\nv\n\n\n1\n+\n\n\nv\n2\n\n\n\n\n\n\n\nd\n\nv\n\n\n\nd\n\nx\n\n\n=\n\n\n1\nx\n\n      (M1)

\n

\n\n\n\n\n2\nv\n\n\n1\n+\n\n\nv\n2\n\n\n\n\n\n\nd\n\nv\n=\n\n\n\n\n1\nx\n\n\n\nd\n\nx\n      (A1)

\n

\n\nln\n\n\n(\n\n1\n+\n\n\nv\n2\n\n\n\n)\n\n=\n\n\nln\n\n\nx\n+\n\nln\n\n\nc\n       A1A1

\n

Note: Award A1 for LHS and A1 for RHS and a constant.

\n

\n\nln\n\n\n(\n\n1\n+\n\n\n\n\n(\n\n\ny\nx\n\n\n)\n\n\n2\n\n\n\n)\n\n=\n\n\nln\n\n\nx\n+\n\nln\n\n\nc\n         M1

\n

Note: Award M1 for substituting \nv\n=\n\ny\nx\n\n. May be seen at a later stage.

\n

\n1\n+\n\n\n\n(\n\n\ny\nx\n\n\n)\n\n2\n\n\n=\n\nc\nx\n\n       A1

\n

Note: Award A1 for any correct equivalent equation without logarithms.

\n

\n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n=\nc\nx\n     AG

\n

[11 marks]

\n
a.
\n
\n

METHOD 1

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n\n\n\n\ny\n2\n\n\n\n\n\nx\n2\n\n\n\n\n2\nx\ny\n\n\n

\n

(for horizontal tangents) \n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n         M1

\n

\n\n(\n\n\n\n\ny\n2\n\n\n=\n\n\nx\n2\n\n\n\n)\n\n\ny\n=\n±\nx\n

\n

EITHER

\n

using \n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n=\nc\nx\n\n2\n\n\nx\n2\n\n\n=\nc\nx\n         M1

\n

\n2\n\n\nx\n2\n\n\n\nc\nx\n=\n0\n\nx\n=\n\nc\n2\n\n      A1

\n

Note: Award M1A1 for \n2\n\n\ny\n2\n\n\n=\n±\nc\ny\n.

\n

OR

\n

using implicit differentiation of \n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n=\nc\nx\n

\n

\n2\nx\n+\n2\ny\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\nc\n         M1

\n

Note: Accept differentiation of \ny\n=\n\nc\nx\n\n\n\nx\n2\n\n\n\n.

\n

\n\n\n\nd\n\ny\n\n\n\nd\n\nx\n\n\n=\n0\n\nx\n=\n\nc\n2\n\n      A1

\n

THEN

\n

tangents at \ny\n=\n\nc\n2\n\n,\n\n\ny\n=\n\n\nc\n2\n\n       A1A1

\n

hence there are two tangents     AG

\n

 

\n

METHOD 2

\n

\n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n=\nc\nx\n

\n

\n\n\n\n(\n\nx\n\n\nc\n2\n\n\n)\n\n2\n\n\n+\n\n\ny\n2\n\n\n=\n\n\n\n\nc\n2\n\n\n\n4\n\n       M1A1

\n

this is a circle radius \n\n\nc\n2\n\n\n centre \n\n(\n\n\nc\n2\n\n,\n\n\n0\n\n)\n\n       A1

\n

hence there are two tangents     AG

\n

tangents at \ny\n=\n\nc\n2\n\n,\n\n\ny\n=\n\n\nc\n2\n\n       A1A1

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.3.AHL.TZ0.HCA_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

The mean number of squirrels in a certain area is known to be 3.2 squirrels per hectare of woodland. Within this area, there is a 56 hectare woodland nature reserve. It is known that there are currently at least 168 squirrels in this reserve.

\n

Assuming the population of squirrels follow a Poisson distribution, calculate the probability that there are more than 190 squirrels in the reserve.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

X is number of squirrels in reserve
X ∼ Po(179.2)      A1

\n

Note: Award A1 if 179.2 or 56 × 3.2 seen or implicit in future calculations.

\n

recognising conditional probability     M1

\n

P(X > 190 | X ≥ 168)

\n

\n=\n\n\n\nP\n\n\n(\n\nX\n>\n190\n\n)\n\n\n\n\nP\n\n\n(\n\nX\n\n168\n\n)\n\n\n\n=\n\n(\n\n\n\n0.19827\n\n\n\n0.80817\n\n\n\n\n)\n\n       (A1)(A1)

\n

= 0.245      A1

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.AHL.TZ1.H_6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Use l’Hôpital’s rule to determine the value of

\n

\n\n\nlim\n\n\nx\n\n0\n\n\n\n\n\n\n\n\nsin\n\n2\n\n\nx\n\n\nx\nln\n\n(\n1\n+\nx\n)\n\n\n.\n

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to use l’Hôpital’s rule,     M1

\n

\n\nlimit\n\n=\n\n\nlim\n\n\nx\n\n0\n\n\n\n\n\n2\nsin\n\nx\ncos\n\nx\n\n\nln\n\n(\n1\n+\nx\n)\n+\n\nx\n\n1\n+\nx\n\n\n\n\n\n\n\n\nor\n\n\n\n\n\n\nsin\n\n2\nx\n\n\nln\n\n(\n1\n+\nx\n)\n+\n\nx\n\n1\n+\nx\n\n\n\n\n     A1A1

\n

 

\n

Note:     Award A1 for numerator A1 for denominator.

\n

 

\n

this gives 0/0 so use the rule again     (M1)

\n

\n=\n\n\nlim\n\n\nx\n\n0\n\n\n\n\n\n2\n\n\n\ncos\n\n2\n\n\nx\n\n2\n\n\n\nsin\n\n2\n\n\nx\n\n\n\n1\n\n1\n+\nx\n\n\n+\n\n\n1\n+\nx\n\nx\n\n\n\n\n\n(\n1\n+\nx\n)\n\n2\n\n\n\n\n\n\n\n\n\n\nor\n\n\n\n\n\n\n2\ncos\n\n2\nx\n\n\n\n\n2\n+\nx\n\n\n\n\n\n(\n1\n+\nx\n)\n\n2\n\n\n\n\n\n\n     A1A1

\n

 

\n

Note:     Award A1 for numerator A1 for denominator.

\n

 

\n

\n=\n1\n     A1

\n

 

\n

Note:     This A1 is dependent on all previous marks being awarded, except when the first application of L’Hopital’s does not lead to 0/0, when it should be awarded for the correct limit of their derived function.

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.3.AHL.TZ0.HCA_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Use L’Hôpital’s rule to determine the value of

\n

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n\n\n\n2\n\n\n\n+\n3\n\n\ncos\n\n\n(\n\n2\nx\n\n)\n\n\n4\n\n\n3\n\n\nx\n2\n\n\n\n\n\n)\n\n

\n
[5]
\n
a.
\n
\n

Hence find \n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n\n0\nx\n\n\n\n(\n\n\n\n\n\ne\n\n\n\n3\nt\n\n\n\n\n\n\n2\n\n\n\n+\n3\n\n\ncos\n\n\n(\n\n2\nt\n\n)\n\n\n4\n\n)\n\n\n\n\nd\n\nt\n\n\n\n\n0\nx\n\n\n3\n\n\nt\n2\n\n\n\n\n\nd\n\nt\n\n\n\n)\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n\n\n\n2\n\n\n\n+\n3\n\n\ncos\n\n\n2\nx\n\n4\n\n\n3\n\n\nx\n2\n\n\n\n\n=\n\n(\n\n\n\n\n0\n\n\n\n\n0\n\n\n\n\n)\n\n

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\n\n\n6\n\nx\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n\n\n\n2\n\n\n\n\n6\n\n\nsin\n\n\n2\nx\n\n\n6\nx\n\n\n=\n\n(\n\n\n\n\n0\n\n\n\n\n0\n\n\n\n\n)\n\n       M1A1A1

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\n\n\n6\n\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n\n\n\n2\n\n\n\n+\n36\n\n\nx\n2\n\n\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n\n\n\n2\n\n\n\n\n12\n\n\ncos\n\n\n2\nx\n\n6\n\n      A1

\n

= −3       A1

\n

 

\n

[5 marks]

\n
a.
\n
\n

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n\n0\nx\n\n\n\n(\n\n\n\n\n\ne\n\n\n\n3\nt\n\n\n\n\n\n\n2\n\n\n\n+\n3\n\n\ncos\n\n\n2\nt\n\n4\n\n)\n\n\n\n\nd\n\nt\n\n\n\n\n0\nx\n\n\n3\n\n\nt\n2\n\n\n\n\n\nd\n\nt\n\n\n\n)\n\n is of the form \n\n0\n0\n\n

\n

applying l’Hôpital´s rule        (M1)

\n

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n\n\n\n2\n\n\n\n+\n3\n\n\ncos\n\n\n2\nx\n\n4\n\n\n3\n\n\nx\n2\n\n\n\n\n       (A1)

\n

= −3        A1 

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.3.AHL.TZ0.HCA_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Using L’Hôpital’s rule, find \n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\ntan\n\n\n3\nx\n\n3\n\n\ntan\n\n\nx\n\n\n\nsin\n\n\n3\nx\n\n3\n\n\nsin\n\n\nx\n\n\n\n)\n\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\ntan\n\n\n3\nx\n\n3\n\n\ntan\n\n\nx\n\n\n\nsin\n\n\n3\nx\n\n3\n\n\nsin\n\n\nx\n\n\n\n)\n\n

\n

\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n3\n\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\n3\nx\n\n3\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\nx\n\n\n\n3\n\n\n\ncos\n\n\n3\nx\n\n3\n\n\ncos\n\n\nx\n\n\n\n)\n\n\n\n\n\n\n\n(\n\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\n3\nx\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\nx\n\n\n\ncos\n\n\n3\nx\n\n\ncos\n\n\nx\n\n\n\n)\n\n\n\n)\n\n      M1A1A1

\n

Note: Award M1 for attempt at differentiation using l'Hopital's rule, A1 for numerator, A1 for denominator.

\n

 

\n

METHOD 1

\n

using l’Hopital’s rule again

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n18\n\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\n3\nx\n\n\ntan\n\n\n3\nx\n\n6\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\nx\n\n\ntan\n\n\nx\n\n\n\n9\n\n\nsin\n\n\n3\nx\n+\n3\n\n\nsin\n\n\nx\n\n\n\n)\n\n\n\n\n(\n\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n6\n\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\n3\nx\n\n\ntan\n\n\n3\nx\n\n2\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\nx\n\n\ntan\n\n\nx\n\n\n\n3\n\n\nsin\n\n\n3\nx\n+\n\nsin\n\n\nx\n\n\n\n)\n\n\n)\n\n      A1A1

\n

EITHER

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n108\n\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\n3\nx\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\n3\nx\n+\n54\n\n\nse\n\n\n\n\nc\n\n4\n\n\n\n3\nx\n\n12\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\nx\n\n\nta\n\n\n\n\nn\n\n2\n\n\n\nx\n\n6\n\n\nse\n\n\n\n\nc\n\n4\n\n\n\nx\n\n\n\n - 27\n\n\n\ncos\n\n\n3\nx\n+\n3\n\n\ncos\n\n\nx\n\n\n\n)\n\n      A1A1

\n

Note: Not all terms in numerator need to be written in final fraction. Award A1 for \n54\n\n\nse\n\n\n\n\nc\n\n4\n\n\n\n3\nx\n+\n\n\n6\n\n\nse\n\n\n\n\nc\n\n4\n\n\n\nx\n\n\n. However, if the terms are written, they
must be correct to award A1.

\n

attempt to substitute \nx\n=\n0\n         M1

\n

\n=\n\n\n48\n\n\n\n24\n\n\n

\n

OR

\n

\n\n\nd\n\n\n\nd\n\nx\n\n\n\n(\n\n\n18\n\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\n3\nx\n\n\ntan\n\n\n3\nx\n\n6\n\n\nse\n\n\n\n\nc\n\n2\n\n\n\nx\n\n\ntan\n\n\nx\n\n)\n\n\n|\n\n\n\n\nx\n=\n0\n\n\n=\n48\n\n\n\n      (M1)A1

\n

\n\n\nd\n\n\n\nd\n\nx\n\n\n\n(\n\n\n9\n\n\nsin\n\n\n3\nx\n+\n3\n\n\nsin\n\n\nx\n\n)\n\n\n|\n\n\n\n\nx\n=\n0\n\n\n=\n\n24\n\n\n\n      A1

\n

THEN

\n

\n\n(\n\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\ntan\n\n\n3\nx\n\n3\n\n\ntan\n\n\nx\n\n\n\nsin\n\n\n3\nx\n\n3\n\n\nsin\n\n\nx\n\n\n\n)\n\n\n)\n\n=\n\n2\n      A1

\n

 

\n

METHOD 2

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\n3\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\n3\nx\n\n\n\n\n3\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\nx\n\n\n\n\n\n3\n\n\n\ncos\n\n\n3\nx\n\n3\n\n\ncos\n\n\nx\n\n\n\n)\n\n      M1

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\nx\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\n3\nx\n\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\n3\nx\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\nx\n\n(\n\n\ncos\n\n\n3\nx\n\n\ncos\n\n\nx\n\n)\n\n\n\n\n)\n\n      A1

\n

\n=\n\n\n\nlim\n\n\n\nx\n\n0\n\n\n\n\n(\n\n\n\n\ncos\n\n\nx\n+\n\ncos\n\n\n3\nx\n\n\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\n3\nx\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\nx\n\n\n\n)\n\n      M1A1

\n

attempt to substitute \nx\n=\n0\n         M1

\n

\n=\n\n2\n\n\n1\n\n\n

\n

\n=\n\n2\n      A1

\n

 

\n

[9 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.3.AHL.TZ0.HCA_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Three points in three-dimensional space have coordinates A(0, 0, 2), B(0, 2, 0) and C(3, 1, 0).

\n
\n

Find the vector \n\n\nAB\n\n\n\n.

\n
[1]
\n
a.i.
\n
\n

Find the vector \n\n\nAC\n\n\n\n.

\n
[1]
\n
a.ii.
\n
\n

Hence or otherwise, find the area of the triangle ABC.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

\n\n\nAB\n\n\n\n=\n\n(\n\n\n\n\n0\n\n\n\n\n2\n\n\n\n\n\n\n2\n\n\n\n\n\n)\n\n      A1

\n

Note: Accept row vectors or equivalent.

\n

[1 mark]

\n
a.i.
\n
\n

\n\n\nAC\n\n\n\n=\n\n(\n\n\n\n\n3\n\n\n\n\n1\n\n\n\n\n\n\n2\n\n\n\n\n\n)\n\n      A1

\n

Note: Accept row vectors or equivalent.

\n

[1 mark]

\n
a.ii.
\n
\n

METHOD 1

\n

attempt at vector product using \n\n\nAB\n\n\n\n and \n\n\nAC\n\n\n\n.      (M1)

\n

±(2i + 6j +6k)      A1

\n

attempt to use area \n=\n\n1\n2\n\n\n|\n\n\n\nAB\n\n\n\n×\n\n\nAC\n\n\n\n\n|\n\n       M1

\n

\n=\n\n\n\n76\n\n\n2\n\n\n\n\n\n(\n\n=\n\n19\n\n\n)\n\n      A1

\n

 

\n

METHOD 2

\n

attempt to use \n\n\nAB\n\n\n\n\n\n\nAC\n\n\n\n=\n\n|\n\n\n\nAB\n\n\n\n\n|\n\n\n|\n\n\n\nAC\n\n\n\n\n|\n\n\ncos\n\n\nθ\n       M1

\n

\n\n(\n\n\n\n\n0\n\n\n\n\n2\n\n\n\n\n\n\n2\n\n\n\n\n\n)\n\n\n\n(\n\n\n\n\n3\n\n\n\n\n1\n\n\n\n\n\n\n2\n\n\n\n\n\n)\n\n=\n\n\n\n0\n2\n\n\n+\n\n\n2\n2\n\n\n+\n\n\n\n\n(\n\n\n2\n\n)\n\n\n2\n\n\n\n\n\n\n3\n2\n\n\n+\n\n\n1\n2\n\n\n+\n\n\n\n\n(\n\n\n2\n\n)\n\n\n2\n\n\n\n\ncos\n\n\nθ\n

\n

\n6\n=\n\n8\n\n\n14\n\n\n\ncos\n\n\nθ\n      A1

\n

\n\ncos\n\n\nθ\n=\n\n6\n\n\n8\n\n\n14\n\n\n\n=\n\n6\n\n\n112\n\n\n\n

\n

attempt to use area \n=\n\n1\n2\n\n\n|\n\n\n\nAB\n\n\n\n×\n\n\nAC\n\n\n\n\n|\n\n\nsin\n\n\nθ\n       M1

\n

\n=\n\n1\n2\n\n\n8\n\n\n14\n\n\n1\n\n\n\n36\n\n\n112\n\n\n\n\n\n(\n\n=\n\n1\n2\n\n\n8\n\n\n14\n\n\n\n\n76\n\n\n112\n\n\n\n\n)\n\n

\n

\n=\n\n\n\n76\n\n\n2\n\n\n\n\n\n(\n\n=\n\n19\n\n\n)\n\n      A1

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.AHL.TZ2.H_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

In an arithmetic sequence, the first term is 8 and the second term is 5.

\n
\n

Find the common difference.

\n
[2]
\n
a.
\n
\n

Find the tenth term.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

subtracting terms     (M1)

\n

eg\n\n\n\n\n\n\n5\n\n8\n,\n\n \n\n\n\nu\n2\n\n\n\n\n\nu\n1\n\n\n

\n

\nd\n=\n\n3\n     A1     N2

\n

[2 marks]

\n
a.
\n
\n

correct substitution into formula     (A1)

\n

eg\n\n\n\n\n\n\n\n\nu\n\n10\n\n\n\n=\n8\n+\n(\n10\n\n1\n)\n(\n\n3\n)\n,\n\n \n\n8\n\n27\n,\n\n \n\n\n3\n(\n10\n)\n+\n11\n

\n

\n\n\nu\n\n10\n\n\n\n=\n\n19\n     A1     N2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.SL.TZ0.S_2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The following diagram shows [CD], with length b  cm , where b > 1 . Squares with side lengths k  cm ,   k 2  cm ,   k 3  cm ,   , where 0 < k < 1 , are drawn along [CD]. This process is carried on indefinitely. The diagram shows the first three squares.

\n

\"N17/5/MATME/SP1/ENG/TZ0/10.b\"

\n

The total sum of the areas of all the squares is 9 16 . Find the value of b .

\n
", "Markscheme": "
\n

recognizing infinite geometric series with squares     (M1)

\n

eg k 2 + k 4 + k 6 + ,   k 2 1 k 2

\n

correct substitution into S = 9 16 (must substitute into formula)     (A2)

\n

eg k 2 1 k 2 = 9 16

\n

correct working     (A1)

\n

eg 16 k 2 = 9 9 k 2 ,   25 k 2 = 9 ,   k 2 = 9 25

\n

k = 3 5 (seen anywhere)     A1

\n

valid approach with segments and CD (may be seen earlier)     (M1)

\n

eg r = k ,   S = b

\n

correct expression for b in terms of k (may be seen earlier)     (A1)

\n

eg b = k 1 k ,   b = n = 1 k n ,   b = k + k 2 + k 3 +

\n

substituting their value of k into their formula for b     (M1)

\n

eg 3 5 1 3 5 ,   ( 3 5 ) ( 2 5 )

\n

b = 3 2     A1     N3

\n

[9 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.SL.TZ0.S_10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

In an arithmetic sequence, u1 = −5 and d = 3.

\n
\n

Find u8.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct working      (A1)

\n

eg   −5 + (8 − 1)(3)

\n

u8 = 16     A1 N2

\n

 

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.1.SL.TZ0.S_3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The first two terms of an infinite geometric sequence are u1 = 18 and u2 = 12sin2 θ , where 0 < θ < 2\nπ\n , and θ\nπ\n.

\n
\n

Find an expression for r in terms of θ.

\n
[2]
\n
a.i.
\n
\n

Find the values of θ which give the greatest value of the sum.

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

valid approach     (M1)

\n

eg    u 2 u 1 , u 1 u 2

\n

r = 12 sin 2 θ 18 ( = 2 sin 2 θ 3 )       A1 N2

\n

[2 marks]

\n
a.i.
\n
\n

 

\n

METHOD 1 (using differentiation)

\n

recognizing  d S d θ = 0 (seen anywhere)       (M1)

\n

finding any correct expression for  d S d θ        (A1)

\n

eg   0 54 × ( 2 sin 2 θ ) ( 2 + cos 2 θ ) 2 , 54 ( 2 + cos 2 θ ) 2 ( 2 sin 2 θ )

\n

correct working       (A1)

\n

eg  sin 2θ = 0

\n

any correct value for sin−1(0) (seen anywhere)       (A1)

\n

eg  0,  π , … , sketch of sine curve with x-intercept(s) marked both correct values for 2θ (ignore additional values)      (A1)

\n

2θ  π , 3 π  (accept values in degrees)

\n

both correct answers  θ = π 2 , 3 π 2       A1 N4

\n

Note: Award A0 if either or both correct answers are given in degrees.
Award A0 if additional values are given.

\n

 

\n

METHOD 2 (using denominator)

\n

recognizing when S is greatest      (M1)

\n

eg 2 + cos 2θ is a minimum, 1−r is smallest
correct working      (A1)

\n

eg  minimum value of 2 + cos 2θ is 1, minimum r 2 3

\n

correct working      (A1)

\n

eg  cos 2 θ = 1 , 2 3 si n 2 θ = 2 3 , si n 2 θ = 1

\n

EITHER (using cos 2θ)

\n

any correct value for cos−1(−1) (seen anywhere)      (A1)

\n

eg   π , 3 π , … (accept values in degrees), sketch of cosine curve with x-intercept(s) marked

\n

both correct values for 2θ  (ignore additional values)      (A1)

\n

2θ  π , 3 π  (accept values in degrees)

\n

OR (using sinθ)

\n

sinθ = ±1     (A1)

\n

sin−1(1) =  π 2  (accept values in degrees) (seen anywhere)      A1

\n

THEN

\n

both correct answers  θ = π 2 , 3 π 2        A1 N4

\n

Note: Award A0 if either or both correct answers are given in degrees.
Award A0 if additional values are given.

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ1.S_10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

ABCD is a parallelogram, where \n\n\nAB\n\n\n\n = –i + 2j + 3k and \n\n\nAD\n\n\n\n = 4ij – 2k.

\n
\n

Find the area of the parallelogram ABCD.

\n
[3]
\n
a.
\n
\n

By using a suitable scalar product of two vectors, determine whether \n\n\nA\n\n\nB\n^\n\n\nC\n\n\n is acute or obtuse.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nAB\n\n\n\n×\n\n\nAD\n\n\n\n=\n\ni \n+\n10\nj – 7k     M1A1

\n

\n\narea\n\n=\n\n|\n\n\n\nAB\n\n\n\n×\n\n\nAD\n\n\n\n\n|\n\n\n = \n\n\n\n\n1\n2\n\n\n+\n\n\n\n10\n\n2\n\n\n+\n\n\n7\n2\n\n\n\n

\n

 \n=\n5\n\n6\n\n\n(\n\n\n150\n\n\n)\n\n     A1

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

\n\n\nAB\n\n\n\n\n\n\nAD\n\n\n\n=\n\n4\n\n2\n\n6\n     M1A1

\n

\n=\n\n12\n

\n

considering the sign of the answer

\n

\n\n\nAB\n\n\n\n\n\n\nAD\n\n\n\n<\n0\n, therefore angle \n\n\nD\n\n\nA\n^\n\n\nB\n\n\n is obtuse     M1

\n

(as it is a parallelogram), \n\n\nA\n\n\nB\n^\n\n\nC\n\n\n is acute     A1

\n

[4 marks]

\n

METHOD 2

\n

\n\n\nBA\n\n\n\n\n\n\nBC\n\n\n\n=\n+\n4\n+\n2\n+\n6\n     M1A1

\n

\n=\n12\n considering the sign of the answer     M1

\n

\n\n\nBA\n\n\n\n\n\n\nBC\n\n\n\n>\n0\n\n\n\nA\n\n\nB\n^\n\n\nC\n\n\n is acute     A1

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.AHL.TZ1.H_5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The first three terms of a geometric sequence are \nln\n\n\n\nx\n\n16\n\n\n\n, \nln\n\n\n\nx\n8\n\n\n, \nln\n\n\n\nx\n4\n\n\n, for \nx\n>\n0\n.

\n
\n

Find the common ratio.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct use log x n = n log x     A1

\n

eg 16 ln x

\n

valid approach to find r     (M1)

\n

eg u n + 1 u n ,   ln x 8 ln x 16 ,   4 ln x 8 ln x ,   ln x 4 = ln x 16 × r 2

\n

r = 1 2     A1     N2

\n

[3 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.SL.TZ1.S_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

Ten students were surveyed about the number of hours, \nx\n, they spent browsing the Internet during week 1 of the school year. The results of the survey are given below.

\n

\n\n\n\ni\n=\n1\n\n\n10\n\n\n\n\n\nx\ni\n\n\n=\n252\n,\n\n \n\nσ\n=\n5\n\n and median\n\n=\n27.\n\n

\n
\n

Find the mean number of hours spent browsing the Internet.

\n
[2]
\n
a.
\n
\n

During week 2, the students worked on a major project and they each spent an additional five hours browsing the Internet. For week 2, write down

\n

(i)     the mean;

\n

(ii)     the standard deviation.

\n
[2]
\n
b.
\n
\n

During week 3 each student spent 5% less time browsing the Internet than during week 1. For week 3, find

\n

(i)     the median;

\n

(ii)     the variance.

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to substitute into formula for mean     (M1)

\n

eg Σ x 10 ,   252 n ,   252 10

\n

mean = 25.2  (hours)      A1     N2

\n

[2 marks]

\n
a.
\n
\n

(i)     mean = 30.2  (hours)      A1 N1

\n

(ii)     σ = 5  (hours)      A1     N1

\n

[2 marks]

\n
b.
\n
\n

(i)     valid approach     (M1)

\n

eg 95%, 5% of 27

\n

correct working     (A1)

\n

eg 0.95 × 27 ,   27 ( 5 %  of  27 )

\n

median = 25.65  (exact),  25.7  (hours)      A1     N2

\n

(ii)     METHOD 1

\n

variance = ( standard deviation ) 2 (seen anywhere)     (A1)

\n

valid attempt to find new standard deviation     (M1)

\n

eg σ n e w = 0.95 × 5 ,   4.75

\n

variance = 22.5625   ( exact ) ,   22.6      A1     N2

\n

METHOD 2

\n

variance = ( standard deviation ) 2 (seen anywhere)     (A1)

\n

valid attempt to find new variance     (M1)

\n

eg 0.95 2   ,   0.9025 × σ 2

\n

new variance = 22.5625   ( exact ) ,   22.6      A1     N2

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.2.SL.TZ0.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

In an arithmetic sequence, \n\n\nu\n1\n\n\n=\n1.3\n\n\n\nu\n2\n\n\n=\n1.4\n and \n\n\nu\nk\n\n\n=\n31.2\n.

\n
\n

Consider the terms, \n\n\nu\nn\n\n\n, of this sequence such that \nn\n\nk\n.

\n

Let \nF\n be the sum of the terms for which \nn\n is not a multiple of 3.

\n
\n

Find the exact value of \n\n\nS\nk\n\n\n.

\n
[2]
\n
b.
\n
\n

Show that \nF\n=\n3240\n.

\n
[5]
\n
c.
\n
\n

An infinite geometric series is given as \n\n\nS\n\n\n\n=\na\n+\n\na\n\n\n2\n\n\n\n+\n\na\n2\n\n+\n\n\na\n\n\n\n\nZ\n\n+\n\n\n.

\n

Find the largest value of \na\n such that \n\n\nS\n\n\n\n<\nF\n.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

correct substitution      (A1)

\n

eg   \n\n\n300\n\n2\n\n\n(\n\n1.3\n+\n31.2\n\n)\n\n\n\n\n300\n\n2\n\n\n[\n\n2\n\n(\n\n1.3\n\n)\n\n+\n\n(\n\n300\n\n1\n\n)\n\n\n(\n\n0.1\n\n)\n\n\n]\n\n\n\n\n300\n\n2\n\n\n[\n\n2.6\n+\n299\n\n(\n\n0.1\n\n)\n\n\n]\n\n 

\n

\n\n\nS\nk\n\n\n=\n4875\n        A1  N2

\n

[2 marks]

\n
b.
\n
\n

recognizing need to find the sequence of multiples of 3 (seen anywhere)       (M1)

\n

eg   first term is \n\n\nu\n3\n\n\n (= 1.5)   (accept notation \n\n\nu\n1\n\n\n=\n1.5\n) ,

\n

\nd\n=\n0.1\n×\n3\n  (= 0.3) , 100 terms (accept \nn\n=\n100\n), last term is 31.2

\n

(accept notation \n\n\nu\n\n100\n\n\n\n=\n31.2\n) ,  \n\n\nu\n3\n\n\n+\n\n\nu\n6\n\n\n+\n\n\nu\n9\n\n\n+\n\n  (accept \nF\n=\n\n\nu\n3\n\n\n+\n\n\nu\n6\n\n\n+\n\n\nu\n9\n\n\n+\n\n)

\n

correct working for sum of sequence where n is a multiple of 3      A2

\n

\n\n\n100\n\n2\n\n\n(\n\n1.5\n+\n31.2\n\n)\n\n ,  \n50\n\n(\n\n2\n×\n1.5\n+\n99\n×\n0.3\n\n)\n\n ,  1635

\n

valid approach (seen anywhere)       (M1)

\n

eg    \n\n\nS\nk\n\n\n\n\n(\n\n\n\nu\n3\n\n\n+\n\n\nu\n6\n\n\n+\n\n\n)\n\n ,  \n\n\nS\nk\n\n\n\n\n\n100\n\n2\n\n\n(\n\n1.5\n+\n31.2\n\n)\n\n\n\n\nS\nk\n\n\n\n (their sum for \n\n(\n\n\n\nu\n3\n\n\n+\n\n\nu\n6\n\n\n+\n\n\n)\n\n)

\n

correct working (seen anywhere)       A1

\n

eg   \n\n\nS\nk\n\n\n\n1635\n , 4875 − 1635

\n

\nF\n=\n3240\n       AG  N0

\n

[5 marks]

\n
c.
\n
\n

attempt to find \nr\n       (M1)

\n

eg    dividing consecutive terms

\n

correct value of \nr\n (seen anywhere, including in formula)

\n

eg   \n\n1\n\n\n2\n\n\n\n ,  0.707106… ,  \n\na\n\n0.293\n\n\n\n

\n

correct working (accept equation)        (A1)

\n

eg   \n\na\n\n1\n\n\n1\n\n\n2\n\n\n\n\n\n<\n3240\n

\n

correct working     A1

\n

 

\n

METHOD 1 (analytical)

\n

eg   \n3240\n×\n\n(\n\n1\n\n\n1\n\n\n2\n\n\n\n\n)\n\n ,  \na\n<\n948.974\n ,  948.974

\n

METHOD 2 (using table, must find both \n\n\nS\n\n\n\n values)

\n

eg   when \na\n=\n948\n ,  \n\n\nS\n\n\n\n=\n3236.67\n\n  AND  when \na\n=\n949\n ,  \n\n\nS\n\n\n\n=\n3240.08\n\n

\n

\na\n=\n948\n       A1  N2

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.2.SL.TZ2.S_10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The first terms of an infinite geometric sequence, \n\n\nu\nn\n\n\n, are 2, 6, 18, 54, …

\n

The first terms of a second infinite geometric sequence, \n\n\nv\nn\n\n\n, are 2, −6, 18, −54, …

\n

The terms of a third sequence, \n\n\nw\nn\n\n\n, are defined as \n\n\nw\nn\n\n\n=\n\n\nu\nn\n\n\n+\n\n\nv\nn\n\n\n.

\n
\n

The finite series, \n\n\n\nk\n=\n1\n\n\n225\n\n\n\n\n\nw\nk\n\n\n\n , can also be written in the form \n\n\n\nk\n=\n0\n\nm\n\n\n4\n\n\nr\nk\n\n\n\n.

\n
\n

Write down the first three non-zero terms of  w n .

\n
[3]
\n
a.
\n
\n

Find the value of  r .

\n
[2]
\n
b.i.
\n
\n

Find the value of \nm\n.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

attempt to add corresponding terms      (M1)

\n

eg    2 + 2 , 6 + ( 6 ) , 2 ( 3 ) n 1 + 2 ( 3 ) n 1

\n

correct value for  w 5         (A1)

\n

eg   324

\n

4, 36, 324 (accept 4 + 36 + 324)      A1 N3

\n

[3 marks]

\n
a.
\n
\n

valid approach     (M1)

\n

eg   4 × r 1 = 36 ,   4 × 9 n 1

\n

r = 9   (accept  k = 0 m 4 × 9 k m  may be incorrect)      A1 N2

\n

[2 marks]

\n
b.i.
\n
\n

recognition that 225 terms of \n\n\nw\nn\n\n\n consists of 113 non-zero terms    (M1)

\n

eg  \n\n\n1\n\n113\n\n\n\n\n\n\n\n0\n\n112\n\n\n\n\n,  113

\n

\nm\n=\n112\n  (accept \n\n\n\nk\n=\n0\n\n1\n\n12\n\n4\n×\n\n\nr\nk\n\n\n\n\nr\n may be incorrect)      A1 N2

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "19M.2.SL.TZ1.S_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The following table shows values of ln x and ln y.

\n

\n

The relationship between ln x and ln y can be modelled by the regression equation ln y = a ln x + b.

\n
\n

Find the value of a and of b.

\n
[3]
\n
a.
\n
\n

Use the regression equation to estimate the value of y when x = 3.57.

\n
[3]
\n
b.
\n
\n

The relationship between x and y can be modelled using the formula y = kxn, where k ≠ 0 , n ≠ 0 , n ≠ 1.

\n

By expressing ln y in terms of ln x, find the value of n and of k.

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach      (M1)

\n

eg  one correct value

\n

−0.453620, 6.14210

\n

a = −0.454, b = 6.14      A1A1 N3

\n

[3 marks]

\n
a.
\n
\n

correct substitution     (A1)

\n

eg   −0.454 ln 3.57 + 6.14

\n

correct working     (A1)

\n

eg  ln y = 5.56484

\n

261.083 (260.409 from 3 sf)

\n

y = 261, (y = 260 from 3sf)       A1 N3

\n

Note: If no working shown, award N1 for 5.56484.
If no working shown, award N2 for ln y = 5.56484.

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

valid approach for expressing ln y in terms of ln x      (M1)

\n

eg  \n\nln\n\n\ny\n=\n\nln\n\n\n\n(\n\nk\n\n\nx\nn\n\n\n\n)\n\n,\n\n\n\nln\n\n\n\n(\n\nk\n\n\nx\nn\n\n\n\n)\n\n=\na\n\n\nln\n\n\nx\n+\nb\n

\n

correct application of addition rule for logs      (A1)

\n

eg  \n\nln\n\n\nk\n+\n\nln\n\n\n\n(\n\n\n\nx\nn\n\n\n\n)\n\n

\n

correct application of exponent rule for logs       A1

\n

eg  \n\nln\n\n\nk\n+\nn\n\n\nln\n\n\nx\n

\n

comparing one term with regression equation (check FT)      (M1)

\n

eg  \nn\n=\na\n,\n\n\nb\n=\n\nln\n\n\nk\n

\n

correct working for k      (A1)

\n

eg  \n\nln\n\n\nk\n=\n6.14210\n,\n\n\n\nk\n=\n\n\ne\n\n6.14210\n\n\n\n

\n

465.030

\n

\nn\n=\n\n0.454\n,\n\n\nk\n=\n465\n (464 from 3sf)     A1A1 N2N2

\n

 

\n

METHOD 2

\n

valid approach      (M1)

\n

eg  \n\n\ne\n\n\nln\n\n\ny\n\n\n\n=\n\n\ne\n\na\n\n\nln\n\n\nx\n+\nb\n\n\n\n

\n

correct use of exponent laws for \n\n\ne\n\na\n\n\nln\n\n\nx\n+\nb\n\n\n\n     (A1)

\n

eg  \n\n\ne\n\na\n\n\nln\n\n\nx\n\n\n\n×\n\n\ne\nb\n\n\n

\n

correct application of exponent rule for \na\n\n\nln\n\n\nx\n     (A1)

\n

eg  \n\nln\n\n\n\n\nx\na\n\n\n

\n

correct equation in y      A1

\n

eg  \ny\n=\n\n\nx\na\n\n\n×\n\n\ne\nb\n\n\n

\n

comparing one term with equation of model (check FT)      (M1)

\n

eg  \nk\n=\n\n\ne\nb\n\n\n,\n\n\nn\n=\na\n

\n

465.030

\n

\nn\n=\n\n0.454\n,\n\n\nk\n=\n465\n (464 from 3sf)     A1A1 N2N2

\n

 

\n

METHOD 3

\n

valid approach for expressing ln y in terms of ln x (seen anywhere)      (M1)

\n

eg  \n\nln\n\n\ny\n=\n\nln\n\n\n\n(\n\nk\n\n\nx\nn\n\n\n\n)\n\n,\n\n\n\nln\n\n\n\n(\n\nk\n\n\nx\nn\n\n\n\n)\n\n=\na\n\n\nln\n\n\nx\n+\nb\n

\n

correct application of exponent rule for logs (seen anywhere)      (A1)

\n

eg  \n\nln\n\n\n\n(\n\n\n\nx\na\n\n\n\n)\n\n+\nb\n

\n

correct working for b (seen anywhere)      (A1)

\n

eg  \nb\n=\n\nln\n\n\n\n(\n\n\n\ne\nb\n\n\n\n)\n\n

\n

correct application of addition rule for logs      A1

\n

eg  \n\nln\n\n\n\n(\n\n\n\ne\nb\n\n\n\n\nx\na\n\n\n\n)\n\n

\n

comparing one term with equation of model (check FT)     (M1)

\n

eg  \nk\n=\n\n\ne\nb\n\n\n,\n\n\nn\n=\na\n

\n

465.030

\n

\nn\n=\n\n0.454\n,\n\n\nk\n=\n465\n (464 from 3sf)     A1A1 N2N2

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.SL.TZ1.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The acute angle between the vectors 3i − 4j − 5k and 5i − 4j + 3k is denoted by θ.

\n

Find cos θ.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

cos θ = \n\n\n\n(\n\n3\ni\n\n4\nj\n\n5\nk\n\n)\n\n\n\n(\n\n5\ni\n\n4\nj\n+\n3\nk\n\n)\n\n\n\n\n|\n\n3\ni\n\n4\nj\n\n5\nk\n\n|\n\n\n|\n\n5\ni\n\n4\nj\n+\n3\nk\n\n|\n\n\n\n      (M1)

\n

\n=\n\n\n16\n\n\n\n50\n\n\n50\n\n\n\n     A1A1

\n

Note: A1 for correct numerator and A1 for correct denominator.

\n

\n=\n\n8\n\n25\n\n\n\n(\n\n=\n\n\n16\n\n\n50\n\n\n=\n0.32\n\n)\n\n      A1

\n

[4 marks]

\n

 

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.AHL.TZ2.H_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The following diagram shows the graph of a function \nf\n, with domain \n\n2\n\nx\n\n4\n.

\n

\"N17/5/MATME/SP1/ENG/TZ0/03\"

\n

The points \n(\n\n2\n,\n\n \n\n0\n)\n and \n(\n4\n,\n\n \n\n7\n)\n lie on the graph of \nf\n.

\n
\n

On the grid, sketch the graph of f 1 .

\n
", "Markscheme": "
\n

\"N17/5/MATME/SP1/ENG/TZ0/03.c/M\"     A1A1A1     N3

\n

 

\n

Notes:     Award A1 for both end points within circles,

\n

A1 for images of ( 2 ,   3 ) and ( 0 ,   2 ) within circles,

\n

A1 for approximately correct reflection in y = x , concave up then concave down shape (do not accept line segments).

\n

 

\n

[3 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.SL.TZ0.S_3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Solve log 2 ( 2 sin x ) + log 2 ( cos x ) = 1 , for 2 π < x < 5 π 2 .

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct application of log a + log b = log a b     (A1)

\n

eg log 2 ( 2 sin x cos x ) ,   log 2 + log ( sin x ) + log ( cos x )

\n

correct equation without logs     A1

\n

eg 2 sin x cos x = 2 1 ,   sin x cos x = 1 4 ,   sin 2 x = 1 2

\n

recognizing double-angle identity (seen anywhere)     A1

\n

eg log ( sin 2 x ) ,   2 sin x cos x = sin 2 x ,   sin 2 x = 1 2

\n

evaluating sin 1 ( 1 2 ) = π 6   ( 30 )     (A1)

\n

correct working     A1

\n

eg x = π 12 + 2 π ,   2 x = 25 π 6 ,   29 π 6 ,   750 ,   870 ,   x = π 12 and x = 5 π 12 , one correct final answer

\n

x = 25 π 12 ,   29 π 12 (do not accept additional values)     A2     N0

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.SL.TZ2.S_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-6-pythagorean-identity-double-angles" ] }, { "Question": "
\n

The points A, B and C have the following position vectors with respect to an origin O.

\n

\n\n\n\nO\nA\n\n\n\n\n=\n2\ni + j – 2k

\n

\n\n\n\nO\nB\n\n\n\n\n=\n2\nij + 2k

\n

\n\n\n\nO\nC\n\n\n\n\n=\n i + 3j + 3k

\n
\n

The plane Π\n\n\n2\n\n contains the points O, A and B and the plane Π\n\n\n3\n\n contains the points O, A and C.

\n
\n

Find the vector equation of the line (BC).

\n
[3]
\n
a.
\n
\n

Determine whether or not the lines (OA) and (BC) intersect.

\n
[6]
\n
b.
\n
\n

Find the Cartesian equation of the plane Π\n\n\n1\n\n, which passes through C and is perpendicular to \n\n\n\nO\nA\n\n\n\n\n.

\n
[3]
\n
c.
\n
\n

Show that the line (BC) lies in the plane Π\n\n\n1\n\n.

\n
[2]
\n
d.
\n
\n

Verify that 2j + k is perpendicular to the plane Π\n\n\n2\n\n.

\n
[3]
\n
e.
\n
\n

Find a vector perpendicular to the plane Π\n\n\n3\n\n.

\n
[1]
\n
f.
\n
\n

Find the acute angle between the planes Π\n\n\n2\n\n and Π\n\n\n3\n\n.

\n
[4]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\nB\nC\n\n\n\n\n = (i + 3j + 3k) \n\n (2i \n\n j + 2k) = \n\ni + 4j + k    (A1)

\n

r = (2i \n\n j + 2k) + \nλ\n(\n\ni + 4j + k)

\n

(or r = (i + 3j + 3k) + \nλ\n(\n\ni + 4j + k)     (M1)A1

\n

 

\n

Note:     Do not award A1 unless r = or equivalent correct notation seen.

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to write in parametric form using two different parameters AND equate     M1

\n

\n2\nμ\n=\n2\n\nλ\n

\n

\nμ\n=\n\n1\n+\n4\nλ\n

\n

\n\n2\nμ\n=\n2\n+\nλ\n     A1

\n

attempt to solve first pair of simultaneous equations for two parameters     M1

\n

solving first two equations gives \nλ\n=\n\n4\n9\n\n,\n\n \n\nμ\n=\n\n7\n9\n\n     (A1)

\n

substitution of these two values in third equation     (M1)

\n

since the values do not fit, the lines do not intersect     R1

\n

 

\n

Note:     Candidates may note that adding the first and third equations immediately leads to a contradiction and hence they can immediately deduce that the lines do not intersect.

\n

 

\n

[6 marks]

\n
b.
\n
\n

METHOD 1

\n

plane is of the form r \n\n (2i + j \n\n 2k) = d     (A1)

\n

d = (i + 3j + 3k) \n\n (2i + j \n\n 2k) = \n\n1     (M1)

\n

hence Cartesian form of plane is \n2\nx\n+\ny\n\n2\nz\n=\n\n1\n     A1

\n

METHOD 2

\n

plane is of the form \n2\nx\n+\ny\n\n2\nz\n=\nd\n     (A1)

\n

substituting \n(\n1\n,\n\n \n\n3\n,\n\n \n\n3\n)\n (to find gives \n2\n+\n3\n\n6\n=\n\n1\n)     (M1)

\n

hence Cartesian form of plane is \n2\nx\n+\ny\n\n2\nz\n=\n\n1\n     A1

\n

[3 marks]

\n
c.
\n
\n

METHOD 1

\n

attempt scalar product of direction vector BC with normal to plane     M1

\n

(\n\ni + 4j + k) \n\n (2i + j \n\n 2k) \n=\n\n2\n+\n4\n\n2\n

\n

\n=\n0\n     A1

\n

hence BC lies in Π\n\n\n1\n\n     AG

\n

METHOD 2

\n

substitute eqn of line into plane     M1

\n

\n\nline \n\nr\n=\n\n(\n\n\n\n\n2\n\n\n\n\n\n\n1\n\n\n\n\n\n2\n\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n\n\n1\n\n\n\n\n\n4\n\n\n\n\n1\n\n\n\n\n)\n\n.\n\n Plane \n\n\n\nπ\n1\n\n\n:\n2\nx\n+\ny\n\n2\nz\n=\n\n1\n

\n

\n2\n(\n2\n\nλ\n)\n+\n(\n\n1\n+\n4\nλ\n)\n\n2\n(\n2\n+\nλ\n)\n

\n

\n=\n\n1\n     A1

\n

hence BC lies in Π\n\n\n1\n\n     AG

\n

 

\n

Note:     Candidates may also just substitute \n2\ni\n\nj\n+\n2\nk\n into the plane since they are told C lies on \n\n\nπ\n1\n\n\n.

\n

 

\n

Note:     Do not award A1FT.

\n

 

\n

[2 marks]

\n
d.
\n
\n

METHOD 1

\n

applying scalar product to \n\n\n\nO\nA\n\n\n\n\n and \n\n\n\nO\nB\n\n\n\n\n     M1

\n

(2j + k) \n\n (2i + j \n\n 2k) = 0     A1

\n

(2j + k) \n\n (2i \n\n j + 2k) =0     A1

\n

METHOD 2

\n

attempt to find cross product of \n\n\n\nO\nA\n\n\n\n\n and \n\n\n\nO\nB\n\n\n\n\n     M1

\n

plane Π\n\n\n2\n\n has normal \n\n\nOA\n\n\n\n×\n\n\nOB\n\n\n\n = \n\n 8j \n\n 4k     A1

\n

since \n\n8j \n\n 4k = \n\n4(2j + k), 2j + k is perpendicular to the plane Π\n\n\n2\n\n     R1

\n

[3 marks]

\n
e.
\n
\n

plane Π\n\n\n3\n\n has normal \n\n\nOA\n\n\n\n×\n\n\nOC\n\n\n\n = 9i \n\n 8j + 5k     A1

\n

[1 mark]

\n
f.
\n
\n

attempt to use dot product of normal vectors     (M1)

\n

\ncos\n\nθ\n=\n\n\n(\n2\nj\n+\nk\n)\n\n(\n9\ni\n\n8\nj\n+\n5\nk\n)\n\n\n\n|\n\n2\nj\n+\nk\n\n|\n\n\n|\n\n9\ni\n\n8\nj\n+\n5\nk\n\n|\n\n\n\n     (M1)

\n

\n=\n\n\n\n11\n\n\n\n5\n\n\n170\n\n\n\n\n\n\n(\n=\n\n0.377\n\n)\n     (A1)

\n

 

\n

Note:     Accept \n\n\n11\n\n\n\n5\n\n\n170\n\n\n\n.   acute angle between planes \n=\n\n67.8\n\n\n\n\n\n\n(\n\n=\n\n1.18\n\n\n)\n     A1

\n

 

\n

[4 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "17M.2.AHL.TZ2.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n1\n+\n\n\n\ne\n\n\n\nx\n\n\n\n and \ng\n(\nx\n)\n=\n2\nx\n+\nb\n, for \nx\n\n\nR\n\n, where \nb\n is a constant.

\n
\n

Find ( g f ) ( x ) .

\n
[2]
\n
a.
\n
\n

Given that lim x + ( g f ) ( x ) = 3 , find the value of b .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to form composite     (M1)

\n

eg g ( 1 + e x )

\n

correct function     A1     N2

\n

eg ( g f ) ( x ) = 2 + b + 2 e x ,   2 ( 1 + e x ) + b

\n

[2 marks]

\n
a.
\n
\n

evidence of lim x ( 2 + b + 2 e x ) = 2 + b + lim x ( 2 e x )     (M1)

\n

eg 2 + b + 2 e , graph with horizontal asymptote when x

\n

 

\n

Note:     Award M0 if candidate clearly has incorrect limit, such as x 0 ,   e ,   2 e 0 .

\n

 

\n

evidence that e x 0 (seen anywhere)     (A1)

\n

eg lim x ( e x ) = 0 ,   1 + e x 1 ,   2 ( 1 ) + b = 3 ,   e large negative number 0 , graph of y = e x or

\n

y = 2 e x with asymptote y = 0 , graph of composite function with asymptote y = 3

\n

correct working     (A1)

\n

eg 2 + b = 3

\n

b = 5     A1     N2

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.SL.TZ0.S_5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

Consider a geometric sequence where the first term is 768 and the second term is 576.

\n

Find the least value of n such that the n th term of the sequence is less than 7.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to find r     (M1)

\n

eg 576 768 ,   768 576 ,   0.75

\n

correct expression for u n     (A1)

\n

eg 768 ( 0.75 ) n 1

\n

EITHER (solving inequality)

\n

valid approach (accept equation)     (M1)

\n

eg u n < 7

\n

valid approach to find n     M1

\n

eg 768 ( 0.75 ) n 1 = 7 ,   n 1 > log 0.75 ( 7 768 ) , sketch

\n

correct value

\n

eg n = 17.3301     (A1)

\n

n = 18 (must be an integer)     A1     N2

\n

OR (table of values)

\n

valid approach     (M1)

\n

eg u n > 7 , one correct crossover value

\n

both crossover values, u 17 = 7.69735 and u 18 = 5.77301     A2

\n

n = 18 (must be an integer)     A1     N2

\n

OR (sketch of functions)

\n

valid approach     M1

\n

eg sketch of appropriate functions

\n

valid approach     (M1) 

\n

eg finding intersections or roots (depending on function sketched)

\n

correct value

\n

eg n = 17.3301     (A1)

\n

n = 18 (must be an integer)     A1     N2

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.SL.TZ2.S_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

The following diagram shows the graph of a function \ny\n=\nf\n(\nx\n)\n, for \n\n6\n\nx\n\n\n2\n.

\n

The points \n(\n\n6\n,\n\n \n\n6\n)\n and \n(\n\n2\n,\n\n \n\n6\n)\n lie on the graph of \nf\n. There is a minimum point at \n(\n\n4\n,\n\n \n\n0\n)\n.

\n

\n
\n

Let \ng\n(\nx\n)\n=\nf\n(\nx\n\n5\n)\n.

\n
\n

Write down the range of f .

\n
[2]
\n
a.
\n
\n

Write down the domain of g .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct interval     A2     N2

\n

eg 0 y 6 ,   [ 0 ,   6 ] , from 0 to 6

\n

[2 marks]

\n
a.
\n
\n

correct interval     A2     N2

\n

eg 1 x 3 ,   [ 1 ,   3 ] , from 1 to 3

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.SL.TZ2.S_3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n\n(\n\n\nx\n2\n\n\n+\n3\n\n)\n7\n\n\n. Find the term in \n\n\nx\n5\n\n\n in the expansion of the derivative, \n\nf\n\n\n(\nx\n)\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 

\n

derivative of \nf\n(\nx\n)\n     A2

\n

\n7\n\n(\n\n\nx\n2\n\n\n+\n3\n\n)\n6\n\n\n(\nx\n2\n)\n

\n

recognizing need to find \n\n\nx\n4\n\n\n term in \n\n(\n\n\nx\n2\n\n\n+\n3\n\n)\n6\n\n\n (seen anywhere)     R1

\n

eg\n\n\n\n\n\n\n14\nx\n\n (term in \n\n\n\nx\n4\n\n\n)\n

\n

valid approach to find the terms in \n\n(\n\n\nx\n2\n\n\n+\n3\n\n)\n6\n\n\n     (M1)

\n

eg\n\n\n\n\n\n\n\n(\n\n\n\n\n6\n\n\n\n\nr\n\n\n\n\n)\n\n\n(\n\n\nx\n2\n\n\n\n)\n\n6\n\nr\n\n\n\n\n(\n3\n\n)\nr\n\n\n,\n\n \n\n\n(\n\n\nx\n2\n\n\n\n)\n6\n\n\n\n(\n3\n\n)\n0\n\n\n+\n\n(\n\n\nx\n2\n\n\n\n)\n5\n\n\n\n(\n3\n\n)\n1\n\n\n+\n\n, Pascal’s triangle to 6th row

\n

identifying correct term (may be indicated in expansion)     (A1)

\n

eg\n\n\n\n\n\n\n\n5th term, \n\nr\n=\n2\n,\n\n \n\n\n(\n\n\n\n\n6\n\n\n\n\n4\n\n\n\n\n)\n\n,\n\n \n\n\n(\n\n\nx\n2\n\n\n\n)\n2\n\n\n\n(\n3\n\n)\n4\n\n\n

\n

correct working (may be seen in expansion)     (A1)

\n

eg\n\n\n\n\n\n\n\n(\n\n\n\n\n6\n\n\n\n\n4\n\n\n\n\n)\n\n\n(\n\n\nx\n2\n\n\n\n)\n2\n\n\n\n(\n3\n\n)\n4\n\n\n,\n\n \n\n15\n×\n\n\n3\n4\n\n\n,\n\n \n\n14\nx\n×\n15\n×\n81\n\n(\n\n\nx\n2\n\n\n\n)\n2\n\n\n

\n

\n17010\n\n\nx\n5\n\n\n     A1     N3

\n

METHOD 2

\n

recognition of need to find \n\n\nx\n6\n\n\n in \n\n(\n\n\nx\n2\n\n\n+\n3\n\n)\n7\n\n\n (seen anywhere) R1 

\n

valid approach to find the terms in \n\n(\n\n\nx\n2\n\n\n+\n3\n\n)\n7\n\n\n     (M1)

\n

eg\n\n\n\n\n\n\n\n(\n\n\n\n\n7\n\n\n\n\nr\n\n\n\n\n)\n\n\n(\n\n\nx\n2\n\n\n\n)\n\n7\n\nr\n\n\n\n\n(\n3\n\n)\nr\n\n\n,\n\n \n\n\n(\n\n\nx\n2\n\n\n\n)\n7\n\n\n\n(\n3\n\n)\n0\n\n\n+\n\n(\n\n\nx\n2\n\n\n\n)\n6\n\n\n\n(\n3\n\n)\n1\n\n\n+\n\n, Pascal’s triangle to 7th row

\n

identifying correct term (may be indicated in expansion)     (A1)

\n

eg\n\n\n\n\n\n6th term, \nr\n=\n3\n,\n\n \n\n\n(\n\n\n\n\n7\n\n\n\n\n3\n\n\n\n\n)\n\n,\n\n (\n\n\n\n\nx\n\n2\n\n\n\n\n)\n3\n\n\n\n(\n3\n\n)\n4\n\n\n

\n

correct working (may be seen in expansion)     (A1)

\n

eg\n\n\n\n\n\n\n\n(\n\n\n\n\n7\n\n\n\n\n4\n\n\n\n\n)\n\n\n\n(\n\n\n\n\nx\n\n2\n\n\n\n)\n3\n\n\n\n(\n3\n\n)\n4\n\n\n,\n\n \n\n35\n×\n\n\n3\n4\n\n\n

\n

correct term     (A1)

\n

\n2835\n\n\nx\n6\n\n\n

\n

differentiating their term in \n\n\nx\n6\n\n\n     (M1)

\n

eg\n\n\n\n\n\n\n(\n2835\n\n\nx\n6\n\n\n\n)\n\n\n,\n\n (6)(2835\n\n\n\n\nx\n\n5\n\n\n)\n

\n

\n17010\n\n\nx\n5\n\n\n     A1     N3

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.SL.TZ1.S_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n16\n\nx\n\n. The line \nL\n is tangent to the graph of \nf\n at \nx\n=\n8\n.

\n
\n

\nL\n can be expressed in the form r \n=\n\n(\n\n\n\n\n8\n\n\n\n\n2\n\n\n\n\n)\n\n+\nt\nu.

\n
\n

The direction vector of \ny\n=\nx\n is \n\n(\n\n\n\n\n1\n\n\n\n\n1\n\n\n\n\n)\n\n.

\n
\n

Find the gradient of L .

\n
[2]
\n
a.
\n
\n

Find u.

\n
[2]
\n
b.
\n
\n

Find the acute angle between y = x and L .

\n
[5]
\n
c.
\n
\n

Find  ( f f ) ( x ) .

\n
[3]
\n
d.i.
\n
\n

Hence, write down f 1 ( x ) .

\n
[1]
\n
d.ii.
\n
\n

Hence or otherwise, find the obtuse angle formed by the tangent line to f at x = 8 and the tangent line to f at x = 2 .

\n
[3]
\n
d.iii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to find  f ( 8 )      (M1)

\n

eg   f ( x ) ,   y ,   16 x 2

\n

−0.25 (exact)     A1 N2

\n

[2 marks]

\n
a.
\n
\n

u null  or any scalar multiple    A2 N2

\n

[2 marks]

\n
b.
\n
\n

correct scalar product and magnitudes           (A1)(A1)(A1)

\n

scalar product  = 1 × 4 + 1 × 1 ( = 3 )

\n

magnitudes  = 1 2 + 1 2 ,   4 2 + ( 1 ) 2    ( = 2 , 17 )

\n

substitution of their values into correct formula           (M1)

\n

eg  4 1 1 2 + 1 2 4 2 + ( 1 ) 2 3 2 17 ,  2.1112,  120.96° 

\n

1.03037 ,  59.0362°

\n

angle = 1.03 ,  59.0°    A1 N4

\n

[5 marks]

\n
c.
\n
\n

attempt to form composite  ( f f ) ( x )      (M1)

\n

eg    f ( f ( x ) ) ,   f ( 16 x ) ,   16 f ( x )

\n

correct working     (A1)

\n

eg  16 16 x  ,   16 × x 16

\n

( f f ) ( x ) = x      A1 N2

\n

[3 marks]

\n
d.i.
\n
\n

f 1 ( x ) = 16 x   (accept  y = 16 x , 16 x )    A1 N1

\n

Note: Award A0 in part (ii) if part (i) is incorrect.
Award A0 in part (ii) if the candidate has found f 1 ( x ) = 16 x by interchanging x and y .

\n

[1 mark]

\n
d.ii.
\n
\n

METHOD 1

\n

recognition of symmetry about y = x     (M1)

\n

eg   (2, 8) ⇔ (8, 2) 

\n

evidence of doubling their angle        (M1)

\n

eg    2 × 1.03 ,   2 × 59.0

\n

2.06075, 118.072°

\n

2.06 (radians)  (118 degrees)     A1  N2

\n

 

\n

METHOD 2

\n

finding direction vector for tangent line at x = 2       (A1)

\n

eg    ( 1 4 ) ,   ( 1 4 )

\n

substitution of their values into correct formula (must be from vectors)      (M1)

\n

eg    4 4 1 2 + 4 2 4 2 + ( 1 ) 2 ,   8 17 17

\n

2.06075, 118.072°

\n

2.06 (radians)  (118 degrees)     A1  N2

\n

 

\n

METHOD 3

\n

using trigonometry to find an angle with the horizontal      (M1)

\n

eg    tan θ = 1 4 ,   tan θ = 4

\n

finding both angles of rotation      (A1)

\n

eg    θ 1 = 0.244978 ,  14 .0362 ,   θ 1 = 1.81577 ,  104 .036

\n

2.06075, 118.072°

\n

2.06 (radians)  (118 degrees)     A1  N2

\n

[3 marks]

\n
d.iii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
d.iii.
\n
", "question_id": "19M.2.SL.TZ1.S_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n\n\nx\n2\n\n\n\n1\n and \ng\n(\nx\n)\n=\n\n\nx\n2\n\n\n\n2\n, for \nx\n\n\nR\n\n.

\n
\n

Show that ( f g ) ( x ) = x 4 4 x 2 + 3 .

\n
[2]
\n
a.
\n
\n

On the following grid, sketch the graph of ( f g ) ( x ) , for 0 x 2.25 .

\n

\"M17/5/MATME/SP2/ENG/TZ2/06.b\"

\n
[3]
\n
b.
\n
\n

The equation ( f g ) ( x ) = k has exactly two solutions, for 0 x 2.25 . Find the possible values of k .

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to form composite in either order     (M1)

\n

eg f ( x 2 2 ) ,   ( x 2 1 ) 2 2

\n

( x 4 4 x 2 + 4 ) 1     A1

\n

( f g ) ( x ) = x 4 4 x 2 + 3     AG     N0

\n

[2 marks]

\n
a.
\n
\n

\"M17/5/MATME/SP2/ENG/TZ2/06.b/M\"    A1

\n

A1A1     N3

\n

 

\n

Note:     Award A1 for approximately correct shape which changes from concave down to concave up. Only if this A1 is awarded, award the following:

\n

A1 for left hand endpoint in circle and right hand endpoint in oval,

\n

A1 for minimum in oval.

\n

 

\n

[3 marks]

\n
b.
\n
\n

evidence of identifying max/min as relevant points     (M1)

\n

eg x = 0 ,   1.41421 ,   y = 1 ,   3

\n

correct interval (inclusion/exclusion of endpoints must be correct)     A2     N3

\n

eg 1 < k 3 ,   ] 1 ,  3 ] ,   ( 1 ,   3 ]

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.SL.TZ2.S_6", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\n\n\nx\n2\n\n\n\n4\nx\n+\n5\n.

\n
\n

The function can also be expressed in the form \nf\n(\nx\n)\n=\n\n(\nx\n\nh\n\n)\n2\n\n\n+\nk\n.

\n
\n

(i)     Write down the value of \nh\n.

\n

(ii)     Find the value of \nk\n.

\n
", "Markscheme": "
\n

(i)     \nh\n=\n2\n     A1     N1

\n

(ii)     METHOD 1

\n

valid attempt to find \nk\n     (M1)

\n

eg\n\n\n\n\n\n\nf\n(\n2\n)\n

\n

correct substitution into their function     (A1)

\n

eg\n\n\n\n\n\n\n\n(\n2\n\n)\n2\n\n\n\n4\n(\n2\n)\n+\n5\n

\n

\nk\n=\n1\n     A1     N2

\n

METHOD 2

\n

valid attempt to complete the square     (M1)

\n

eg\n\n\n\n\n\n\n\n\nx\n2\n\n\n\n4\nx\n+\n4\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n(\n\n\nx\n2\n\n\n\n4\nx\n+\n4\n)\n\n4\n+\n5\n,\n\n \n\n\n(\nx\n\n2\n\n)\n2\n\n\n+\n1\n

\n

\nk\n=\n1\n     A1     N2

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.1.SL.TZ0.S_1", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-6-quadratic-function" ] }, { "Question": "
\n

The vectors a and b are defined by \n\n(\n\n\n\n\n1\n\n\n\n\n1\n\n\n\n\nt\n\n\n\n\n)\n\nb \n\n(\n\n\n\n\n0\n\n\n\n\n\n\nt\n\n\n\n\n\n\n4\nt\n\n\n\n\n\n)\n\n, where \nt\n\n\nR\n\n.

\n
\n

Find and simplify an expression for a • b in terms of \nt\n.

\n
[2]
\n
a.
\n
\n

Hence or otherwise, find the values of \nt\n for which the angle between a and b is obtuse .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

a • b = \n\n(\n\n1\n×\n0\n\n)\n\n+\n\n(\n\n1\n×\n\nt\n\n)\n\n+\n\n(\n\nt\n×\n4\nt\n\n)\n\n      (M1)

\n

\n\nt\n+\n4\n\n\nt\n2\n\n\n      A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

recognition that  a • b = |a||b|cos θ      (M1)

\n

a • b < 0 or \n\nt\n+\n4\n\n\nt\n2\n\n\n < 0 or cos θ < 0      R1

\n

Note: Allow ≤ for R1.

\n

 

\n

attempt to solve using sketch or sign diagram      (M1)

\n

\n0\n<\nt\n<\n\n1\n4\n\n      A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.1.AHL.TZ0.H_5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

Mia baked a very large apple pie that she cuts into slices to share with her friends. The smallest slice is cut first. The volume of each successive slice of pie forms a geometric sequence.

\n

The second smallest slice has a volume of 30cm3. The fifth smallest slice has a volume of 240cm3.

\n
\n

Find the common ratio of the sequence.

\n
[2]
\n
a.
\n
\n

Find the volume of the smallest slice of pie.

\n
[2]
\n
b.
\n
\n

The apple pie has a volume of 61425cm3.

\n

Find the total number of slices Mia can cut from this pie.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

u1r=30  and  u1r4=240,       (M1)

\n


Note:
Award (M1) for both the given terms expressed in the formula for un.

\n

OR

30r3=240   r3=8       (M1)

\n


Note:
 Award (M1) for a correct equation seen.

r= 2       (A1)      (C2)

\n


[2 marks]

\n
a.
\n
\n

u1×2=30  OR  u1×24=240       (M1)

\n


Note:
Award (M1) for their correct substitution in geometric sequence formula.

\n


u1= 15       (A1)(ft)      (C2)

\n


Note: Follow through from part (a).

\n


[2 marks]

\n
b.
\n
\n

152n-12-1=61425         (M1)

\n


Note: Award (M1) for correctly substituted geometric series formula equated to 61425.

\n


n= 12  (slices)       (A1)(ft)      (C2)

\n


Note: Follow through from parts (a) and (b).

\n


[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_15", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n8\nx\n\n5\n\n\nc\nx\n+\n6\n\n\n for \nx\n\n\n\n6\nc\n\n,\n\n\nc\n\n0\n.

\n
\n

Write down the equation of the horizontal asymptote to the graph of f.

\n
", "Markscheme": "
\n

valid approach (M1)
eg  \n\n\n\nlim\n\n\nf\n\n\nx\n\n\n\n\n\n\n(\nx\n)\n\n,\n\n\ny\n=\n\n8\nc\n\n

\n

y = −4 (must be an equation)      A1 N2

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.SL.TZ2.S_7", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-8-reciprocal-and-simple-rational-functions-equations-of-asymptotes" ] }, { "Question": "
\n

Olava’s Pizza Company supplies and delivers large cheese pizzas.

\n

The total cost to the customer, C, in Papua New Guinean Kina (PGK), is modelled by the function

\n

Cn=34.50n+8.50, n2, n,

\n

where n, is the number of large cheese pizzas ordered. This total cost includes a fixed cost for delivery.

\n
\n

State, in the context of the question, what the value of 34.50 represents.

\n
[1]
\n
a.i.
\n
\n

State, in the context of the question, what the value of 8.50 represents.

\n
[1]
\n
a.ii.
\n
\n

Write down the minimum number of pizzas that can be ordered.

\n
[1]
\n
b.
\n
\n

Kaelani has 450 PGK.

\n

Find the maximum number of large cheese pizzas that Kaelani can order from Olava’s Pizza Company.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

the cost of each (large cheese) pizza / a pizza / one pizza / per pizza       (A1)   (C1)

Note: Award (A0) for “the cost of (large cheese) pizzas”. Do not accept “the minimum cost of a pizza”.

\n


[1 mark]

\n
a.i.
\n
\n

the (fixed) delivery cost      (A1)   (C1)

[1 mark]

\n
a.ii.
\n
\n

2     (A1)   (C1)

[1 mark]

\n
b.
\n
\n

450=34.50n+8.50        (M1)

\n

Note: Award (M1) for equating the cost equation to 450 (may be stated as an inequality).

\n


12.8  12.7971      (A1)

\n

12      (A1)(ft)   (C3)

\n


Note:
The final answer must be an integer.
The final (A1)(ft) is awarded for rounding their answer down to a whole number, provided their unrounded answer is seen.


[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Hafizah harvested 49 mangoes from her farm. The weights of the mangoes, w, in grams, are shown in the following grouped frequency table.

\n

\n
\n

Write down the modal group for these data.

\n
[1]
\n
a.
\n
\n

Use your graphic display calculator to find an estimate of the standard deviation of the weights of mangoes from this harvest.

\n
[2]
\n
b.
\n
\n

On the grid below, draw a histogram for the data in the table.

\n

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

400w<500        (A1)   (C1)

\n


Note: Accept alternative notation [400, 500) or [400, 500[.
Do not accept \"400-500\".

\n


[1 mark]

\n
a.
\n
\n

115   115.265(g)        (A2)   (C2)

\n


Note: Award (A1)(A0) for an answer of 116 116.459.

\n


[2 marks]

\n
b.
\n
\n

        (A2)(A1)   (C3)

\n


Note: Award (A2) for all correct heights of bars or (A1) for three or four correct heights of bars.
Award (A1) for rectangular bars all with correct left and right end points (100, 200, 300, 400, 500 and 600) and for no gaps; the bars do not have to be shaded.
Award at most (A2)(A0) if a ruler is not used for all lines.

\n


[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

In an international competition, participants can answer questions in only one of the three following languages: Portuguese, Mandarin or Hindi. 80 participants took part in the competition. The number of participants answering in Portuguese, Mandarin or Hindi is shown in the table.

\n

\n
\n

A boy is chosen at random.

\n
\n

State the number of boys who answered questions in Portuguese.

\n
[1]
\n
a.
\n
\n

Find the probability that the boy answered questions in Hindi.

\n
[2]
\n
b.
\n
\n

Two girls are selected at random.

\n

Calculate the probability that one girl answered questions in Mandarin and the other answered questions in Hindi.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

20     (A1) (C1)

\n

[1 mark]

\n
a.
\n
\n

\n\n5\n\n43\n\n\n\n\n\n\n(\n\n0.11627\n\n,\n\n\n11.6279\n\n\n\n\n\n)\n\n     (A1)(A1) (C2)

\n

Note: Award (A1) for correct numerator, (A1) for correct denominator.

\n

[2 marks]

\n
b.
\n
\n

\n\n7\n\n37\n\n\n×\n\n\n12\n\n\n36\n\n\n+\n\n\n12\n\n\n37\n\n\n×\n\n7\n\n36\n\n\n     (A1)(M1)

\n

Note: Award (A1) for first or second correct product seen, (M1) for adding their two products or for multiplying their product by two.

\n

\n=\n\n\n14\n\n\n111\n\n\n\n\n\n(\n\n\n0.12612\n\n,\n\n\n12.6126\n\n\n\n\n\n)\n\n     (A1) (C3)

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ2.T_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n6\nx\n\n1\n\n\n2\nx\n+\n3\n\n\n, for \nx\n\n\n\n3\n2\n\n.

\n
\n

For the graph of \nf\n, find the \ny\n-intercept.

\n
[2]
\n
a.i.
\n
\n

Hence or otherwise, write down \n\n\n\nlim\n\n\n\nx\n\n\n\n\n\n\n(\n\n\n\n6\nx\n\n1\n\n\n2\nx\n+\n3\n\n\n\n)\n\n.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid method      (M1)

\n

eg   \nf\n(0),  sketch of graph

\n

\ny\n-intercept is \n\n\n1\n3\n\n  (exact),  −0.333, \n\n(\n\n0\n,\n\n\n\n1\n3\n\n\n)\n\n       A1 N2

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

valid approach      (M1)

\n

eg   recognizing that \n\n\n\nlim\n\n\n\nx\n\n\n\n\n\nf\n\n(\nx\n)\n\n is related to the horizontal asymptote, 

\n

table with large values of \nx\n, their \ny\n value from (a)(iii), L’Hopital’s rule \n\n\n\nlim\n\n\n\nx\n\n\n\n\n\nf\n\n(\nx\n)\n\n=\n3\n.

\n

\n\n\n\nlim\n\n\n\nx\n\n\n\n\n\n\n(\n\n\n\n6\nx\n\n1\n\n\n2\nx\n+\n3\n\n\n\n)\n\n=\n3\n      A1 N2

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.2.SL.TZ0.S_3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-8-reciprocal-and-simple-rational-functions-equations-of-asymptotes" ] }, { "Question": "
\n

The graph of y=fx for -4x6 is shown in the following diagram.

\n

\n
\n

Write down the value of f2.

\n
[1]
\n
a.i.
\n
\n

Write down the value of ff2.

\n
[1]
\n
a.ii.
\n
\n

Let gx=12fx+1 for -4x6. On the axes above, sketch the graph of g.

\n

 

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

f2=6        A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

ff2=-2       A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

     M1A1A1

\n

 

\n

Note: Award M1 for an attempt to apply any vertical stretch or vertical translation, A1 for a correct horizontal line segment between 4 and 0 (located roughly at y=3),
A1 for a correct concave down parabola including max point at (2,4) and for correct end points at (0,3) and (6,0) (within circles). Points do not need to be labelled.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.SL.TZ1.1", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse", "sl-2-11-transformation-of-functions" ] }, { "Question": "
\n

Consider the graph of the function fx=x+12x2, x0.

\n

\n
\n

Write down the zero of fx.

\n
[2]
\n
a.i.
\n
\n

Write down the coordinates of the local minimum point.

\n
[2]
\n
a.ii.
\n
\n

Consider the function gx=3-x.

\n

Solve fx=gx.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

0=x+12x2        (M1)

\n


Note:
Award (M1) for equating the function to zero.

\n


x= -2.29  -2.28942       (A1)   (C2)

\n


Note: Award (C1) for a correct x-value given as part of a coordinate pair or alongside an explicitly stated y-value.

\n


[2 marks]

\n
a.i.
\n
\n

2.88, 4.33  2.88449, 4.32674        (A1)(A1)   (C2)

\n


Note:
 Accept x=2.88, y=4.33.

\n


[2 marks]

\n
a.ii.
\n
\n

3-x=x+12x2 (or equivalent)        (M1)

\n


Note:
Award (M1) for equating the functions or for a sketch of the two functions.

\n


x= -1.43  -1.43080        (A1)   (C2)

\n


Note:
Do not award the final (A1) if the answer is seen as part of a coordinate pair or a y-value is explicitly stated, unless already penalized in part (a).

\n


[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.1.SL.TZ0.T_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

Let a = \n\n(\n\n\n\n\n2\n\n\n\n\nk\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n and b = \n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\nk\n+\n2\n\n\n\n\n\nk\n\n\n\n\n)\n\n, \nk\n\n\nR\n\n.

\n

Given that a and b are perpendicular, find the possible values of \nk\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

a b = \n\n(\n\n\n\n\n2\n\n\n\n\nk\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\nk\n+\n2\n\n\n\n\n\nk\n\n\n\n\n)\n\n

\n

\n=\n\n6\n+\nk\n\n(\n\nk\n+\n2\n\n)\n\n\nk\n      A1

\n

a b = 0        (M1)

\n

\n\n\nk\n2\n\n\n+\nk\n\n6\n=\n0\n

\n

attempt at solving their quadratic equation        (M1)

\n

\n\n(\n\nk\n+\n3\n\n)\n\n\n(\n\nk\n\n2\n\n)\n\n=\n0\n

\n

\nk\n=\n\n3\n\n,\n\n\n\n2\n      A1

\n

Note: Attempt at solving using |a||b| = |a × b| will be M1A0A0A0 if neither answer found M1(A1)A1A0
for one correct answer and M1(A1)A1A1 for two correct answers.

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.AHL.TZ1.H_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The points A and B are given by \n\nA\n\n(\n0\n,\n\n \n\n3\n,\n\n \n\n\n6\n)\n and \n\nB\n\n(\n6\n,\n\n \n\n\n5\n,\n\n \n\n11\n)\n.

\n

The plane Π is defined by the equation \n4\nx\n\n3\ny\n+\n2\nz\n=\n20\n.

\n
\n

Find a vector equation of the line L passing through the points A and B.

\n
[3]
\n
a.
\n
\n

Find the coordinates of the point of intersection of the line L with the plane Π.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\nAB\n\n\n\n=\n\n(\n\n\n\n\n6\n\n\n\n\n\n\n8\n\n\n\n\n\n\n17\n\n\n\n\n\n)\n\n     (A1)

\n

 

\n

r = \n\n(\n\n\n\n\n0\n\n\n\n\n3\n\n\n\n\n\n\n6\n\n\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n6\n\n\n\n\n\n\n8\n\n\n\n\n\n\n17\n\n\n\n\n\n)\n\n or r = \n\n(\n\n\n\n\n6\n\n\n\n\n\n\n5\n\n\n\n\n\n\n11\n\n\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n6\n\n\n\n\n\n\n8\n\n\n\n\n\n\n17\n\n\n\n\n\n)\n\n     M1A1

\n

 

\n

Note:     Award M1A0 if r = is not seen (or equivalent).

\n

 

\n

[3 marks]

\n
a.
\n
\n

substitute line L in \nΠ\n:\n4\n(\n6\nλ\n)\n\n3\n(\n3\n\n8\nλ\n)\n+\n2\n(\n\n6\n+\n17\nλ\n)\n=\n20\n     M1

\n

\n82\nλ\n=\n41\n

\n

\nλ\n=\n\n1\n2\n\n     (A1)

\n

 

\n

r = \n\n(\n\n\n\n\n0\n\n\n\n\n3\n\n\n\n\n\n\n6\n\n\n\n\n\n)\n\n+\n\n1\n2\n\n\n(\n\n\n\n\n6\n\n\n\n\n\n\n8\n\n\n\n\n\n\n17\n\n\n\n\n\n)\n\n=\n\n(\n\n\n\n\n3\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n5\n2\n\n\n\n\n\n\n)\n\n

\n

so coordinate is \n\n(\n\n3\n,\n\n \n\n\n1\n,\n\n \n\n\n5\n2\n\n\n)\n\n     A1

\n

 

\n

Note:     Accept coordinate expressed as position vector \n\n(\n\n\n\n\n3\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n5\n2\n\n\n\n\n\n\n)\n\n.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.AHL.TZ0.H_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

Let f(x) = ln x − 5x , for x > 0 .

\n
\n

Solve f '(x) = f \"(x).

\n
", "Markscheme": "
\n

METHOD 1 (using GDC)

\n

valid approach      (M1)

\n

eg 

\n

0.558257

\n

x = 0.558       A1 N2

\n

Note: Do not award A1 if additional answers given.

\n

 

\n

METHOD 2 (analytical)

\n

attempt to solve their equation f '(x) = f \"(x)  (do not accept \n\n1\nx\n\n\n5\n=\n\n\n1\n\n\n\nx\n2\n\n\n\n\n)      (M1)

\n

eg  \n5\n\n\nx\n2\n\n\n\nx\n\n1\n=\n0\n,\n\n\n\n\n1\n±\n\n21\n\n\n\n10\n\n\n,\n\n\n\n1\nx\n\n=\n\n\n\n1\n±\n\n21\n\n\n2\n\n,\n\n\n\n0.358\n

\n

0.558257

\n

x = 0.558       A1 N2

\n

Note: Do not award A1 if additional answers given.

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.SL.TZ1.S_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

The diameter of a spherical planet is 6×104km.

\n
\n

Write down the radius of the planet.

\n
[1]
\n
a.
\n
\n

The volume of the planet can be expressed in the form πa×10kkm3 where 1a<10 and k.

\n

Find the value of a and the value of k.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

3×104  OR  30000km  (accept 3104)     A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

43π3×1043  OR  43π300003          (A1)

\n

=43π×27×1012 =π36×1012  OR  =43π×27000000000000          (A1)

\n

=π36×1013km3  OR  a=3.6, k=13          A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.SL.TZ1.2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Consider the vectors a ( 3 2 p ) and b = ( p + 1 8 ) .

\n

Find the possible values of p for which a and b are parallel.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1 (eliminating k)

\n

recognizing parallel vectors are multiples of each other      (M1)

\n

eg   a = kb,   ( 3 2 p ) k ( p + 1 8 ) ,   p + 1 3 = 8 2 p ,  3k = p + 1 and 2kp = 8

\n

correct working (must be quadratic)       (A1)

\n

eg   2p2 + 2p = 24,  p2 + p – 12,   3 = p 2 + p 4

\n

valid attempt to solve their quadratic equation       (M1)

\n

eg   factorizing, formula, completing the square

\n

evidence of correct working      (A1)

\n

eg   (p + 4)(p – 3),  x = 2 ± 4 4 ( 2 ) ( 24 ) 4

\n

p = –4,  p = 3     A1A1 N4

\n

 

\n

METHOD 2 (solving for k)

\n

recognizing parallel vectors are multiples of each other      (M1)

\n

eg   a = kb,   ( 3 2 p ) = k ( p + 1 8 ) ,  3k = p + 1 and 2kp = 8

\n

correct working (must be quadratic)       (A1)

\n

eg   3k2 – k = 4,  3k2 – k – 4,  4k2 = 3 – k

\n

one correct value for k      (A1)

\n

eg   k = –1, k =  4 3 ,  k =  3 4

\n

substituting their value(s) of k      (M1)

\n

eg    ( 3 2 p ) = 3 4 ( p + 1 8 ) ,   3 ( 4 3 ) = p + 1 and  2 ( 4 3 ) p = 8 ,   ( 1 ) ( 3 2 p ) = ( p + 1 8 )

\n

p = –4,  p = 3     A1A1 N4

\n

 

\n

METHOD 3 (working with angles and cosine formula)

\n

recognizing angle between parallel vectors is 0 and/or 180°      M1

\n

eg   cos θ = ±1,   a b = | a | | b |

\n

correct substitution of scalar product and magnitudes into equation      (A1)

\n

eg  3 ( p + 1 ) + 2 p ( 8 ) 3 2 + ( 2 p ) 2 ( p + 1 ) 2 + 8 2 = ± 1 ,   19 p + 3 = 4 p 2 + 9 p 2 + 2 p + 65

\n

correct working (must include both ± )      (A1)

\n

eg  3 ( p + 1 ) + 2 p ( 8 ) = ± 3 2 + ( 2 p ) 2 ( p + 1 ) 2 + 8 2 ,   19 p + 3 = ± 4 p 2 + 9 p 2 + 2 p + 65

\n

correct quartic equation      (A1)

\n

eg    361 p 2 + 114 p + 9 = 4 p 4 + 8 p 3 + 269 p 2 + 18 p + 585 ,   4 p 4 + 8 p 3 92 p 2 96 p + 576 = 0 ,   p 4 + 2 p 3 23 p 2 24 p + 144 = 0 ,    ( p + 4 ) 2 ( p 3 ) 2 = 0

\n

p = –4,  p = 3     A2 N4

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.1.SL.TZ0.S_5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

A tetrahedral (four-sided) die has written on it the numbers 1, 2, 3 and 4. The die is rolled many times and the scores are noted. The table below shows the resulting frequency distribution.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/07\"

\n

The die was rolled a total of 100 times.

\n
\n

The mean score is 2.71.

\n
\n

Write down an equation, in terms of \nx\n and \ny\n, for the total number of times the die was rolled.

\n
[1]
\n
a.
\n
\n

Using the mean score, write down a second equation in terms of \nx\n and \ny\n.

\n
[2]
\n
b.
\n
\n

Find the value of \nx\n and of \ny\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n18\n+\nx\n+\ny\n+\n22\n=\n100\n or equivalent     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

\n\n\n18\n+\n2\nx\n+\n3\ny\n+\n88\n\n\n100\n\n\n=\n2.71\n or equivalent     (M1)(A1)     (C2)

\n

 

\n

Note:     Award (M1) for a sum including \nx\n and \ny\n, divided by 100 and equated to 2.71, (A1) for a correct equation.

\n

 

\n

[2 marks]

\n
b.
\n
\n

\nx\n+\ny\n=\n60\n and \n2\nx\n+\n3\ny\n=\n165\n     (M1)

\n

 

\n

Note:     Award (M1) for obtaining a correct linear equation in one variable from their (a) and their (b).

\n

This may be implied if seen in part (a) or part (b).

\n

 

\n

\nx\n=\n15\n;\n\n \n\ny\n=\n45\n     (A1)(ft)(A1)(ft)     (C3)

\n

 

\n

Notes:     Follow through from parts (a) and (b), irrespective of working seen provided the answers are positive integers.

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Consider a triangle OAB such that O has coordinates (0, 0, 0), A has coordinates (0, 1, 2) and B has coordinates (2\nb\n, 0, \nb\n − 1) where \nb\n < 0.

\n
\n

Let M be the midpoint of the line segment [OB].

\n
\n

Find, in terms of \nb\n, a Cartesian equation of the plane Π containing this triangle.

\n
[5]
\n
a.
\n
\n

Find, in terms of \nb\n, the equation of the line L which passes through M and is perpendicular to the plane П.

\n
[3]
\n
b.
\n
\n

Show that L does not intersect the \ny\n-axis for any negative value of \nb\n.

\n

 

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\nn\n=\n\n(\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n2\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n\n2\nb\n\n\n\n\n\n0\n\n\n\n\n\nb\n\n1\n\n\n\n\n\n)\n\n      (M1)

\n

\n=\n\n(\n\n\n\n\n\nb\n\n1\n\n\n\n\n\n\n4\nb\n\n\n\n\n\n\n\n2\nb\n\n\n\n\n\n)\n\n      (M1)A1

\n

(0, 0, 0) on Π so \n\n(\n\nb\n\n1\n\n)\n\nx\n+\n4\nb\ny\n\n2\nb\nz\n=\n0\n      (M1)A1

\n

 

\n

METHOD 2

\n

using equation of the form \np\nx\n+\nq\ny\n+\nr\nz\n=\n0\n      (M1)

\n

(0, 1, 2) on Π ⇒ \nq\n+\n2\nr\n=\n0\n

\n

(2\nb\n, 0, \nb\n − 1) on Π ⇒ \n2\nb\np\n+\nr\n\n(\n\nb\n\n1\n\n)\n\n=\n0\n      (M1)A1

\n

Note: Award (M1)A1 for both equations seen.

\n

solve for \np\n\nq\n and \nr\n      (M1)

\n

\n\n(\n\nb\n\n1\n\n)\n\nx\n+\n4\nb\ny\n\n2\nb\nz\n=\n0\n      A1

\n

 

\n

[5 marks]

\n
a.
\n
\n

M has coordinates \n\n(\n\nb\n,\n\n\n0\n,\n\n\n\n\nb\n\n1\n\n2\n\n\n)\n\n      (A1)

\n

r\n\n(\n\n\n\n\nb\n\n\n\n\n0\n\n\n\n\n\n\n\nb\n\n1\n\n2\n\n\n\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n\nb\n\n1\n\n\n\n\n\n\n4\nb\n\n\n\n\n\n\n\n2\nb\n\n\n\n\n\n)\n\n      M1A1

\n

Note: Award M1A0 if r = (or equivalent) is not seen.

\n

Note: Allow equivalent forms such as \n\n\nx\n\nb\n\n\nb\n\n1\n\n\n=\n\ny\n\n4\nb\n\n\n=\n\n\n2\nz\n\nb\n+\n1\n\n\n\n4\nb\n\n\n.

\n

 

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

\nx\n=\nz\n=\n0\n      (M1)

\n

Note: Award M1 for either \nx\n=\n0\n or \nz\n=\n0\n or both.

\n

\nb\n+\nλ\n\n(\n\nb\n\n1\n\n)\n\n=\n0\n and \n\n\nb\n\n1\n\n2\n\n\n2\nλ\nb\n=\n0\n      A1

\n

attempt to eliminate \nλ\n       M1

\n

\n\n\n\nb\n\nb\n\n1\n\n\n=\n\n\nb\n\n1\n\n\n4\nb\n\n\n      (A1)

\n

\n\n4\n\n\nb\n2\n\n\n=\n\n\n\n(\n\nb\n\n1\n\n)\n\n2\n\n\n      A1

\n

EITHER

\n

consideration of the signs of LHS and RHS       (M1)

\n

the LHS is negative and the RHS must be positive (or equivalent statement)       R1

\n

OR

\n

\n\n4\n\n\nb\n2\n\n\n=\n\n\nb\n2\n\n\n\n2\nb\n+\n1\n

\n

\n\n5\n\n\nb\n2\n\n\n\n2\nb\n+\n1\n=\n0\n

\n

\nΔ\n=\n\n\n\n(\n\n\n2\n\n)\n\n2\n\n\n\n4\n×\n5\n×\n1\n=\n\n16\n\n\n(\n\n<\n0\n\n)\n\n     M1

\n

\n\n no real solutions       R1

\n

THEN

\n

so no point of intersection       AG

\n

 

\n

METHOD 2

\n

\nx\n=\nz\n=\n0\n      (M1)

\n

Note: Award M1 for either \nx\n=\n0\n or \nz\n=\n0\n or both.

\n

\nb\n+\nλ\n\n(\n\nb\n\n1\n\n)\n\n=\n0\n and \n\n\nb\n\n1\n\n2\n\n\n2\nλ\nb\n=\n0\n      A1

\n

attempt to eliminate \nb\n       M1

\n

\n\n\nλ\n\n1\n+\nλ\n\n\n=\n\n1\n\n1\n\n4\nλ\n\n\n      (A1)

\n

\n\n4\n\n\nλ\n2\n\n\n=\n1\n\n(\n\n\n\n\nλ\n2\n\n\n=\n\n\n1\n4\n\n\n)\n\n      A1

\n

consideration of the signs of LHS and RHS       (M1)

\n

there are no real solutions (or equivalent statement)       R1

\n

so no point of intersection       AG

\n

 

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.1.AHL.TZ0.H_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

Consider an arithmetic sequence where u8=S8=8. Find the value of the first term, u1, and the value of the common difference, d.

\n
", "Markscheme": "
\n

METHOD 1 (finding u1 first, from S8)

\n

4u1+8=8          (A1)

\n

u1=-6          A1

\n

u1+7d=8  OR  42u1+7d=8  (may be seen with their value of u1)          (A1)

\n

attempt to substitute their u1          (M1)

\n

d=2          A1

\n

 

\n

METHOD 2 (solving simultaneously)

\n

u1+7d=8          (A1)

\n

4u1+8=8  OR  42u1+7d=8  OR  u1=-3d          (A1)

\n

attempt to solve linear or simultaneous equations          (M1)

\n

u1=-6, d=2          A1A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.SL.TZ1.3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

OAB is a sector of the circle with centre O and radius \nr\n, as shown in the following diagram.

\n

\n

The angle AOB is \nθ\n radians, where \n0\n<\nθ\n<\n\nπ\n2\n\n.

\n

The point C lies on OA and OA is perpendicular to BC.

\n
\n

Show that OC = r cos θ .

\n
[1]
\n
a.
\n
\n

Find the area of triangle OBC in terms of r and θ.

\n
[2]
\n
b.
\n
\n

Given that the area of triangle OBC is  3 5  of the area of sector OAB, find θ.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

cos θ = OC r      A1

\n

OC = r cos θ   AG N0

\n

[1 mark]

\n
a.
\n
\n

valid approach    (M1)

\n

eg    1 2 OC × OB sin θ ,   BC = r sin θ 1 2 r cos θ × BC ,   1 2 r sin θ × OC

\n

area = 1 2 r 2 sin θ cos θ   ( = 1 4 r 2 sin ( 2 θ ) )   (must be in terms of r and θ)      A1 N2

\n

[2 marks]

\n
b.
\n
\n

valid attempt to express the relationship between the areas (seen anywhere)        (M1)

\n

eg   OCB =  3 5 OBA ,   1 2 r 2 sin θ cos θ = 3 5 × 1 2 r 2 θ ,   1 4 r 2 sin 2 θ = 3 10 r 2 θ

\n

correct equation in terms of θ only      A1

\n

eg    sin θ cos θ = 3 5 θ ,   1 4 sin 2 θ = 3 10 θ

\n

valid attempt to solve their equation        (M1)

\n

eg    sketch,  −0.830017,  0

\n

0.830017

\n

θ = 0.830      A1 N2

\n

Note: Do not award final A1 if additional answers given.

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.SL.TZ2.S_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

A research student weighed lizard eggs in grams and recorded the results. The following box and whisker diagram shows a summary of the results where L and U are the lower and upper quartiles respectively.

\n

\n

The interquartile range is 20 grams and there are no outliers in the results.

\n
\n

Find the minimum possible value of U.

\n
[3]
\n
a.
\n
\n

Hence, find the minimum possible value of L.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

attempt to use definition of outlier

\n

1.5×20+Q3          (M1)

\n

1.5×20+U75 (U45, accept U>45)  OR  1.5×20+Q3=75          A1

\n

minimum value of U=45          A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to use interquartile range         (M1)

\n

U-L=20  (may be seen in part (a))  OR  L25 (accept L>25)

\n

minimum value of L=25          A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.SL.TZ1.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

Consider the functions fx=-x-h2+2k and gx=ex-2+k where h,k.

\n
\n

The graphs of f and g have a common tangent at x=3.

\n
\n

Find f'x.

\n
[1]
\n
a.
\n
\n

Show that h=e+62.

\n
[3]
\n
b.
\n
\n

Hence, show that k=e+e24.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

f'x=-2x-h          A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

g'x=ex-2  OR  g'3=e3-2 (may be seen anywhere)          A1

\n

 

\n

Note: The derivative of g must be explicitly seen, either in terms of x or 3.

\n

 

\n

recognizing f'3=g'3          (M1)

\n

-23-h=e3-2  =e

\n

-6+2h=e  OR  3-h=-e2          A1

\n

 

\n

Note: The final A1 is dependent on one of the previous marks being awarded.

\n

 

\n

h=e+62          AG

\n

 

\n

[3 marks]

\n
b.
\n
\n

f3=g3          (M1)

\n

-3-h2+2k=e3-2+k

\n

correct equation in k

\n

 

\n

EITHER

\n

-3-e+622+2k=e3-2+k          A1

\n

k=e+6-e-622 =e+-e22          A1

\n

 

\n

OR

\n

k=e+3-e+622          A1

\n

k=e+9-3e-18+e2+12e+364          A1

\n

 

\n

THEN

\n

k=e+e24          AG

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.1.SL.TZ1.5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Consider the lines \n\n\nl\n1\n\n\n and \n\n\nl\n2\n\n\n defined by

\n

\n\n\nl\n1\n\n\n:\n r \n=\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\n2\n\n\n\n\n\na\n\n\n\n\n)\n\n+\nβ\n\n(\n\n\n\n\n1\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n and \n\n\nl\n2\n\n\n:\n\n\n6\n\nx\n\n3\n\n=\n\n\ny\n\n2\n\n4\n\n=\n1\n\nz\n where \na\n is a constant.

\n

Given that the lines \n\n\nl\n1\n\n\n and \n\n\nl\n2\n\n\n intersect at a point P,

\n
\n

find the value of \na\n;

\n
[4]
\n
a.
\n
\n

determine the coordinates of the point of intersection P.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\n\nl\n1\n\n\n:\nr \n=\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\n2\n\n\n\n\n\na\n\n\n\n\n)\n\n=\nβ\n\n(\n\n\n\n\n1\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n\n\n{\n\n\n\n\n\nx\n=\n\n3\n+\nβ\n\n\n\n\n\n\ny\n=\n\n2\n+\n4\nβ\n\n\n\n\n\n\nz\n=\na\n+\n2\nβ\n\n\n\n\n\n\n\n     M1

\n

\n\n\n6\n\n(\n\n3\n+\nβ\n)\n\n3\n\n=\n\n\n(\n\n2\n+\n4\nβ\n)\n\n2\n\n4\n\n\n4\n=\n\n\n4\nβ\n\n3\n\n\nβ\n=\n3\n    M1A1

\n

\n\n\n6\n\n(\n\n3\n+\nβ\n)\n\n3\n\n=\n1\n\n(\na\n+\n2\nβ\n)\n\n2\n=\n\n5\n\na\n\na\n=\n\n7\n    A1

\n

METHOD 2

\n

\n\n{\n\n\n\n\n\n\n3\n+\nβ\n=\n6\n\n3\nλ\n\n\n\n\n\n\n\n2\n+\n4\nβ\n=\n4\nλ\n+\n2\n\n\n\n\n\n\na\n+\n2\nβ\n=\n1\n\nλ\n\n\n\n\n\n\n\n    M1

\n

attempt to solve     M1

\n

\nλ\n=\n2\n,\n\n \n\nβ\n=\n3\n    A1

\n

\na\n=\n1\n\nλ\n\n2\nβ\n=\n\n7\n    A1

\n

[4 marks]

\n
a.
\n
\n

\n\n\nOP\n\n\n\n=\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\n2\n\n\n\n\n\n\n\n7\n\n\n\n\n\n)\n\n+\n3\n\n\n(\n\n\n\n\n1\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n    (M1)

\n

\n=\n\n(\n\n\n\n\n0\n\n\n\n\n\n10\n\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n    A1

\n

\n\n\nP\n\n(\n0\n,\n\n 10, \n\n\n1\n)\n

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.AHL.TZ0.H_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

The following diagram shows triangle PQR.

\n

\"M17/5/MATME/SP1/ENG/TZ1/03\"

\n

Find PR.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 

\n

evidence of choosing the sine rule     (M1)

\n

eg\n\n\n\n\n\n\n\na\n\nsin\n\nA\n\n\n=\n\nb\n\nsin\n\nB\n\n\n

\n

correct substitution     A1

\n

eg\n\n\n\n\n\n\n\nx\n\nsin\n\n30\n\n\n=\n\n\n13\n\n\nsin\n\n45\n\n\n,\n\n \n\n\n\n13\nsin\n\n30\n\n\nsin\n\n45\n\n\n

\n

\nsin\n\n30\n=\n\n1\n2\n\n,\n\n \n\nsin\n\n45\n=\n\n1\n\n\n2\n\n\n\n     (A1)(A1)

\n

correct working     A1

\n

eg\n\n\n\n\n\n\n\n1\n2\n\n×\n\n\n13\n\n\n\n1\n\n\n2\n\n\n\n\n\n,\n\n \n\n\n1\n2\n\n×\n13\n×\n\n2\n\n\n2\n\n\n\n,\n\n \n\n13\n×\n\n1\n2\n\n×\n\n2\n\n

\n

correct answer     A1     N3

\n

eg\n\n\n\n\n\n\n\nPR\n\n=\n\n\n13\n\n2\n\n\n2\n\n,\n\n \n\n\n\n13\n\n\n\n2\n\n\n\n\n (cm)\n\n

\n

METHOD 2 (using height of ΔPQR)

\n

valid approach to find height of ΔPQR     (M1)

\n

eg\n\n\n\n\n\n\nsin\n\n30\n=\n\nx\n\n13\n\n\n,\n\n \n\ncos\n\n60\n=\n\nx\n\n13\n\n\n

\n

\nsin\n\n30\n=\n\n1\n2\n\n\n or \n\ncos\n\n60\n=\n\n1\n2\n\n     (A1)

\n

\n\nheight\n\n=\n6.5\n     A1

\n

correct working     A1

\n

eg\n\n\n\n\n\n\nsin\n\n45\n=\n\n\n6.5\n\n\n\nPR\n\n\n\n,\n\n \n\n\n\n\n\n6.5\n\n2\n\n\n+\n\n\n\n6.5\n\n2\n\n\n\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\nsin\n\n45\n=\n\n1\n\n\n2\n\n\n\n,\n\n \n\ncos\n\n45\n=\n\n1\n\n\n2\n\n\n\n,\n\n \n\n\n\n\n169\n×\n2\n\n4\n\n\n

\n

correct answer     A1     N3

\n

eg\n\n\n\n\n\n\n\nPR\n\n=\n\n\n13\n\n2\n\n\n2\n\n,\n\n \n\n\n\n13\n\n\n\n2\n\n\n\n\n (cm)\n\n

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.SL.TZ1.S_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Consider the graph of the function \nf\n\n(\nx\n)\n\n=\n2\n\n\nsin\n\n\nx\n,  0 ≤ \nx\n < \n2\nπ\n . The graph of \nf\n intersects the line \ny\n=\n\n1\n exactly twice, at point A and point B. This is shown in the following diagram.

\n

\n
\n

Consider the graph of  g ( x ) = 2 sin p x , 0 ≤ x < 2 π , where p > 0.

\n

Find the greatest value of p such that the graph of g does not intersect the line y = 1 .

\n
", "Markscheme": "
\n

recognizing period of  g is larger than the period of  f         (M1)

\n

eg   sketch of g with larger period (may be seen on diagram), A at  x = 2 π ,

\n

      image of A when  x > 2 π ,   7 π 6 2 π ,   2 sin ( 2 π p ) = 1 ,   7 π 6 × k = 2 π

\n

correct working       (A1)

\n

eg    7 π 6 1 p = 2 π ,   2 π p = 7 π 6 ,   12 7

\n

p = 7 12     ( accept p < 7 12 or p 7 12 )        A1  N2

\n

[3 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.SL.TZ2.S_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

The histogram shows the lengths of 25 metal rods, each measured correct to the nearest cm.

\n

\n
\n

The upper quartile is 4 cm.

\n
\n

Write down the modal length of the rods.

\n
[1]
\n
a.
\n
\n

Find the median length of the rods.

\n
[3]
\n
b.
\n
\n

Calculate the lower quartile.

\n
[1]
\n
c.i.
\n
\n

Calculate the interquartile range.

\n
[1]
\n
c.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

3     (A1) (C1)
 

\n

[1 mark]

\n
a.
\n
\n

median is 13th position      (M1)

\n

CF: 2, 6, 14, 20, 23, 25       (M1)

\n

median = 3      (A1) (C3)

\n

 

\n

[3 marks]

\n
b.
\n
\n

2.5       (A1) (C1)

\n

 

\n

Note: Award (A1)(ft) if the sum of their parts (c)(i) and (c)(ii) is 4.

\n

 

\n

[1 mark]

\n
c.i.
\n
\n

1.5       (A1)(ft)  (C1)

\n

 

\n

Note: Award (A1)(ft) if the sum of their parts (c)(i) and (c)(ii) is 4.

\n

 

\n

[1 mark]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "18N.1.SL.TZ0.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Given that a \n×\n b \n=\n b \n×\n c \n\n 0 prove that a \n+\n c \n=\n sb where s is a scalar.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

a \n×\n b = b \n×\n c

\n

(a \n×\n b) \n\n (b \n×\n c) = 0

\n

(a \n×\n b) + (c \n×\n b) = 0     M1A1

\n

(a + c) \n×\n b = 0     A1

\n

(a + c) is parallel to b \n\n a + c = sb     R1AG

\n

 

\n

Note:     Condone absence of arrows, underlining, or other otherwise “correct” vector notation throughout this question.

\n

 

\n

Note:     Allow “is in the same direction to”, for the final R mark.

\n

 

\n

METHOD 2

\n

a \n×\n b = b \n×\n c \n\n\n(\n\n\n\n\n\n\n\na\n2\n\n\n\n\nb\n3\n\n\n\n\n\na\n3\n\n\n\n\nb\n2\n\n\n\n\n\n\n\n\n\n\na\n3\n\n\n\n\nb\n1\n\n\n\n\n\na\n1\n\n\n\n\nb\n3\n\n\n\n\n\n\n\n\n\n\na\n1\n\n\n\n\nb\n2\n\n\n\n\n\na\n2\n\n\n\n\nb\n1\n\n\n\n\n\n\n\n)\n\n=\n\n(\n\n\n\n\n\n\n\nb\n2\n\n\n\n\nc\n3\n\n\n\n\n\nb\n3\n\n\n\n\nc\n2\n\n\n\n\n\n\n\n\n\n\nb\n3\n\n\n\n\nc\n1\n\n\n\n\n\nb\n1\n\n\n\n\nc\n3\n\n\n\n\n\n\n\n\n\n\nb\n1\n\n\n\n\nc\n2\n\n\n\n\n\nb\n2\n\n\n\n\nc\n1\n\n\n\n\n\n\n\n)\n\n     M1A1

\n

\n\n\na\n2\n\n\n\n\nb\n3\n\n\n\n\n\na\n3\n\n\n\n\nb\n2\n\n\n=\n\n\nb\n2\n\n\n\n\nc\n3\n\n\n\n\n\nb\n3\n\n\n\n\nc\n2\n\n\n\n\n\nb\n3\n\n\n(\n\n\na\n2\n\n\n+\n\n\nc\n2\n\n\n)\n=\n\n\nb\n2\n\n\n(\n\n\na\n3\n\n\n+\n\n\nc\n3\n\n\n)\n

\n

\n\n\na\n3\n\n\n\n\nb\n1\n\n\n\n\n\na\n1\n\n\n\n\nb\n3\n\n\n=\n\n\nb\n3\n\n\n\n\nc\n1\n\n\n\n\n\nb\n1\n\n\n\n\nc\n3\n\n\n\n\n\nb\n1\n\n\n(\n\n\na\n3\n\n\n+\n\n\nc\n3\n\n\n)\n=\n\n\nb\n3\n\n\n(\n\n\na\n1\n\n\n+\n\n\nc\n1\n\n\n)\n

\n

\n\n\na\n1\n\n\n\n\nb\n2\n\n\n\n\n\na\n2\n\n\n\n\nb\n1\n\n\n=\n\n\nb\n1\n\n\n\n\nc\n2\n\n\n\n\n\nb\n2\n\n\n\n\nc\n1\n\n\n\n\n\nb\n2\n\n\n(\n\n\na\n1\n\n\n+\n\n\nc\n1\n\n\n)\n=\n\n\nb\n1\n\n\n(\n\n\na\n2\n\n\n+\n\n\nc\n2\n\n\n)\n

\n

\n\n\n(\n\n\na\n1\n\n\n+\n\n\nc\n1\n\n\n)\n\n\n\n\nb\n1\n\n\n\n\n=\n\n\n(\n\n\na\n2\n\n\n+\n\n\nc\n2\n\n\n)\n\n\n\n\nb\n2\n\n\n\n\n=\n\n\n(\n\n\na\n3\n\n\n+\n\n\nc\n3\n\n\n)\n\n\n\n\nb\n3\n\n\n\n\n=\ns\n     A1

\n

\n\n\n\na\n1\n\n\n+\n\n\nc\n1\n\n\n=\ns\n\n\nb\n1\n\n\n

\n

\n\n\n\na\n2\n\n\n+\n\n\nc\n2\n\n\n=\ns\n\n\nb\n2\n\n\n

\n

\n\n\n\na\n3\n\n\n+\n\n\nc\n3\n\n\n=\ns\n\n\nb\n3\n\n\n

\n

\n\n\n(\n\n\n\n\n\n\n\na\n1\n\n\n\n\n\n\n\n\n\n\na\n2\n\n\n\n\n\n\n\n\n\n\na\n3\n\n\n\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n\n\n\nc\n1\n\n\n\n\n\n\n\n\n\n\nc\n2\n\n\n\n\n\n\n\n\n\n\nc\n3\n\n\n\n\n\n\n\n)\n\n=\ns\n\n(\n\n\n\n\n\n\n\nb\n1\n\n\n\n\n\n\n\n\n\n\nb\n2\n\n\n\n\n\n\n\n\n\n\nb\n3\n\n\n\n\n\n\n\n)\n\n     A1

\n

\n\n a + c = sb     AG

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.AHL.TZ2.H_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-16-vector-product" ] }, { "Question": "
\n

The following table shows a probability distribution for the random variable \nX\n, where \n\nE\n\n(\nX\n)\n=\n1.2\n.

\n

\"M17/5/MATME/SP2/ENG/TZ2/10\"

\n
\n

A bag contains white and blue marbles, with at least three of each colour. Three marbles are drawn from the bag, without replacement. The number of blue marbles drawn is given by the random variable \nX\n.

\n
\n

A game is played in which three marbles are drawn from the bag of ten marbles, without replacement. A player wins a prize if three white marbles are drawn.

\n
\n

Find q .

\n
[2]
\n
a.i.
\n
\n

Find p .

\n
[2]
\n
a.ii.
\n
\n

Write down the probability of drawing three blue marbles.

\n
[1]
\n
b.i.
\n
\n

Explain why the probability of drawing three white marbles is 1 6 .

\n
[1]
\n
b.ii.
\n
\n

The bag contains a total of ten marbles of which w are white. Find w .

\n
[3]
\n
b.iii.
\n
\n

Jill plays the game nine times. Find the probability that she wins exactly two prizes.

\n
[2]
\n
c.
\n
\n

Grant plays the game until he wins two prizes. Find the probability that he wins his second prize on his eighth attempt.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

correct substitution into E ( X ) formula     (A1)

\n

eg 0 ( p ) + 1 ( 0.5 ) + 2 ( 0.3 ) + 3 ( q ) = 1.2

\n

q = 1 30 , 0.0333     A1     N2

\n

[2 marks]

\n
a.i.
\n
\n

evidence of summing probabilities to 1     (M1)

\n

eg p + 0.5 + 0.3 + q = 1

\n

p = 1 6 ,   0.167     A1     N2

\n

[2 marks]

\n
a.ii.
\n
\n

P (3 blue) = 1 30 ,   0.0333     A1     N1

\n

[1 mark]

\n
b.i.
\n
\n

valid reasoning     R1

\n

eg P (3 white) = P(0 blue)

\n

P(3 white) = 1 6     AG     N0

\n

[1 mark]

\n
b.ii.
\n
\n

valid method     (M1)

\n

eg P(3 white) = w 10 × w 1 9 × w 2 8 ,   w C 3 10 C 3

\n

correct equation     A1

\n

eg w 10 × w 1 9 × w 2 8 = 1 6 ,   w C 3 10 C 3 = 0.167

\n

w = 6     A1     N2

\n

[3 marks]

\n
b.iii.
\n
\n

valid approach     (M1)

\n

eg B ( n ,   p ) ,   ( n r ) p r q n r ,   ( 0.167 ) 2 ( 0.833 ) 7 ,   ( 9 2 )

\n

0.279081

\n

0.279     A1     N2

\n

[2 marks]

\n
c.
\n
\n

recognizing one prize in first seven attempts     (M1)

\n

eg ( 7 1 ) ,   ( 1 6 ) 1 ( 5 6 ) 6

\n

correct working     (A1)

\n

eg ( 7 1 ) ( 1 6 ) 1 ( 5 6 ) 6 ,   0.390714

\n

correct approach     (A1)

\n

eg ( 7 1 ) ( 1 6 ) 1 ( 5 6 ) 6 × 1 6

\n

0.065119

\n

0.0651     A1     N2

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.2.SL.TZ2.S_10", "topics": [ "topic-4-statistics-and-probability", "topic-2-functions" ], "subtopics": [ "sl-4-7-discrete-random-variables", "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

Consider the vectors a \n=\n i \n\n\n \n\n3\nj \n\n\n \n\n2\nk, b \n=\n\n\n \n\n3\nj \n+\n\n \n\n2\nk.

\n
\n

Find a \n×\n b.

\n
[2]
\n
a.
\n
\n

Hence find the Cartesian equation of the plane containing the vectors a and b, and passing through the point \n(\n1\n,\n\n \n\n0\n,\n\n \n\n\n1\n)\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

a \n×\n b \n=\n\n12\ni \n\n\n \n\n2\nj \n\n\n \n\n3\nk     (M1)A1

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

\n\n12\nx\n\n2\ny\n\n3\nz\n=\nd\n    M1

\n

\n\n12\n×\n1\n\n2\n×\n0\n\n3\n(\n\n1\n)\n=\nd\n    (M1)

\n

\n\nd\n=\n\n9\n    A1

\n

\n\n12\nx\n\n2\ny\n\n3\nz\n=\n\n9\n\n \n\n(\n\nor \n\n12\nx\n+\n2\ny\n+\n3\nz\n=\n9\n)\n

\n

METHOD 2

\n

\n\n(\n\n\n\n\nx\n\n\n\n\ny\n\n\n\n\nz\n\n\n\n\n)\n\n\n\n(\n\n\n\n\n\n\n12\n\n\n\n\n\n\n\n2\n\n\n\n\n\n\n\n3\n\n\n\n\n\n)\n\n=\n\n(\n\n\n\n\n1\n\n\n\n\n0\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n\n\n(\n\n\n\n\n\n\n12\n\n\n\n\n\n\n\n2\n\n\n\n\n\n\n\n3\n\n\n\n\n\n)\n\n    M1A1

\n

\n\n12\nx\n\n2\ny\n\n3\nz\n=\n\n9\n\n \n\n(\n\nor \n\n12\nx\n+\n2\ny\n+\n3\nz\n=\n9\n)\n    A1

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.AHL.TZ0.H_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-16-vector-product" ] }, { "Question": "
\n

The following diagram shows triangle ABC, with \n\nAB\n\n=\n3\n\n cm\n\n, \n\nBC\n\n=\n8\n\n cm\n\n, and \n\n\nA\n\n\nB\n^\n\n\nC\n=\n\n\n\nπ\n3\n\n.

\n

\"N17/5/MATME/SP1/ENG/TZ0/04\"

\n
\n

Show that \n\nAC\n\n=\n7\n\n cm\n\n.

\n
[4]
\n
a.
\n
\n

The shape in the following diagram is formed by adding a semicircle with diameter [AC] to the triangle.

\n

\"N17/5/MATME/SP1/ENG/TZ0/04.b\"

\n

Find the exact perimeter of this shape.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of choosing the cosine rule     (M1)

\n

eg\n\n\n\n\n\n\n\n\nc\n2\n\n\n=\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\na\nb\ncos\n\nC\n

\n

correct substitution into RHS of cosine rule     (A1)

\n

eg\n\n\n\n\n\n\n\n\n3\n2\n\n\n+\n\n\n8\n2\n\n\n\n2\n×\n3\n×\n8\n×\ncos\n\n\nπ\n3\n\n

\n

evidence of correct value for \ncos\n\n\nπ\n3\n\n (may be seen anywhere, including in cosine rule)     A1

\n

eg\n\n\n\n\n\n\ncos\n\n\nπ\n3\n\n=\n\n1\n2\n\n,\n\n A\n\n\n\n\nC\n\n2\n\n\n=\n9\n+\n64\n\n\n(\n\n48\n×\n\n1\n2\n\n\n)\n\n,\n\n \n\n9\n+\n64\n\n24\n

\n

correct working clearly leading to answer     A1

\n

eg\n\n\n\n\n\n\n\nA\n\n\n\n\nC\n\n2\n\n\n=\n49\n,\n\n \n\nb\n=\n\n49\n\n

\n

\n\nAC\n\n=\n7\n\n (cm)\n\n     AG     N0

\n

 

\n

Note:     Award no marks if the only working seen is \n\nA\n\n\n\n\nC\n\n2\n\n\n=\n49\n or \n\nAC\n\n=\n\n49\n\n (or similar).

\n

 

\n

[4 marks]

\n
a.
\n
\n

correct substitution for semicircle     (A1)

\n

eg\n\n\n\n\n\n\n\nsemicircle\n\n=\n\n1\n2\n\n(\n2\nπ\n×\n3.5\n)\n,\n\n \n\n\n1\n2\n\n×\nπ\n×\n7\n,\n\n \n\n3.5\nπ\n

\n

valid approach (seen anywhere)     (M1)

\n

eg\n\n\n\n\n\n\n\nperimeter\n\n=\n\nAB\n\n+\n\nBC\n\n+\n\nsemicircle, \n\n3\n+\n8\n+\n\n(\n\n\n1\n2\n\n×\n2\n×\nπ\n×\n\n7\n2\n\n\n)\n\n,\n\n \n\n8\n+\n3\n+\n3.5\nπ\n

\n

\n11\n+\n\n7\n2\n\nπ\n\n \n\n(\n=\n3.5\nπ\n+\n11\n)\n\n (cm)\n\n     A1     N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.SL.TZ0.S_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The following diagram shows the chord [AB] in a circle of radius 8 cm, where AB = 12  cm .

\n

\"M17/5/MATME/SP2/ENG/TZ1/05\"

\n

Find the area of the shaded segment.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to find the central angle or half central angle     (M1)

\n

eg \"M17/5/MATME/SP2/ENG/TZ1/05/M\", cosine rule, right triangle

\n

correct working     (A1)

\n

eg cos θ = 8 2 + 8 2 12 2 2 8 8 ,   sin 1 ( 6 8 ) ,   0.722734 ,   41.4096 ,   π 2 sin 1 ( 6 8 )

\n

correct angle A O ^ B (seen anywhere) 

\n

eg 1.69612,  97.1807 ,  2 × si n 1 ( 6 8 )     (A1)

\n

correct sector area

\n

eg 1 2 ( 8 ) ( 8 ) ( 1.70 ) ,   97.1807 360 ( 64 π ) ,   54.2759     (A1) 

\n

area of triangle (seen anywhere)     (A1) 

\n

eg 1 2 ( 8 ) ( 8 ) sin 1.70 ,   1 2 ( 8 ) ( 12 ) sin 0.722 ,   1 2 × 64 36 × 12 ,   31.7490

\n

appropriate approach (seen anywhere)     (M1)

\n

eg A triangle A sector , their sector-their triangle

\n

22.5269

\n

area of shaded region = 22.5   ( c m 2 )     A1     N4

\n

 

\n

Note:     Award M0A0A0A0A1 then M1A0 (if appropriate) for correct triangle area without any attempt to find an angle in triangle OAB.

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.SL.TZ1.S_5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

Find the Cartesian equation of plane Π containing the points \n\nA\n\n\n(\n\n6\n,\n\n \n\n2\n,\n\n \n\n1\n\n)\n\n and \n\nB\n\n\n(\n\n3\n,\n\n \n\n\n1\n,\n\n \n\n1\n\n)\n\n and perpendicular to the plane \nx\n+\n2\ny\n\nz\n\n6\n=\n0\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

\n\n\nAB\n\n\n\n=\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\n3\n\n\n\n\n\n0\n\n\n\n\n)\n\n     (A1)

\n

\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\n3\n\n\n\n\n\n0\n\n\n\n\n)\n\n×\n\n(\n\n\n\n\n1\n\n\n\n\n2\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n     M1A1

\n

\n=\n\n(\n\n\n\n\n3\n\n\n\n\n\n\n3\n\n\n\n\n\n\n\n3\n\n\n\n\n\n)\n\n     A1

\n

\nx\n\ny\n\nz\n=\nk\n     M1

\n

\nk\n=\n3\n equation of plane Π is \nx\n\ny\n\nz\n=\n3\n or equivalent     A1

\n

METHOD 2

\n

let plane Π be \na\nx\n+\nb\ny\n+\nc\nz\n=\nd\n

\n

attempt to form one or more simultaneous equations:     M1

\n

\na\n+\n2\nb\n\nc\n=\n0\n     (1)     A1

\n

\n6\na\n+\n2\nb\n+\nc\n=\nd\n     (2)

\n

\n3\na\n\nb\n+\nc\n=\nd\n     (3)     A1

\n

 

\n

Note:     Award second A1 for equations (2) and (3).

\n

 

\n

attempt to solve     M1

\n

EITHER

\n

using GDC gives \na\n=\n\nd\n3\n\n,\n\n \n\nb\n=\n\n\nd\n3\n\n,\n\n \n\nc\n=\n\n\nd\n3\n\n     (A1)

\n

equation of plane Π is \nx\n\ny\n\nz\n=\n3\n or equivalent     A1

\n

OR

\n

row reduction     M1

\n

equation of plane Π is \nx\n\ny\n\nz\n=\n3\n or equivalent     A1

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.2.AHL.TZ1.H_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-17-vector-equations-of-a-plane" ] }, { "Question": "
\n

The following diagram shows a circle with centre O and radius 40 cm.

\n

\"M17/5/MATME/SP2/ENG/TZ2/01\"

\n

The points A, B and C are on the circumference of the circle and \n\n\nA\n\n\nO\n^\n\n\nC\n\n\n=\n1.9\n\n radians\n\n.

\n
\n

Find the length of arc ABC.

\n
[2]
\n
a.
\n
\n

Find the perimeter of sector OABC.

\n
[2]
\n
b.
\n
\n

Find the area of sector OABC.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct substitution into arc length formula     (A1)

\n

eg\n\n\n\n\n\n\n(\n40\n)\n(\n1.9\n)\n

\n

\n\narc length\n\n=\n76\n\n (cm)\n\n     A1     N2

\n

[2 marks]

\n
a.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\narc\n\n+\n2\nr\n,\n\n \n\n76\n+\n40\n+\n40\n

\n

\n\nperimeter\n\n=\n156\n\n (cm)\n\n     A1     N2

\n

[2 marks]

\n
b.
\n
\n

correct substitution into area formula     (A1)

\n

eg\n\n\n\n\n\n\n\n1\n2\n\n(\n1.9\n)\n\n(\n40\n\n)\n2\n\n\n

\n

\n\narea\n\n=\n1520\n\n (c\n\n\n\n\nm\n\n\n2\n\n\n\n\n)\n\n     A1     N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.SL.TZ2.S_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

The following figure shows a square based pyramid with vertices at O(0, 0, 0), A(1, 0, 0), B(1, 1, 0), C(0, 1, 0) and D(0, 0, 1).

\n

\n
\n

The Cartesian equation of the plane \n\n\nΠ\n2\n\n\n, passing through the points B , C and D , is \ny\n+\nz\n=\n1\n.

\n
\n

The plane \n\n\nΠ\n3\n\n\n passes through O and is normal to the line BD.

\n
\n

\n\n\nΠ\n3\n\n\n cuts AD and BD at the points P and Q respectively.

\n
\n

Find the Cartesian equation of the plane \n\n\nΠ\n1\n\n\n, passing through the points A , B and D.

\n
[3]
\n
a.
\n
\n

Find the angle between the faces ABD and BCD.

\n
[4]
\n
b.
\n
\n

Find the Cartesian equation of \n\n\nΠ\n3\n\n\n.

\n
[3]
\n
c.
\n
\n

Show that P is the midpoint of AD.

\n
[4]
\n
d.
\n
\n

Find the area of the triangle OPQ.

\n
[5]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognising normal to plane or attempting to find cross product of two vectors lying in the plane      (M1)

\n

for example, \n\n\n\nAB\n\n\n\n\n\n\n×\n\n\n\nAD\n\n\n\n\n=\n\n(\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n0\n\n\n\n)\n\n×\n\n(\n\n\n\n\n1\n\n\n\n\n\n0\n\n\n\n\n\n1\n\n\n\n)\n\n=\n\n(\n\n\n\n1\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n)\n\n     (A1)

\n

\n\n\nΠ\n1\n\n\n\n\n:\n\n\n\nx\n+\nz\n=\n1\n     A1

\n

[3 marks]

\n
a.
\n
\n

EITHER

\n

\n\n(\n\n\n\n1\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n)\n\n\n\n(\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n1\n\n\n\n)\n\n=\n1\n=\n\n2\n\n\n2\n\n\n\ncos\n\n\nθ\n     M1A1

\n

OR

\n

\n\n|\n\n\n(\n\n\n\n1\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n)\n\n×\n\n(\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n1\n\n\n\n)\n\n\n|\n\n=\n\n3\n\n=\n\n2\n\n\n2\n\n\n\nsin\n\n\nθ\n     M1A1

\n

Note: M1 is for an attempt to find the scalar or vector product of the two normal vectors.

\n

\n\nθ\n=\n\n60\n\n\n\n(\n\n=\n\nπ\n3\n\n\n)\n\n     A1

\n

angle between faces is \n\n20\n\n\n\n(\n\n=\n\n\n2\nπ\n\n3\n\n\n)\n\n     A1

\n

[4 marks]

\n
b.
\n
\n

\n\n\n\nDB\n\n\n\n\n=\n\n(\n\n\n\n\n1\n\n\n\n\n\n1\n\n\n\n\n\n1\n\n\n\n)\n\n or \n\n\n\nBD\n\n\n\n\n=\n\n(\n\n\n\n\n1\n\n\n\n\n\n1\n\n\n\n\n\n1\n\n\n\n)\n\n     (A1)

\n

\n\n\nΠ\n3\n\n\n\n\n:\n\n\n\nx\n+\ny\n\nz\n=\nk\n     (M1)

\n

\n\n\nΠ\n3\n\n\n\n\n:\n\n\n\nx\n+\ny\n\nz\n=\n0\n     A1

\n

[3 marks]

\n
c.
\n
\n

METHOD 1

\n

line AD : (r =)\n\n(\n\n\n\n0\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n1\n\n\n\n\n\n0\n\n\n\n\n\n1\n\n\n\n)\n\n     M1A1

\n

intersects \n\n\nΠ\n3\n\n\n when \nλ\n\n\n(\n\n1\n\nλ\n\n)\n\n=\n0\n     M1

\n

so \nλ\n=\n\n1\n2\n\n     A1

\n

hence P is the midpoint of AD      AG

\n

 

\n

METHOD 2

\n

midpoint of AD is (0.5, 0, 0.5)      (M1)A1

\n

substitute into \nx\n+\ny\n\nz\n=\n0\n     M1

\n

0.5 + 0.5 − 0.5 = 0     A1

\n

hence P is the midpoint of AD     AG

\n

[4 marks]

\n
d.
\n
\n

METHOD 1

\n

\n\nOP\n\n=\n\n1\n\n\n2\n\n\n\n,\n\n\n\nO\n\n\n\nP\n\n\n\n\n\nQ\n\n=\n\n90\n\n\n,\n\n\n\nO\n\n\n\nQ\n\n\n\n\n\nP\n\n=\n\n60\n\n\n      A1A1A1

\n

\n\nPQ\n\n=\n\n1\n\n\n6\n\n\n\n     A1

\n

area \n=\n\n1\n\n2\n\n12\n\n\n\n=\n\n1\n\n4\n\n3\n\n\n\n=\n\n\n\n3\n\n\n\n12\n\n\n     A1

\n

 

\n

METHOD 2

\n

line BD : ( =)\n\n(\n\n\n\n1\n\n\n\n\n1\n\n\n\n\n0\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n1\n\n\n\n\n\n1\n\n\n\n\n\n1\n\n\n\n)\n\n

\n

\n\nλ\n=\n\n2\n3\n\n     (A1)

\n

\n\n\n\nOQ\n\n\n\n\n=\n\n(\n\n\n\n\n1\n3\n\n\n\n\n\n\n1\n3\n\n\n\n\n\n\n2\n3\n\n\n\n\n)\n\n    A1

\n

area = \n\n1\n2\n\n\n|\n\n\n\n\nOP\n\n\n\n\n\n×\n\n\n\nOQ\n\n\n\n\n\n|\n\n     M1

\n

\n\n\n\nOP\n\n\n\n\n=\n\n(\n\n\n\n\n1\n2\n\n\n\n\n\n0\n\n\n\n\n\n1\n2\n\n\n\n\n)\n\n    A1

\n

Note: This A1 is dependent on M1.

\n

area = \n\n\n\n3\n\n\n\n12\n\n\n     A1

\n

[5 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.1.AHL.TZ1.H_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-17-vector-equations-of-a-plane" ] }, { "Question": "
\n

The following diagram shows a circle, centre O and radius \nr\n mm. The circle is divided into five equal sectors.

\n

\"N16/5/MATME/SP2/ENG/TZ0/03\"

\n

One sector is OAB, and \n\n\nA\n\n\nO\n^\n\n\nB\n\n\n=\nθ\n.

\n
\n

The area of sector AOB is \n20\nπ\n\n m\n\n\n\n\nm\n\n2\n\n\n.

\n
\n

Write down the exact value of θ in radians.

\n
[1]
\n
a.
\n
\n

Find the value of r .

\n
[3]
\n
b.
\n
\n

Find AB.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

θ = 2 π 5      A1     N1

\n

[1 mark]

\n
a.
\n
\n

correct expression for area     (A1)

\n

eg A = 1 2 r 2 ( 2 π 5 ) ,   π r 2 5

\n

evidence of equating their expression to 20 π      (M1)

\n

eg 1 2 r 2 ( 2 π 5 ) = 20 π ,   r 2 = 100 ,   r = ± 10

\n

r = 10    A1     N2

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

evidence of choosing cosine rule     (M1)

\n

eg a 2 = b 2 + c 2 2 b c cos A

\n

correct substitution of their r and θ into RHS     (A1)

\n

eg 10 2 + 10 2 2 × 10 × 1 0 cos ( 2 π 5 )

\n

11.7557

\n

AB = 11.8  (mm)      A1     N2

\n

METHOD 2

\n

evidence of choosing sine rule     (M1)

\n

eg sin A a = sin B b

\n

correct substitution of their r and θ      (A1)

\n

eg sin 2 π 5 AB = sin ( 1 2 ( π 2 π 5 ) ) 10

\n

11.7557

\n

AB = 11.8  (mm)      A1     N2

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.2.SL.TZ0.S_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

The plane П1 contains the points P(1, 6, −7) , Q(0, 1, 1) and R(2, 0, −4).

\n
\n

The Cartesian equation of the plane П2 is given by \nx\n\n3\ny\n\nz\n=\n3\n.

\n
\n

The Cartesian equation of the plane П3 is given by \na\nx\n+\nb\ny\n+\nc\nz\n=\n1\n.

\n
\n

Consider the case that П3 contains \nL\n.

\n
\n

Find the Cartesian equation of the plane containing P, Q and R.

\n
[6]
\n
a.
\n
\n

Given that П1 and П2 meet in a line \nL\n, verify that the vector equation of \nL\n can be given by r \n=\n\n(\n\n\n\n\n\n\n5\n4\n\n\n\n\n\n\n0\n\n\n\n\n\n\n\n7\n4\n\n\n\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n\n\n1\n2\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n5\n2\n\n\n\n\n\n\n)\n\n.

\n
[3]
\n
b.
\n
\n

Given that П3 is parallel to the line \nL\n, show that \na\n+\n2\nb\n\n5\nc\n=\n0\n.

\n
[1]
\n
c.
\n
\n

Show that \n5\na\n\n7\nc\n=\n4\n.

\n
[2]
\n
d.i.
\n
\n

Given that П3 is equally inclined to both П1 and П2, determine two distinct possible Cartesian equations for П3.

\n
[7]
\n
d.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

for example

\n

\n\n\nPQ\n\n\n\n=\n\n(\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n5\n\n\n\n\n\n8\n\n\n\n\n)\n\n\n\n\nPR\n\n\n\n=\n\n(\n\n\n\n\n1\n\n\n\n\n\n\n6\n\n\n\n\n\n3\n\n\n\n\n)\n\n       A1A1

\n

\n\n\nPQ\n\n\n\n×\n\n\nPR\n\n\n\n = 33i + 11j + 11k      (M1)A1

\n

r.n = a.n

\n

\n33\nx\n+\n11\ny\n+\n11\nz\n=\n\n(\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n1\n\n\n\n\n)\n\n\n\n(\n\n\n\n\n\n33\n\n\n\n\n\n\n11\n\n\n\n\n\n\n11\n\n\n\n\n\n)\n\n=\n22\n     (M1)

\n

\n\n3\nx\n+\ny\n+\nz\n=\n2\n or equivalent       A1

\n

 

\n

METHOD 2

\n

assume plane can be written as \na\nx\n+\nb\ny\n+\nc\nz\n=\n1\n       M1

\n

substituting each set of coordinates gives the system of equations:

\n

\na\n+\n6\nb\n\n7\nc\n=\n1\n

\n

\n0\na\n+\nb\n+\nc\n=\n1\n

\n

\n2\na\n+\n0\nb\n\n4\nc\n=\n1\n       A1

\n

solving by GDC      (M1)

\n

\na\n=\n\n3\n2\n\n\nb\n=\n\n1\n2\n\n\nC\n=\n\n1\n2\n\n       A1A1A1

\n

\n\n\n3\n2\n\nx\n+\n\n1\n2\n\ny\n+\n\n1\n2\n\nz\n=\n1\n or equivalent

\n

 

\n

[6 marks]

\n
a.
\n
\n

METHOD 1

\n

substitution of equation of line into both equations of planes       M1

\n

\n3\n\n(\n\n\n5\n4\n\n+\n\nλ\n2\n\n\n)\n\n+\n\n(\n\n\n\n7\n4\n\n\n\n\n5\nλ\n\n2\n\n\n)\n\n=\n2\n       A1

\n

\n\n(\n\n\n5\n4\n\n+\n\nλ\n2\n\n\n)\n\n\n3\nλ\n\n\n(\n\n\n\n7\n4\n\n\n\n\n5\nλ\n\n2\n\n\n)\n\n=\n3\n       A1

\n

 

\n

METHOD 2

\n

adding Π1 and Π2 gives \n4\nx\n\n2\ny\n=\n5\n       M1

\n

given  \ny\n=\nλ\n\nx\n=\n\n5\n4\n\n+\n\nλ\n2\n\n       A1

\n

\nz\n=\n2\n\ny\n\n3\nx\n=\n\n\n7\n4\n\n\n\n\n5\nλ\n\n2\n\n       A1

\n

r \n=\n\n(\n\n\n\n\n\n\n5\n4\n\n\n\n\n\n\n0\n\n\n\n\n\n\n\n7\n4\n\n\n\n\n\n\n)\n\n+\nλ\n\n(\n\n\n\n\n\n\n1\n2\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n5\n2\n\n\n\n\n\n\n)\n\n       AG

\n

 

\n

METHOD 3

\n

n1 × n2\n\n(\n\n\n\n\n2\n\n\n\n\n4\n\n\n\n\n\n\n10\n\n\n\n\n\n)\n\n       A1

\n

\n=\n4\n\n(\n\n\n\n\n\n\n1\n2\n\n\n\n\n\n\n1\n\n\n\n\n\n\n\n5\n2\n\n\n\n\n\n\n)\n\n       R1

\n

common point \n\n5\n4\n\n\n3\n\n(\n0\n)\n\n\n\n(\n\n\n\n7\n4\n\n\n)\n\n=\n3\n and \n\n3\n\n(\n\n\n5\n4\n\n\n)\n\n\n0\n\n\n(\n\n\n\n7\n4\n\n\n)\n\n=\n\n2\n       A1 

\n

 

\n

[3 marks]

\n
b.
\n
\n

normal to П3 is perpendicular to direction of \nL\n

\n

\n\n\n(\n\n\n\n\na\n\n\n\n\nb\n\n\n\n\nc\n\n\n\n\n)\n\n\n\n(\n\n\n\n\n1\n\n\n\n\n2\n\n\n\n\n\n\n5\n\n\n\n\n\n)\n\n=\n0\n       A1

\n

\na\n+\n2\nb\n\n5\nc\n=\n0\n       AG

\n

[1 mark]

\n
c.
\n
\n

substituting \n\n(\n\n\n\n\n\n\n5\n4\n\n\n\n\n\n\n0\n\n\n\n\n\n\n\n7\n4\n\n\n\n\n\n\n)\n\n into П3:      M1

\n

\n\n\n5\na\n\n4\n\n\n\n\n7\nc\n\n4\n\n=\n1\n      A1

\n

\n5\na\n\n7\nc\n=\n4\n      AG

\n

[2 marks]

\n
d.i.
\n
\n

attempt to find scalar products for П1 and П3П2 and П3.

\n

and equating       M1

\n

\n\n\n3\na\n+\nb\n+\nC\n\n\n\n11\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n+\n\n\nc\n2\n\n\n\n\n\n=\n\n\na\n\n3\nb\n\nc\n\n\n\n11\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n+\n\n\nc\n2\n\n\n\n\n\n      M1

\n

Note: Accept \n3\na\n+\nb\n+\nc\n=\na\n\n3\nb\n\nc\n.

\n

\n\na\n+\n2\nb\n+\nc\n=\n0\n      A1

\n

attempt to solve \na\n+\n2\nb\n+\nc\n=\n0\n\na\n+\n2\nb\n\n5\nc\n=\n0\n\n5\na\n\n7\nc\n=\n4\n      M1

\n

\n\na\n=\n\n4\n5\n\n\n,\n\n\n\nb\n=\n\n\n2\n5\n\n\n,\n\n\n\nc\n=\n0\n      A1

\n

hence equation is \n\n\n4\nx\n\n5\n\n\n\n\n2\ny\n\n5\n\n=\n1\n

\n

for second equation:

\n

\n\n\n3\na\n+\nb\n+\nC\n\n\n\n11\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n+\n\n\nc\n2\n\n\n\n\n\n=\n\n\n\na\n\n3\nb\n\nc\n\n\n\n11\n\n\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n+\n\n\nc\n2\n\n\n\n\n\n      (M1)

\n

\n\n2\na\n\nb\n=\n0\n

\n

attempt to solve \n2\na\n\nb\n=\n0\n\na\n+\n2\nb\n\n5\nc\n=\n0\n\n5\na\n\n7\nc\n=\n4\n      M1

\n

\na\n=\n\n2\n\nb\n=\n\n4\n\nc\n=\n\n2\n      A1

\n

hence equation is \n\n2\nx\n\n4\ny\n\n2\nz\n=\n1\n

\n

[7 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "19M.2.AHL.TZ2.H_11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-17-vector-equations-of-a-plane" ] }, { "Question": "
\n

The diagram shows a circle, centre O, with radius 4 cm. Points A and B lie on the circumference of the circle and AÔB = θ , where 0 ≤ θ\nπ\n.

\n

\n
\n

Find the area of the shaded region, in terms of θ.

\n
[3]
\n
a.
\n
\n

The area of the shaded region is 12 cm2. Find the value of θ.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach to find area of segment      (M1)

\n

eg  area of sector – area of triangle, \n\n1\n2\n\n\n\nr\n2\n\n\n\n(\n\nθ\n\n\nsin\n\nθ\n\n)\n\n

\n

correct substitution      (A1)

\n

eg  \n\n1\n4\n\n\n\n\n(\n4\n)\n\n2\n\n\nθ\n\n\n1\n2\n\n\n\n\n(\n4\n)\n\n2\n\n\n\nsin\n\nθ\n,\n\n\n\n1\n2\n\n×\n16\n\n[\n\nθ\n\n\nsin\n\nθ\n\n]\n\n

\n

area = 80 – 8 sinθ, 8(θ – sinθ)     A1 N2

\n

[3 marks]

\n
a.
\n
\n

setting their area expression equal to 12      (M1)

\n

eg  12 = 8(θ – sinθ)    

\n

2.26717

\n

θ = 2.27 (do not accept an answer in degrees)      A2 N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.SL.TZ1.S_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

The following diagram shows a right triangle ABC. Point D lies on AB such that CD bisects AĈB.

\n

\n

AĈD = θ and AC = 14 cm

\n
\n

Given that  sin θ = 3 5 , find the value of  cos θ .

\n
[3]
\n
a.
\n
\n

Find the value of  cos 2 θ .

\n
[3]
\n
b.
\n
\n

Hence or otherwise, find BC .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

valid approach       (M1)

\n

eg      labelled sides on separate triangle,  si n 2 x + co s 2 x = 1

\n

correct working       (A1)

\n

eg      missing side is 4,  1 ( 3 5 ) 2

\n

cos θ = 4 5                           A1   N3

\n

[3 marks]

\n
a.
\n
\n

correct substitution into  cos 2 θ        (A1)

\n

eg      2 ( 16 25 ) 1 ,   1 2 ( 3 5 ) 2 ,   16 25 9 25

\n

cos 2 θ = 7 25                          A1   N2

\n

[2 marks]

\n
b.
\n
\n

correct working      (A1)

\n

eg      7 25 = 14 BC BC = 14 × 25 7

\n

BC = 50  (cm)                        A1   N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ1.S_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The following diagram shows a circle with centre O and radius r cm.

\n

\n

The points A and B lie on the circumference of the circle, and \n\nA\n\n\n\nO\n\n\n\n\n\nB\n\n = θ. The area of the shaded sector AOB is 12 cm2 and the length of arc AB is 6 cm.

\n

Find the value of r.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of correctly substituting into circle formula (may be seen later)      A1A1
eg  \n\n1\n2\n\nθ\n\n\nr\n2\n\n\n=\n12\n,\n\n\nr\nθ\n=\n6\n

\n

attempt to eliminate one variable      (M1)
eg  \nr\n=\n\n6\nθ\n\n,\n\n\nθ\n=\n\n1\nr\n\n,\n\n\n\n\n\n1\n2\n\nθ\n\n\nr\n2\n\n\n\n\nr\nθ\n\n\n=\n\n\n12\n\n6\n\n

\n

correct elimination      (A1)
eg  \n\n1\n2\n\n×\n\n6\nr\n\n×\n\n\nr\n2\n\n\n=\n12\n,\n\n\n\n1\n2\n\nθ\n×\n\n\n\n(\n\n\n6\nθ\n\n\n)\n\n2\n\n\n=\n12\n,\n\n\nA\n=\n\n1\n2\n\n×\n\n\nr\n2\n\n\n×\n\nl\nr\n\n,\n\n\n\n\n\n\nr\n2\n\n\n\n\n2\nr\n\n\n=\n2\n

\n

correct equation     (A1)
eg  \n\n1\n2\n\n×\n6\nr\n=\n12\n,\n\n\n\n1\n2\n\n×\n\n\n36\n\nθ\n\n=\n12\n,\n\n\n12\n=\n\n1\n2\n\n×\n\n\nr\n2\n\n\n×\n\n6\nr\n\n

\n

correct working      (A1)
eg  \n3\nr\n=\n12\n,\n\n\n\n\n18\n\nθ\n\n=\n12\n,\n\n\n\nr\n2\n\n=\n2\n,\n\n\n24\n=\n6\nr\n

\n

r = 4 (cm)      A1 N2

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.SL.TZ2.S_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

Six equilateral triangles, each with side length 3 cm, are arranged to form a hexagon.
This is shown in the following diagram.

\n

\n

The vectors p , q and r are shown on the diagram.

\n

Find p•(p + q + r).

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1 (using |p| |2q| cosθ)

\n

finding p + q + r      (A1)

\n

eg  2q

\n

p + q + | = 2 × 3 (= 6)  (seen anywhere)     A1

\n

correct angle between p and q (seen anywhere)      (A1)

\n

π 3   (accept 60°)

\n

substitution of their values     (M1)

\n

eg  3 × 6 × cos ( π 3 )

\n

correct value for cos ( π 3 )  (seen anywhere)     (A1)

\n

eg   1 2 , 3 × 6 × 1 2

\n

p•(p + q + r) = 9     A1 N3

\n

 

\n

METHOD 2 (scalar product using distributive law)

\n

correct expression for scalar distribution      (A1)

\n

eg  p• p + pq + pr

\n

three correct angles between the vector pairs (seen anywhere)      (A2)

\n

eg  0° between p and p π 3 between p and q 2 π 3 between p and r

\n

Note: Award A1 for only two correct angles.

\n

substitution of their values      (M1)

\n

eg  3.3.cos0 +3.3.cos π 3 + 3.3.cos120

\n

one correct value for cos0, cos ( π 3 ) or cos ( 2 π 3 )  (seen anywhere)      A1

\n

eg   1 2 , 3 × 6 × 1 2

\n

p•(p + q + r) = 9     A1 N3

\n

 

\n

METHOD 3 (scalar product using relative position vectors)

\n

valid attempt to find one component of p or r      (M1)

\n

eg   sin 60 =  x 3 , cos 60 =  x 3 , one correct value  3 2 , 3 3 2 , 3 3 2

\n

one correct vector (two or three dimensions) (seen anywhere)      A1

\n

eg  p = ( 3 2 3 3 2 ) , q = ( 3 0 ) , r = ( 3 2 3 3 2 0 )

\n

three correct vectors p + q + = 2q     (A1)

\n

p + q +  ( 6 0 ) or  ( 6 0 0 )  (seen anywhere, including scalar product)      (A1)

\n

correct working       (A1)
eg   ( 3 2 × 6 ) + ( 3 3 2 × 0 ) , 9 + 0 + 0

\n

p•(p + q + r) = 9     A1 N3

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.SL.TZ1.S_6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

Find the coordinates of the point of intersection of the planes defined by the equations x + y + z = 3 ,   x y + z = 5 and x + y + 2 z = 6 .

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1

\n

for eliminating one variable from two equations     (M1)

\n

eg, { ( x + y + z = 3 ) 2 x + 2 z = 8 2 x + 3 z = 11      A1A1

\n

for finding correctly one coordinate

\n

eg, { ( x + y + z = 3 ) ( 2 x + 2 z = 8 ) z = 3      A1

\n

for finding correctly the other two coordinates     A1

\n

{ x = 1 y = 1 z = 3

\n

the intersection point has coordinates  ( 1 ,   1 ,   3 )

\n

METHOD 2

\n

for eliminating two variables from two equations or using row reduction     (M1)

\n

eg, { ( x + y + z = 3 ) 2 = 2 z = 3  or  ( 1 1 1 0 2 0 0 0 1 | 3 2 3 )      A1A1

\n

for finding correctly the other coordinates     A1A1

\n

{ x = 1 y = 1 ( z = 3 )  or  ( 1 0 0 0 1 0 0 0 1 | 1 1 3 )

\n

the intersection point has coordinates  ( 1 ,   1 ,   3 )

\n

METHOD 3

\n

| 1 1 1 1 1 1 1 1 2 | = 2    (A1)

\n

attempt to use Cramer’s rule     M1

\n

x = | 3 1 1 5 1 1 6 1 2 | 2 = 2 2 = 1    A1

\n

y = | 1 3 1 1 5 1 1 6 2 | 2 = 2 2 = 1    A1

\n

z = | 1 1 3 1 1 5 1 1 6 | 2 = 6 2 = 3    A1

\n

 

\n

Note:     Award M1 only if candidate attempts to determine at least one of the variables using this method.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.1.AHL.TZ0.H_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-18-intersections-of-lines-&-planes" ] }, { "Question": "
\n

The discrete random variable X has the following probability distribution, where p is a constant.

\n

\n
\n

Find the value of p.

\n
[2]
\n
a.
\n
\n

Find μ, the expected value of X.

\n
[2]
\n
b.i.
\n
\n

Find P(X > μ).

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

equating sum of probabilities to 1 (p + 0.5 − p + 0.25 + 0.125 + p3 = 1)       M1

\n

p3 = 0.125 =  1 8

\n

p= 0.5      A1

\n

[2 marks]

\n
a.
\n
\n

μ = 0 × 0.5 + 1 × 0 + 2 × 0.25 + 3 × 0.125 + 4 × 0.125       M1

\n

= 1.375  ( = 11 8 )      A1

\n

[2 marks]

\n
b.i.
\n
\n

P(X > μ) = P(X = 2) + P(X = 3) + P(X = 4)      (M1)

\n

= 0.5       A1

\n

Note: Do not award follow through A marks in (b)(i) from an incorrect value of p.

\n

Note: Award M marks in both (b)(i) and (b)(ii) provided no negative probabilities, and provided a numerical value for μ has been found.

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18M.1.AHL.TZ2.H_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

The magnitudes of two vectors, u and v, are 4 and  3  respectively. The angle between u and v is  π 6 .

\n

Let w = u − v. Find the magnitude of w.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1 (cosine rule)

\n

diagram including u, v and included angle of  π 6       (M1)

\n

eg   

\n

sketch of triangle with w (does not need to be to scale)      (A1)

\n

eg  

\n

choosing cosine rule      (M1)

\n

eg     a 2 + b 2 2 a b cos C

\n

correct substitution        A1

\n

eg    4 2 + ( 3 ) 2 2 ( 4 ) ( 3 ) cos π 6

\n

cos π 6 = 3 2  (seen anywhere)       (A1)

\n

correct working        (A1)

\n

eg    16 + 3 − 12

\n

| w | =  7         A1    N2

\n

 

\n

METHOD 2 (scalar product)

\n

valid approach, in terms of u and v (seen anywhere)      (M1)

\n

eg   | w |2 = (u − v)•(u − v), | w |2 = u− 2uvv, | w |= ( u 1 v 1 ) 2 + ( u 2 v 2 ) 2 ,

\n

| w | =  ( u 1 v 1 ) 2 + ( u 2 v 2 ) 2 + ( u 3 v 3 ) 2

\n

correct value for uu (seen anywhere)       (A1)

\n

eg   | u|2 = 16,  uu = 16,  u 1 2 + u 2 2 = 16

\n

correct value for vv (seen anywhere)      (A1)

\n

eg  | v|2 = 16,  vv = 3,  v 1 2 + v 2 2 + v 3 2 = 3

\n

cos ( π 6 ) = 3 2   (seen anywhere)      (A1)

\n

uv  = 4 × 3 × 3 2   (= 6)  (seen anywhere)       A1

\n

correct substitution into u− 2uvv or u 1 2 + u 2 2 + v 1 2 + v 2 2 2 ( u 1 v 1 + u 2 v 2 )   (2 or 3 dimensions)      (A1)

\n

eg   16 − 2(6) + 3  (= 7)

\n

| w | =  7         A1    N2

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.SL.TZ1.S_6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

Show that sin2x+cos2x-1=2sinxcosx-sinx.

\n
[2]
\n
a.
\n
\n

Hence or otherwise, solve sin2x+cos2x-1+cosx-sinx=0 for 0<x<2π.

\n

 

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

Note: Do not award the final A1 for proofs which work from both sides to find a common expression other than 2sinxcosx-2sin2x.

\n

 

\n

METHOD 1 (LHS to RHS)

\n

attempt to use double angle formula for sin2x or cos2x          M1

\n

LHS =2sinxcosx+cos2x-1  OR

\n

sin2x+1-2sin2x-1  OR

\n

2sinxcosx+1-2sin2x-1

\n

=2sinxcosx-2sin2x          A1

\n

sin2x+cos2x-1=2sinxcosx-sinx= RHS          AG

\n

 

\n

METHOD 2 (RHS to LHS)

\n

RHS =2sinxcosx-2sin2x

\n

       attempt to use double angle formula for sin2x or cos2x          M1

\n

       =sin2x+1-2sin2x-1          A1

\n

       =sin2x+cos2x-1= LHS          AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

attempt to factorise          M1

\n

cosx-sinx2sinx+1=0          A1

\n

recognition of cosx=sinxsinxcosx=tanx=1  OR  sinx=-12        (M1)

\n

one correct reference angle seen anywhere, accept degrees        (A1)

\n

π4  OR  π6 (accept -π6,7π6)

\n

 

\n

Note: This (M1)(A1) is independent of the previous M1A1.

\n

 

\n

x=7π6,11π6,π4,5π4          A2

\n

 

\n

Note: Award A1 for any two correct (radian) answers.
Award A1A0 if additional values given with the four correct (radian) answers.
Award A1A0 for four correct answers given in degrees.

\n

 

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.SL.TZ1.6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-6-pythagorean-identity-double-angles" ] }, { "Question": "
\n

Let \nθ\n be an obtuse angle such that \n\nsin\n\n\nθ\n=\n\n3\n5\n\n.

\n
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n\ne\n\nx\n\n\n\n\nsin\n\n\nx\n\n\n\n3\nx\n\n4\n\n.

\n
\n

Find the value of tan θ .

\n
[4]
\n
a.
\n
\n

Line L passes through the origin and has a gradient of tan θ . Find the equation of L .

\n
[2]
\n
b.
\n
\n

The following diagram shows the graph of f  for 0 ≤ x ≤ 3. Line M is a tangent to the graph of f at point P.

\n

\n

Given that M is parallel to L , find the x -coordinate of P.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of valid approach       (M1)

\n

eg   sketch of triangle with sides 3 and 5,  co s 2 θ = 1 si n 2 θ

\n

correct working       (A1)

\n

eg  missing side is 4 (may be seen in sketch),  cos θ = 4 5 ,   cos θ = 4 5

\n

tan θ = 3 4        A2 N4

\n

[4 marks]

\n
a.
\n
\n

correct substitution of either gradient or origin into equation of line        (A1)

\n

(do not accept y = m x + b )

\n

eg    y = x tan θ ,    y 0 = m ( x 0 ) ,    y = m x

\n

y = 3 4 x      A2 N4

\n

Note: Award A1A0 for  L = 3 4 x .

\n

[2 marks]

\n
b.
\n
\n

valid approach to equate their gradients       (M1)

\n

eg    f = tan θ ,    f = 3 4 e x cos x + e x sin x 3 4 = 3 4 ,    e x ( cos x + sin x ) 3 4 = 3 4

\n

correct equation without  e x         (A1)

\n

eg    sin x = cos x ,   cos x + sin x = 0 ,   sin x cos x = 1

\n

correct working       (A1)

\n

eg    tan θ = 1 ,   x = 135

\n

x = 3 π 4 (do not accept  135 )       A1 N1

\n

Note: Do not award the final A1 if additional answers are given.

\n

[4 marks]

\n

 

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.1.SL.TZ2.S_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Let fx=mx2-2mx, where x and m. The line y=mx-9 meets the graph of f at exactly one point.

\n
\n

The function f can be expressed in the form fx=4x-px-q, where p,q.

\n
\n

The function f can also be expressed in the form fx=4x-h2+k, where h,k.

\n
\n

Show that m=4.

\n
[6]
\n
a.
\n
\n

Find the value of p and the value of q.

\n
[2]
\n
b.
\n
\n

Find the value of h and the value of k.

\n
[3]
\n
c.
\n
\n

Hence find the values of x where the graph of f is both negative and increasing.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

METHOD 1 (discriminant)

\n

mx2-2mx=mx-9        (M1)

\n

mx2-3mx+9=0

\n

recognizing Δ=0 (seen anywhere)        M1

\n

Δ=-3m2-4m9  (do not accept only in quadratic formula for x)          A1

\n

valid approach to solve quadratic for m        (M1)

\n

9mm-4=0  OR  m=36±362-4×9×02×9

\n

both solutions m=0,4          A1

\n

m0 with a valid reason          R1

\n

the two graphs would not intersect OR 0-9

\n

m=4          AG

\n

 

\n

METHOD 2 (equating slopes)

\n

mx2-2mx=mx-9  (seen anywhere)        (M1)

\n

f'x=2mx-2m          A1

\n

equating slopes, f'x=m  (seen anywhere)          M1

\n

2mx-2m=m

\n

x=32          A1

\n

substituting their x value        (M1)

\n

322m-2m×32=m×32-9

\n

94m-124m=64m-9          A1

\n

-9m4=-9

\n

m=4         AG

\n

 

\n

METHOD 3 (using -b2a)

\n

mx2-2mx=mx-9        (M1)

\n

mx2-3mx+9=0

\n

attempt to find x-coord of vertex using -b2a        (M1)

\n

--3m2m          A1

\n

x=32          A1

\n

substituting their x value        (M1)

\n

322m-3m×32+9=0

\n

94m-92m+9=0          A1

\n

-9m=-36

\n

m=4         AG

\n

 

\n

[6 marks]

\n
a.
\n
\n

4xx-2        (A1)

\n

p=0 and q=2  OR  p=2 and q=0         A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

attempt to use valid approach        (M1)

\n

0+22, --82×4, f1, 8x-8=0  OR  4x2-2x+1-1=4x-12-4

\n

h=1, k=-4         A1A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

EITHER

\n

recognition x=h to 2 (may be seen on sketch)        (M1)

\n

 

\n

OR

\n

recognition that fx<0 and f'x>0        (M1)

\n

 

\n

THEN

\n

1<x<2         A1A1

\n

 

\n

Note: Award A1 for two correct values, A1 for correct inequality signs.

\n

 

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21M.1.SL.TZ1.7", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-6-quadratic-function" ] }, { "Question": "
\n

Let y=lnxx4 for x>0.

\n
\n

Consider the function defined by fxlnxx4 for x>0 and its graph y=fx.

\n
\n

Show that dydx=1-4lnxx5.

\n
[3]
\n
a.
\n
\n

The graph of f has a horizontal tangent at point P. Find the coordinates of P.

\n
[5]
\n
b.
\n
\n

Given that f''x=20lnx-9x6, show that P is a local maximum point.

\n
[3]
\n
c.
\n
\n

Solve fx>0 for x>0.

\n
[2]
\n
d.
\n
\n

Sketch the graph of f, showing clearly the value of the x-intercept and the approximate position of point P.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

attempt to use quotient or product rule        (M1)

\n

dydx=x41x-lnx4x3x42  OR  lnx-4x-5+x-41x         A1

\n

correct working         A1

\n

=x31-4lnxx8  OR  cancelling x3  OR  -4lnxx5+1x5

\n

=1-4lnxx5         AG

\n

 

\n

[3 marks]

\n
a.
\n
\n

f'x=dydx=0        (M1)

\n

1-4lnxx5=0

\n

lnx=14        (A1)

\n

x=e14         A1

\n

substitution of their x to find y        (M1)

\n

y=lne14e144

\n

=14e=14e-1         A1

\n

Pe14,14e

\n

 

\n

[5 marks]

\n
b.
\n
\n

f''e14=20lne14-9e146        (M1)

\n

=5-9e1.5  =-4e1.5         A1

\n

which is negative         R1

\n

hence P is a local maximum         AG

\n

 

\n

Note: The R1 is dependent on the previous A1 being awarded.

\n

 

\n

[3 marks]

\n
c.
\n
\n

lnx>0        (A1)

\n

x>1        A1

\n

 

\n

[2 marks]

\n
d.
\n
\n

        A1A1A1

\n

 

\n

 

\n

Note: Award A1 for one x-intercept only, located at 1

\n

     A1 for local maximum, P, in approximately correct position
     A1 for curve approaching x-axis as x (including change in concavity).

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.1.SL.TZ1.8", "topics": [ "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion", "sl-2-3-graphing", "sl-2-9-exponential-and-logarithmic-functions" ] }, { "Question": "
\n

Let f ( x ) = 15 x 2 , for x R . The following diagram shows part of the graph of f and the rectangle OABC, where A is on the negative x -axis, B is on the graph of f , and C is on the y -axis.

\n

\"N17/5/MATME/SP1/ENG/TZ0/06\"

\n

Find the x -coordinate of A that gives the maximum area of OABC.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

attempt to find the area of OABC     (M1)

\n

eg OA × OC,  x × f ( x ) ,   f ( x ) × ( x )

\n

correct expression for area in one variable     (A1)

\n

eg area = x ( 15 x 2 ) ,   15 x x 3 ,   x 3 15 x

\n

valid approach to find maximum area (seen anywhere)     (M1)

\n

eg A ( x ) = 0

\n

correct derivative     A1

\n

eg 15 3 x 2 ,   ( 15 x 2 ) + x ( 2 x ) = 0 ,   15 + 3 x 2

\n

correct working     (A1)

\n

eg 15 = 3 x 2 ,   x 2 = 5 ,   x = 5

\n

x = 5   ( accept A ( 5 ,   0 ) )     A2     N3

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.SL.TZ0.S_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

Let \nsin\n\nθ\n=\n\n\n\n5\n\n\n3\n\n, where \nθ\n is acute.

\n
\n

Find \ncos\n\nθ\n.

\n
[3]
\n
a.
\n
\n

Find \ncos\n\n2\nθ\n.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of valid approach     (M1)

\n

eg\n\n\n\n\n\nright triangle, \n\n\ncos\n2\n\n\nθ\n=\n1\n\n\n\nsin\n2\n\n\nθ\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\nmissing side is 2, \n\n1\n\n\n\n\n\n(\n\n\n\n\n5\n\n\n3\n\n\n)\n\n\n2\n\n\n\n

\n

\ncos\n\nθ\n=\n\n2\n3\n\n     A1     N2

\n

[3 marks]

\n
a.
\n
\n

correct substitution into formula for \ncos\n\n2\nθ\n     (A1)

\n

eg\n\n\n\n\n\n\n2\n×\n\n\n\n(\n\n\n2\n3\n\n\n)\n\n2\n\n\n\n1\n,\n\n \n\n1\n\n2\n\n\n\n(\n\n\n\n\n5\n\n\n3\n\n\n)\n\n2\n\n\n,\n\n \n\n\n\n\n(\n\n\n2\n3\n\n\n)\n\n2\n\n\n\n\n\n\n(\n\n\n\n\n5\n\n\n3\n\n\n)\n\n2\n\n\n

\n

\ncos\n\n2\nθ\n=\n\n\n1\n9\n\n    A1     N2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.S_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-6-pythagorean-identity-double-angles" ] }, { "Question": "
\n

Note: In this question, distance is in millimetres.

\n

Let \nf\n(\nx\n)\n=\nx\n+\na\nsin\n\n\n(\n\nx\n\n\nπ\n2\n\n\n)\n\n+\na\n, for \nx\n\n0\n.

\n
\n

The graph of \nf\n passes through the origin. Let \n\n\n\nP\n\nk\n\n\n be any point on the graph of \nf\n with \nx\n-coordinate \n2\nk\nπ\n, where \nk\n\n\nN\n\n. A straight line \nL\n passes through all the points \n\n\n\nP\n\nk\n\n\n.

\n
\n

Diagram 1 shows a saw. The length of the toothed edge is the distance AB.

\n

\"N17/5/MATME/SP2/ENG/TZ0/10.d_01\"

\n

The toothed edge of the saw can be modelled using the graph of \nf\n and the line \nL\n. Diagram 2 represents this model.

\n

\"N17/5/MATME/SP2/ENG/TZ0/10.d_02\"

\n

The shaded part on the graph is called a tooth. A tooth is represented by the region enclosed by the graph of \nf\n and the line \nL\n, between \n\n\n\nP\n\nk\n\n\n and \n\n\n\nP\n\n\nk\n+\n1\n\n\n\n.

\n
\n

Show that \nf\n(\n2\nπ\n)\n=\n2\nπ\n.

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[3]
\n
a.
\n
\n

Find the coordinates of \n\n\n\nP\n\n0\n\n\n and of \n\n\n\nP\n\n1\n\n\n.

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[3]
\n
b.i.
\n
\n

Find the equation of \nL\n.

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[3]
\n
b.ii.
\n
\n

Show that the distance between the \nx\n-coordinates of \n\n\n\nP\n\nk\n\n\n and \n\n\n\nP\n\n\nk\n+\n1\n\n\n\n is \n2\nπ\n.

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[2]
\n
c.
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A saw has a toothed edge which is 300 mm long. Find the number of complete teeth on this saw.

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[6]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

substituting \nx\n=\n2\nπ\n     M1

\n

eg\n\n\n\n\n\n\n2\nπ\n+\na\nsin\n\n\n(\n\n2\nπ\n\n\nπ\n2\n\n\n)\n\n+\na\n

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\n2\nπ\n+\na\nsin\n\n\n(\n\n\n\n3\nπ\n\n2\n\n\n)\n\n+\na\n     (A1)

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\n2\nπ\n\na\n+\na\n     A1

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\nf\n(\n2\nπ\n)\n=\n2\nπ\n     AG     N0

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[3 marks]

\n
a.
\n
\n

substituting the value of \nk\n     (M1)

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\n\n\n\nP\n\n0\n\n\n(\n0\n,\n\n \n\n0\n)\n,\n\n \n\n\n\n\nP\n\n1\n\n\n(\n2\nπ\n,\n\n \n\n2\nπ\n)\n     A1A1     N3

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[3 marks]

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b.i.
\n
\n

attempt to find the gradient     (M1)

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eg\n\n\n\n\n\n\n\n\n2\nπ\n\n0\n\n\n2\nπ\n\n0\n\n\n,\n\n \n\nm\n=\n1\n

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correct working     (A1)

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eg\n\n\n\n\n\n\n\n\ny\n\n2\nπ\n\n\nx\n\n2\nπ\n\n\n=\n1\n,\n\n \n\nb\n=\n0\n,\n\n \n\ny\n\n0\n=\n1\n(\nx\n\n0\n)\n

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y = x     A1     N3

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[3 marks]

\n
b.ii.
\n
\n

subtracting \nx\n-coordinates of \n\n\n\nP\n\n\nk\n+\n1\n\n\n\n and \n\n\n\nP\n\nk\n\n\n (in any order)     (M1)

\n

eg\n\n\n\n\n\n\n2\n(\nk\n+\n1\n)\nπ\n\n2\nk\nπ\n,\n\n \n\n2\nk\nπ\n\n2\nk\nπ\n\n2\nπ\n

\n

correct working (must be in correct order)     A1

\n

eg\n\n\n\n\n\n\n2\nk\nπ\n+\n2\nπ\n\n2\nk\nπ\n,\n\n \n\n\n|\n\n2\nk\nπ\n\n2\n(\nk\n+\n1\n)\nπ\n\n|\n\n

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distance is \n2\nπ\n     AG     N0

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[2 marks]

\n
c.
\n
\n

METHOD 1

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recognizing the toothed-edge as the hypotenuse     (M1)

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eg\n\n\n\n\n\n\n\n\n300\n2\n\n\n=\n\n\nx\n2\n\n\n+\n\n\ny\n2\n\n\n, sketch

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correct working (using their equation of \nL\n     (A1)

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eg\n\n\n\n\n\n\n\n\n300\n2\n\n\n=\n\n\nx\n2\n\n\n+\n\n\nx\n2\n\n\n

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\nx\n=\n\n\n300\n\n\n\n2\n\n\n\n (exact), 212.132     (A1)

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dividing their value of \nx\n by \n2\nπ\n\n \n\n\n(\n\n\ndo not accept \n\n\n\n300\n\n\n2\nπ\n\n\n\n)\n\n     (M1)

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eg\n\n\n\n\n\n\n\n\n212.132\n\n\n2\nπ\n\n\n

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33.7618     (A1)

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33 (teeth)     A1     N2

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METHOD 2

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vertical distance of a tooth is \n2\nπ\n (may be seen anywhere)     (A1)

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attempt to find the hypotenuse for one tooth     (M1)

\n

eg\n\n\n\n\n\n\n\n\nx\n2\n\n\n=\n\n(\n2\nπ\n\n)\n2\n\n\n+\n\n(\n2\nπ\n\n)\n2\n\n\n

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\nx\n=\n\n8\n\n\nπ\n2\n\n\n\n (exact), 8.88576     (A1)

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dividing 300 by their value of \nx\n     (M1)

\n

eg

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33.7618     (A1)

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33 (teeth)     A1     N2

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17N.2.SL.TZ0.S_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

Given that \n\nsin\n\n\nx\n=\n\n1\n3\n\n, where \n0\n<\nx\n<\n\nπ\n2\n\n, find the value of \n\ncos\n\n\n4\nx\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

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correct substitution into formula for \n\ncos\n\n\n\n(\n\n2\nx\n\n)\n\n or \n\nsin\n\n\n\n(\n\n2\nx\n\n)\n\n      (A1)

\n

eg   \n1\n\n2\n\n\n\n(\n\n\n1\n3\n\n\n)\n\n2\n\n\n,  \n2\n\n\n\n(\n\n\n\n\n8\n\n\n3\n\n\n)\n\n2\n\n\n\n1\n,  \n2\n\n(\n\n\n1\n3\n\n\n)\n\n\n(\n\n\n\n\n8\n\n\n3\n\n\n)\n\n,  \n\n\n\n(\n\n\n\n\n8\n\n\n3\n\n\n)\n\n2\n\n\n\n\n\n\n(\n\n\n1\n3\n\n\n)\n\n2\n\n\n

\n

\n\ncos\n\n\n\n(\n\n2\nx\n\n)\n\n=\n\n7\n9\n\n  or  \n\nsin\n\n\n\n(\n\n2\nx\n\n)\n\n=\n\n\n2\n\n8\n\n\n9\n\n\n\n\n\n\n(\n\n=\n\n\n\n32\n\n\n9\n\n=\n\n\n4\n\n2\n\n\n9\n\n\n)\n\n  (may be seen in substitution)     A2

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recognizing 4\nx\n is double angle of 2\nx\n (seen anywhere)      (M1)

\n

eg   \n\ncos\n\n\n\n(\n\n2\n\n(\n\n2\nx\n\n)\n\n\n)\n\n,  \n2\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\n\n(\n\n2\nθ\n\n)\n\n\n1\n\n1\n\n2\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\n\n(\n\n2\nθ\n\n)\n\n,  \n\nco\n\n\n\n\ns\n\n2\n\n\n\n\n(\n\n2\nθ\n\n)\n\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\n\n(\n\n2\nθ\n\n)\n\n

\n

correct substitution of their value of \n\ncos\n\n\n\n(\n\n2\nx\n\n)\n\n and/or \n\nsin\n\n\n\n(\n\n2\nx\n\n)\n\n into formula for \n\ncos\n\n\n\n(\n\n4\nx\n\n)\n\n     (A1)

\n

eg   \n2\n\n\n\n(\n\n\n7\n9\n\n\n)\n\n2\n\n\n\n1\n,  \n\n\n98\n\n\n81\n\n\n\n1\n,  \n1\n\n2\n\n\n\n(\n\n\n\n2\n\n8\n\n\n9\n\n\n)\n\n2\n\n\n,  \n1\n\n\n\n64\n\n\n81\n\n\n,  \n\n\n\n(\n\n\n7\n9\n\n\n)\n\n2\n\n\n\n\n\n\n(\n\n\n\n2\n\n8\n\n\n9\n\n\n)\n\n2\n\n\n,  \n\n\n49\n\n\n81\n\n\n\n\n\n32\n\n\n81\n\n\n

\n

\n\ncos\n\n\n\n(\n\n4\nx\n\n)\n\n=\n\n\n17\n\n\n81\n\n\n      A1 N2

\n

 

\n

 

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METHOD 2

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recognizing 4\nx\n is double angle of 2\nx\n (seen anywhere)      (M1)

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eg   \n\ncos\n\n\n\n(\n\n2\n\n(\n\n2\nx\n\n)\n\n\n)\n\n

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double angle identity for 2\nx\n     (M1)

\n

eg   \n2\n\n\nco\n\n\n\n\ns\n\n2\n\n\n\n\n(\n\n2\nθ\n\n)\n\n\n1\n\n1\n\n2\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\n(\n\n2\nx\n\n)\n\n,  \n\nco\n\n\n\n\ns\n\n2\n\n\n\n\n(\n\n2\nθ\n\n)\n\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\n\n(\n\n2\nθ\n\n)\n\n

\n

correct expression for \n\ncos\n\n\n\n(\n\n4\nx\n\n)\n\n in terms of \n\nsin\n\n\nx\n and/or \n\ncos\n\n\nx\n     (A1)

\n

eg   \n2\n\n\n\n(\n\n1\n\n2\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n)\n\n2\n\n\n\n1\n,  \n1\n\n2\n\n\n\n(\n\n2\n\n\nsin\n\n\nx\n\n\ncos\n\n\nx\n\n)\n\n2\n\n\n,  \n\n\n\n(\n\n1\n\n2\n\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nθ\n\n)\n\n2\n\n\n\n\n\n\n(\n\n2\n\n\nsin\n\n\nθ\n\n\ncos\n\n\nθ\n\n)\n\n2\n\n\n

\n

correct substitution for \n\nsin\n\n\nx\n and/or \n\ncos\n\n\nx\n     A1

\n

eg   \n2\n\n\n\n(\n\n1\n\n2\n\n\n\n\n(\n\n\n1\n3\n\n\n)\n\n\n2\n\n\n\n)\n\n2\n\n\n\n1\n,  \n2\n\n(\n\n1\n\n4\n\n\n\n\n(\n\n\n1\n3\n\n\n)\n\n\n2\n\n\n+\n4\n\n\n\n\n(\n\n\n1\n3\n\n\n)\n\n\n4\n\n\n\n)\n\n\n1\n,  \n1\n\n2\n\n\n\n(\n\n2\n×\n\n1\n3\n\n×\n\n\n\n8\n\n\n3\n\n\n)\n\n2\n\n\n

\n

correct working      (A1)

\n

eg   \n2\n\n(\n\n\n\n49\n\n\n81\n\n\n\n)\n\n\n1\n,  \n1\n\n2\n\n(\n\n\n\n32\n\n\n81\n\n\n\n)\n\n,  \n\n\n49\n\n\n81\n\n\n\n\n\n32\n\n\n81\n\n\n

\n

\n\ncos\n\n\n\n(\n\n4\nx\n\n)\n\n=\n\n\n17\n\n\n81\n\n\n      A1 N2

\n

 

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[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.1.SL.TZ0.S_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-6-pythagorean-identity-double-angles" ] }, { "Question": "
\n

A biased four-sided die, A, is rolled. Let X be the score obtained when die A is rolled. The probability distribution for X is given in the following table.

\n

\n
\n

A second biased four-sided die, B, is rolled. Let Y be the score obtained when die B is rolled.
The probability distribution for Y is given in the following table.

\n

\n
\n

Find the value of p.

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[2]
\n
a.
\n
\n

Hence, find the value of E(X) .

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[2]
\n
b.
\n
\n

State the range of possible values of r.

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[1]
\n
c.i.
\n
\n

Hence, find the range of possible values of q.

\n
[2]
\n
c.ii.
\n
\n

Hence, find the range of possible values for E(Y).

\n
[3]
\n
d.
\n
\n

Agnes and Barbara play a game using these dice. Agnes rolls die A once and Barbara rolls die B once. The probability that Agnes’ score is less than Barbara’s score is 12.

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Find the value of E(Y).

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[6]
\n
e.
\n
", "Markscheme": "
\n

recognising probabilities sum to 1          (M1)

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p+p+p+12p=1

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p=27           A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

valid attempt to find E(X)          (M1)

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1×p+2×p+3×p+4×12p=8p

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E(X)=167           A1

\n

 

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[2 marks]

\n
b.
\n
\n

0r1       A1

\n

 

\n

[1 mark]

\n
c.i.
\n
\n

attempt to find a value of q         (M1)

\n

01-3q1  OR  r=0q=13  OR  r=1q=0

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0q13       A1

\n

 

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[2 marks]

\n
c.ii.
\n
\n

E(Y)=1×q+2×q+3×q+4×r (=2+2r  OR  4-6q)         (A1)

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one correct boundary value       A1

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1×13+2×13+3×13+4×0=2 OR

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1×0+2×0+3×0+4×1=4 OR

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2+20=2 OR

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2+21=4 OR

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4-60=4 OR 4-613=2

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2E(Y)4       A1

\n

 

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[3 marks]

\n
d.
\n
\n

METHOD 1

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evidence of choosing at least four correct outcomes from

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1&2, 1&3, 1&4, 2&3, 2&4, 3&4         (M1)

\n

67q+67r  OR  3pq+3pr  OR  pq+pq+p1-3q+pq+p1-3q+p1-3q         (A1)

\n

solving for either q or r        M1

\n

67q+1-3q=12  OR  671-r3+r=12  OR  3pq+3p1-3q=12

\n

        OR  3p1-r3+3pr=12

\n

 

\n

EITHER two correct values

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q=524  and  r=38      A1A1

\n

 

\n

OR one correct value

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q=524  OR  r=38      A1

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substituting their value for q or r      A1

\n

4-6524  OR  2+238

\n

 

\n

THEN

\n

E(Y)=114      A1

\n

 

\n

METHOD 2 (solving for E(Y))

\n

evidence of choosing at least four correct outcomes from

\n

1&2, 1&3, 1&4, 2&3, 2&4, 3&4         (M1)

\n

67q+67r  OR  3pq+3pr  OR  pq+pq+p1-3q+pq+p1-3q+p1-3q         (A1)

\n

rearranging to make q the subject      M1

\n

q=4-EY6

\n

3pq+3p1-3q=12      M1

\n

67×4-E(Y)6+671-34-E(Y)6=12       A1

\n

2E(Y)-17=12

\n

E(Y)=114       A1

\n

 

\n

[6 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.1.SL.TZ1.9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

The following diagram shows quadrilateral ABCD.

\n

\n

\n\nAB\n\n=\n11\n\n\ncm,\n\n\n\n\nBC\n\n=\n6\n\n\ncm,\n\n\n\n\nB\n\n\n\nA\n\n\n\n\n\n\nD  =  100\n\n\n\n\n, and C\n\n\n\nB\n\n\n\n\n\n\nD  =  82\n\n\n\n

\n
\n

Find DB.

\n
[3]
\n
a.
\n
\n

Find DC.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of choosing sine rule      (M1)

\n

eg      a sin  A = b sin  B = c sin  C

\n

correct substitution      (A1)
eg      DB sin  59 = 11 sin  100

\n

9.57429

\n

DB = 9.57 (cm)      A1 N2

\n

[3 marks]

\n
a.
\n
\n

evidence of choosing cosine rule     (M1)

\n

eg    a 2 = b 2 + c 2 2 b c cos ( A ) , D C 2 = D B 2  +  B C 2    2DB × BC × cos ( D B C )  

\n

correct substitution into RHS      (A1)
eg    9.57 2 + 6 2 2 × 9.57 × 6 × cos 82 , 111.677   

\n

10.5677

\n

DC = 10.6 (cm)      A1 N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.SL.TZ2.S_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Two points P and Q have coordinates (3, 2, 5) and (7, 4, 9) respectively.

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\n

Let \n\n\n\n\nPR\n\n\n\n\n\n = 6i − j + 3k.

\n
\n

Find  PQ .

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[2]
\n
a.i.
\n
\n

Find | PQ | .

\n
[2]
\n
a.ii.
\n
\n

Find the angle between PQ and PR.

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[4]
\n
b.
\n
\n

Find the area of triangle PQR.

\n
[2]
\n
c.
\n
\n

Hence or otherwise find the shortest distance from R to the line through P and Q.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

valid approach      (M1)

\n

eg   (7, 4, 9) − (3, 2, 5)  A − B

\n

PQ = 4i + 2j + 4k  ( = ( 4 2 4 ) )      A1 N2

\n

[2 marks]

\n
a.i.
\n
\n

correct substitution into magnitude formula      (A1)
eg   4 2 + 2 2 + 4 2

\n

| PQ | = 6      A1 N2

\n

[2 marks]

\n
a.ii.
\n
\n

finding scalar product and magnitudes      (A1)(A1)

\n

scalar product = (4 × 6) + (2 × (−1) + (4 × 3) (= 34)

\n

magnitude of PR =  36 + 1 + 9 = ( 6.782 )

\n

correct substitution of their values to find cos  Q P R      M1

\n

eg  cos  Q P R  =  24 2 + 12 ( 6 ) × ( 46 ) , 0.8355

\n

0.581746

\n

Q P R = 0.582 radians  or  Q P R = 33.3°     A1 N3

\n

[4 marks]

\n
b.
\n
\n

correct substitution (A1)
eg     1 2 × | PQ | × | PR | × sin P , 1 2 × 6 × 46 × sin 0.582

\n

area is 11.2 (sq. units)      A1 N2

\n

[2 marks]

\n
c.
\n
\n

recognizing shortest distance is perpendicular distance from R to line through P and Q      (M1)

\n

eg  sketch, height of triangle with base  [ PQ ] , 1 2 × 6 × h , sin 33.3 = h 46

\n

correct working      (A1)

\n

eg   1 2 × 6 × d = 11.2 , | PR | × sin P , 46 × sin 33.3

\n

3.72677

\n

distance = 3.73  (units)    A1 N2

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18M.2.SL.TZ2.S_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

At Grande Anse Beach the height of the water in metres is modelled by the function \nh\n(\nt\n)\n=\np\ncos\n\n(\nq\n×\nt\n)\n+\nr\n, where \nt\n is the number of hours after 21:00 hours on 10 December 2017. The following diagram shows the graph of \nh\n , for \n0\n\nt\n\n72\n.

\n

\"M17/5/MATME/SP2/ENG/TZ1/08\"

\n

The point \n\nA\n\n(\n6.25\n,\n\n \n\n0.6\n)\n represents the first low tide and \n\nB\n\n(\n12.5\n,\n\n \n\n1.5\n)\n represents the next high tide.

\n
\n

How much time is there between the first low tide and the next high tide?

\n
[2]
\n
a.i.
\n
\n

Find the difference in height between low tide and high tide.

\n
[2]
\n
a.ii.
\n
\n

Find the value of p ;

\n
[2]
\n
b.i.
\n
\n

Find the value of q ;

\n
[3]
\n
b.ii.
\n
\n

Find the value of r .

\n
[2]
\n
b.iii.
\n
\n

There are two high tides on 12 December 2017. At what time does the second high tide occur?

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

attempt to find the difference of x -values of A and B     (M1)

\n

eg 6.25 12.5  

\n

6.25 (hours), (6 hours 15 minutes)     A1     N2

\n

[2 marks]

\n
a.i.
\n
\n

attempt to find the difference of y -values of A and B     (M1)

\n

eg 1.5 0.6

\n

0.9  (m)     A1     N2

\n

[2 marks]

\n
a.ii.
\n
\n

valid approach     (M1)

\n

eg max min 2 ,   0.9 ÷ 2

\n

p = 0.45     A1     N2

\n

[2 marks]

\n
b.i.
\n
\n

METHOD 1

\n

period = 12.5 (seen anywhere)     (A1)

\n

valid approach (seen anywhere)     (M1)

\n

eg period = 2 π b ,   q = 2 π period ,   2 π 12.5

\n

0.502654

\n

q = 4 π 25 ,  0.503  ( or  4 π 25 ,   0.503 )     A1     N2

\n

METHOD 2

\n

attempt to use a coordinate to make an equation     (M1)

\n

eg p cos ( 6.25 q ) + r = 0.6 ,   p cos ( 12.5 q ) + r = 1.5

\n

correct substitution     (A1)

\n

eg 0.45 cos ( 6.25 q ) + 1.05 = 0.6 ,   0.45 cos ( 12.5 q ) + 1.05 = 1.5

\n

0.502654

\n

q = 4 π 25 ,   0.503   ( or  4 π 25 ,   0.503 )     A1     N2

\n

[3 marks]

\n
b.ii.
\n
\n

valid method to find r     (M1)

\n

eg max + min 2 ,   0.6 + 0.45

\n

r = 1.05     A1     N2

\n

[2 marks]

\n
b.iii.
\n
\n

METHOD 1

\n

attempt to find start or end t -values for 12 December     (M1)

\n

eg 3 + 24 ,   t = 27 ,   t = 51

\n

finds t -value for second max     (A1)

\n

t = 50

\n

23:00 (or 11 pm)     A1     N3

\n

METHOD 2 

\n

valid approach to list either the times of high tides after 21:00 or the t -values of high tides after 21:00, showing at least two times     (M1) 

\n

eg 21:00 + 12.5 ,  21:00 + 25 ,   12.5 + 12.5 ,   25 + 12.5

\n

correct time of first high tide on 12 December     (A1)

\n

eg 10:30 (or 10:30 am) 

\n

time of second high tide = 23:00     A1     N3

\n

METHOD 3

\n

attempt to set their h equal to 1.5     (M1)

\n

eg h ( t ) = 1.5 ,   0.45 cos ( 4 π 25 t ) + 1.05 = 1.5

\n

correct working to find second max     (A1)

\n

eg 0.503 t = 8 π ,   t = 50

\n

23:00 (or 11 pm)     A1     N3

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.SL.TZ1.S_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

A communication tower, T, produces a signal that can reach cellular phones within a radius of 32 km. A straight road passes through the area covered by the tower’s signal.

\n

The following diagram shows a line representing the road and a circle representing the area covered by the tower’s signal. Point R is on the circumference of the circle and points S and R are on the road. Point S is 38 km from the tower and RŜT = 43˚.

\n

\n
\n

Let SR = \nx\n. Use the cosine rule to show that \n\n\nx\n2\n\n\n\n\n(\n\n76\n\n\ncos\n\n\n\n43\n\n\n\n)\n\nx\n+\n420\n=\n0\n.

\n
[2]
\n
a.
\n
\n

Hence or otherwise, find the total distance along the road where the signal from the tower can reach cellular phones.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognizing TR =32  (seen anywhere, including diagram)      A1

\n

correct working      A1

\n

eg   \n\n\n32\n2\n\n\n=\n\n\nx\n2\n\n\n+\n\n\n38\n2\n\n\n\n2\n\n(\nx\n)\n\n\n(\n\n38\n\n)\n\n\ncos\n\n\n\n43\n\n\n\n1024\n=\n1444\n+\n\n\nx\n2\n\n\n\n76\n\n\n(\nx\n)\n\n\ncos\n\n\n\n43\n\n\n

\n

\n\n\nx\n2\n\n\n\n\n(\n\n76\n\n\ncos\n\n\n\n43\n\n\n\n)\n\nx\n+\n420\n=\n0\n     AG N0

\n

 

\n

[2 marks]

\n
a.
\n
\n

Note: There are many approaches to this question, depending on which triangle the candidate has used, and whether they used the cosine rule and/or the sine rule. Please check working carefully and award marks in line with the markscheme.

\n

 

\n

METHOD 1

\n

correct values for \nx\n (seen anywhere)      A1A1

\n

\nx\n = 9.02007,  46.5628

\n

recognizing the need to find difference in values of \nx\n      (M1)

\n

eg     46.5 − 9.02,   \n\n\nx\n1\n\n\n\n\n\nx\n2\n\n\n

\n

37.5427

\n

37.5 (km)     A1 N2

\n

 

\n

METHOD 2

\n

correct use of sine rule in ΔSRT

\n

eg     \n\n\n\nsin\n\n\n\nS\n\n\n\nR\n\n\n\n\n\nT\n\n\n\n38\n\n\n=\n\n\n\nsin\n\n\n\n43\n\n\n\n\n32\n\n\n\n\n\nS\n\n\n\nR\n\n\n\n\n\nT\n\n\n = 54.0835°     (A1)

\n

recognizing isosceles triangle (seen anywhere)      (M1)

\n

eg     \n\n\nT\n^\n\n\n=\n\n180\n\n\n\n2\n\n\n54.0835\n\n\n, two sides of 32

\n

correct working to find distance      A1

\n

eg     \n\n\n\n\n32\n\n2\n\n\n+\n\n\n\n32\n\n2\n\n\n\n2\n\n32\n\n32\n\n\ncos\n\n\n\n(\n\n\n180\n\n\n\n\n2\n\n\n54.0835\n\n\n\n)\n\n\n,

\n

\n\n\n\nsin\n\n\n\n71.8329\n\n\n\nd\n\n=\n\n\n\nsin\n\n\n\n54.0835\n\n\n\n\n32\n\n\n,  \n\n\n32\n2\n\n\n=\n\n\n32\n2\n\n\n+\n\n\nx\n2\n\n\n\n2\n\n32\nx\n\n\ncos\n\n\n(\n\n\n0\n\n\n.944\n\n\n)\n\n

\n

37.5427

\n

37.5 (km)     A1 N2

\n

 

\n

[4 marks]

\n

 

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.2.SL.TZ0.S_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Triangle ABC has a = 8.1 cm, b = 12.3 cm and area 15 cm2. Find the largest possible perimeter of triangle ABC.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct substitution into the formula for area of a triangle      (A1)

\n

eg  15 =  1 2 × 8.1 × 12.3 × sin C

\n

correct working for angle C    (A1)

\n

eg  sin C = 0.301114, 17.5245…, 0.305860

\n

recognizing that obtuse angle needed      (M1)

\n

eg  162.475, 2.83573, cos C < 0

\n

evidence of choosing the cosine rule      (M1)

\n

eg  a2 = b2 + c2 − 2bc cos(A)

\n

correct substitution into cosine rule to find c     (A1)

\n

eg  c2 = (8.1)2 + (12.3)2 − 2(8.1)(12.3) cos C

\n

c = 20.1720    (A1)

\n

8.1 + 12.3 + 20.1720 = 40.5720

\n

perimeter = 40.6    A1 N4

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.SL.TZ1.S_6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule" ] }, { "Question": "
\n

Consider the points A(−3, 4, 2) and B(8, −1, 5).

\n
\n

A line L has vector equation \nr\n=\n\n(\n\n\n\n\n2\n\n\n\n\n0\n\n\n\n\n\n\n5\n\n\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n1\n\n\n\n\n\n\n2\n\n\n\n\n\n2\n\n\n\n\n)\n\n. The point C (5, \ny\n, 1) lies on line L.

\n
\n

Find  AB .

\n
[2]
\n
a.i.
\n
\n

Find | AB | .

\n
[2]
\n
a.ii.
\n
\n

Find the value of y .

\n
[3]
\n
b.i.
\n
\n

Show that AC = ( 8 10 1 ) .

\n
[2]
\n
b.ii.
\n
\n

Find the angle between AB and AC .

\n
[5]
\n
c.
\n
\n

Find the area of triangle ABC.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

Note: There may be slight differences in answers, depending on which combination of unrounded values and previous correct 3 sf values the candidates carry through in subsequent parts. Accept answers that are consistent with their working.

\n

 

\n

valid approach      (M1)

\n

eg     B − A,  AO + OB,   ( 8 1 5 ) ( 3 4 2 )

\n

AB = ( 11 5 3 )      A1 N2

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

Note: There may be slight differences in answers, depending on which combination of unrounded values and previous correct 3 sf values the candidates carry through in subsequent parts. Accept answers that are consistent with their working.

\n

 

\n

correct substitution into formula      (A1)

\n

eg    11 2 + ( 5 ) 2 + 3 2

\n

12.4498 

\n

| AB | = 155   (exact), 12.4     A1 N2

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

Note: There may be slight differences in answers, depending on which combination of unrounded values and previous correct 3 sf values the candidates carry through in subsequent parts. Accept answers that are consistent with their working.

\n

 

\n

valid approach to find t       (M1)

\n

eg      ( 5 y 1 ) = ( 2 0 5 ) + t ( 1 2 2 ) ,   5 = 2 + t ,    1 = 5 + 2 t

\n

t = 3      (seen anywhere)      (A1)

\n

attempt to substitute their parameter into the vector equation      (M1)

\n

eg      ( 5 y 1 ) = ( 2 0 5 ) + 3 ( 1 2 2 ) ,   3 ( 2 )

\n

y = 6      A1 N2

\n

 

\n

[3 marks]

\n
b.i.
\n
\n

Note: There may be slight differences in answers, depending on which combination of unrounded values and previous correct 3 sf values the candidates carry through in subsequent parts. Accept answers that are consistent with their working.

\n

 

\n

correct approach      A1

\n

eg      ( 5 6 1 ) ( 3 4 2 ) ,  AO + OC,   c a

\n

AC = ( 8 10 1 )      AG N0

\n

Note: Do not award A1 in part (ii) unless answer in part (i) is correct and does not result from working backwards.

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

Note: There may be slight differences in answers, depending on which combination of unrounded values and previous correct 3 sf values the candidates carry through in subsequent parts. Accept answers that are consistent with their working.

\n

 

\n

finding scalar product and magnitude      (A1)(A1)

\n

scalar product = 11 × 8 + −5 × −10 + 3 × −1  (=135)

\n

| AC | = 8 2 + ( 10 ) 2 + ( 1 ) 2 ( = 165 , 12.8452 )

\n

evidence of substitution into formula      (M1)

\n

eg  cos θ = 11 × 8 + 5 × 10 + 3 × 1 | AB | × 8 2 + ( 10 ) 2 + ( 1 ) 2 , cos θ = AB AC 155 × 8 2 + ( 10 ) 2 + ( 1 ) 2

\n

correct substitution      (A1)

\n

eg     cos θ = 11 × 8 + 5 × 10 + 3 × 1 155 × 8 2 + ( 10 ) 2 + ( 1 ) 2 ,    cos θ = 135 159.921 ,

\n

cos θ = 0.844162

\n

0.565795,  32.4177°

\n

A ^ = 0.566,  32.4°     A1 N3

\n

 

\n

[5 marks]

\n
c.
\n
\n

Note: There may be slight differences in answers, depending on which combination of unrounded values and previous correct 3 sf values the candidates carry through in subsequent parts. Accept answers that are consistent with their working.

\n

 

\n

correct substitution into area formula      (A1)

\n

eg    1 2 × 155 × 165 × sin ( 0.566 ) ,   1 2 × 155 × 165 × sin ( 32.4 )

\n

42.8660

\n

area = 42.9      A1 N2

\n

 

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18N.2.SL.TZ0.S_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

It is given that cosecθ=32, where π2<θ<3π2. Find the exact value of cotθ.

\n
", "Markscheme": "
\n

METHOD 1

\n

attempt to use a right angled triangle        M1

\n

\n

correct placement of all three values and θ seen in the triangle        (A1)

\n

cotθ<0 (since cosecθ>0 puts θ in the second quadrant)        R1

\n

cotθ=-52        A1

\n

Note: Award M1A1R0A0 for cotθ=52 seen as the final answer
         The R1 should be awarded independently for a negative value only given as a final answer.

\n

 

\n

METHOD 2

\n

Attempt to use 1+cot2θ=cosec2θ        M1

\n

1+cot2θ=94

\n

cot2θ=54        (A1)

\n

cotθ=±52

\n

cotθ<0 (since cosecθ>0 puts θ in the second quadrant)        R1

\n

cotθ=-52        A1

\n

Note: Award M1A1R0A0 for cotθ=52 seen as the final answer
         The R1 should be awarded independently for a negative value only given as a final answer.

\n

 

\n

METHOD 3

\n

sinθ=23

\n

attempt to use sin2θ+cos2θ=1        M1

\n

49+cos2θ=1

\n

cos2θ=59        (A1)

\n

cosθ=±53

\n

cosθ<0 (since cosecθ>0 puts θ in the second quadrant)        R1

\n

cosθ=-53

\n

cotθ=-52        A1

\n

 

\n

Note: Award M1A1R0A0 for cotθ=52 seen as the final answer
         The R1 should be awarded independently for a negative value only given as a final answer.

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.AHL.TZ1.6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-9-reciprocal-trig-ratios-and-their-pythagorean-identities-inverse-circular-functions" ] }, { "Question": "
\n

Consider the quartic equation z4+4z3+8z2+80z+400=0, z.

\n

Two of the roots of this equation are a+bi and b+ai, where a, b.

\n

Find the possible values of a.

\n
", "Markscheme": "
\n

METHOD 1

\n

other two roots are a-bi and b-ai        A1

\n

sum of roots =-4 and product of roots =400       A1

\n

attempt to set sum of four roots equal to -4 or 4 OR
attempt to set product of four roots equal to 400        M1

\n

a+bi+a-bi+b+ai+bai=4

\n

2a+2b=4(a+b=2)         A1

\n

(a+bi)(abi) (b+ai)(bai)=400

\n

a2+b22=400         A1

\n

a2+b2=20

\n

attempt to solve simultaneous equations             (M1)

\n

a=2 or a=-4           A1A1

\n

 

\n

METHOD 2

\n

other two roots are a-bi and b-ai        A1

\n

z-a+biz-a-biz-b+aiz-b-ai=0        A1

\n

z-a2+b2z-b2+a2=0

\n

z2-2az+a2+b2z2-2bz+b2+a2=0        A1

\n

Attempt to equate coefficient of z3 and constant with the given quartic equation        M1

\n

-2a-2b=4 and a2+b22=400        A1

\n

attempt to solve simultaneous equations             (M1)

\n

a=2 or a=-4           A1A1

\n

 

\n

[8 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.AHL.TZ1.7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n12\n\n\n\ncos\n\n\nx\n\n5\n\n\n\nsin\n\n\nx\n,\n\n\n\nπ\n\nx\n\n2\nπ\n, be a periodic function with \nf\n\n(\nx\n)\n\n=\nf\n\n(\n\nx\n+\n2\nπ\n\n)\n\n

\n

The following diagram shows the graph of \nf\n.

\n

\n

There is a maximum point at A. The minimum value of \nf\n is −13 .

\n
\n

A ball on a spring is attached to a fixed point O. The ball is then pulled down and released, so that it moves back and forth vertically.

\n

\n

The distance, d centimetres, of the centre of the ball from O at time t seconds, is given by

\n

\nd\n\n(\nt\n)\n\n=\nf\n\n(\nt\n)\n\n+\n17\n,\n\n\n0\n\nt\n\n5.\n

\n
\n

Find the coordinates of A.

\n
[2]
\n
a.
\n
\n

For the graph of \nf\n, write down the amplitude.

\n
[1]
\n
b.i.
\n
\n

For the graph of \nf\n, write down the period.

\n
[1]
\n
b.ii.
\n
\n

Hence, write \nf\n\n(\nx\n)\n\n in the form \np\n\n\n\ncos\n\n\n\n(\n\nx\n+\nr\n\n)\n\n.

\n
[3]
\n
c.
\n
\n

Find the maximum speed of the ball.

\n
[3]
\n
d.
\n
\n

Find the first time when the ball’s speed is changing at a rate of 2 cm s−2.

\n
[5]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

−0.394791,13

\n

A(−0.395, 13)      A1A1 N2

\n

[2 marks]

\n
a.
\n
\n

13      A1 N1

\n

[1 mark]

\n
b.i.
\n
\n

\n\n2\nπ\n\n, 6.28      A1 N1

\n

[1 mark]

\n
b.ii.
\n
\n

valid approach      (M1)

\n

eg recognizing that amplitude is p or shift is r

\n

\nf\n\n(\nx\n)\n\n=\n13\n\n\n\ncos\n\n\n\n(\n\nx\n+\n0.395\n\n)\n\n   (accept p = 13, r = 0.395)     A1A1 N3

\n

Note: Accept any value of r of the form \n0.395\n+\n2\nπ\nk\n,\n\n\nk\n\n\nZ\n\n

\n

[3 marks]

\n
c.
\n
\n

recognizing need for d ′(t)      (M1)

\n

eg  −12 sin(t) − 5 cos(t)

\n

correct approach (accept any variable for t)      (A1)

\n

eg  −13 sin(t + 0.395), sketch of d′, (1.18, −13), t = 4.32

\n

maximum speed = 13 (cms−1)      A1 N2

\n

[3 marks]

\n
d.
\n
\n

recognizing that acceleration is needed      (M1)

\n

eg   a(t), d \"(t)

\n

correct equation (accept any variable for t)      (A1)

\n

eg  \na\n\n(\nt\n)\n\n=\n\n2\n,\n\n\n\n|\n\n\n\nd\n\n\n\nd\n\nt\n\n\n\n(\n\n\nd\n\n\n\n(\nt\n)\n\n\n)\n\n\n|\n\n=\n2\n,\n\n\n\n12\n\n\n\ncos\n\n\n\n(\nt\n)\n\n+\n5\n\n\n\nsin\n\n\n\n(\nt\n)\n\n=\n\n2\n

\n

valid attempt to solve their equation   (M1)

\n

eg  sketch, 1.33

\n

1.02154

\n

1.02      A2 N3

\n

[5 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.2.SL.TZ1.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

Use l’Hôpital’s rule to find limx0arctan2xtan3x.

\n
", "Markscheme": "
\n

attempt to differentiate numerator and denominator        M1

\n

limx0arctan2xtan3x

\n

=limx021+4x23sec23x        A1A1

\n

 

\n

Note: A1 for numerator and A1 for denominator. Do not condone absence of limits.

\n

 

\n

attempt to substitute x=0         (M1)

\n

=23        A1

\n

 

\n

Note: Award a maximum of M1A1A0M1A1 for absence of limits.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.1.AHL.TZ1.8", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

A farmer has six sheep pens, arranged in a grid with three rows and two columns as shown in the following diagram.

\n

\n

Five sheep called Amber, Brownie, Curly, Daisy and Eden are to be placed in the pens. Each pen is large enough to hold all of the sheep. Amber and Brownie are known to fight.

\n

Find the number of ways of placing the sheep in the pens in each of the following cases:

\n
\n

Each pen is large enough to contain five sheep. Amber and Brownie must not be placed in the same pen.

\n
[4]
\n
a.
\n
\n

Each pen may only contain one sheep. Amber and Brownie must not be placed in pens which share a boundary.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

B has one less pen to select         (M1)

\n


EITHER

\n

A and B can be placed in 6×5 ways        (A1)

\n

C, D, E have 6 choices each        (A1)

\n


OR

\n

A (or B), C, D, E have 6 choices each        (A1)

\n

B (or A) has only 5 choices        (A1)

\n


THEN

\n

5×64 =6480            A1

\n

 

\n

METHOD 2

\n

total number of ways =65        (A1)

\n

number of ways with Amber and Brownie together =64        (A1)

\n

attempt to subtract (may be seen in words)        (M1)

\n

65-64

\n

=5×64 =6480          A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

METHOD 1

\n

total number of ways =6!(=720)        (A1)

\n

number of ways with Amber and Brownie sharing a boundary

\n

      =2×7×4!(=336)        (A1)

\n

attempt to subtract (may be seen in words)        (M1)

\n

720-336=384          A1

\n

 

\n

METHOD 2

\n

case 1: number of ways of placing A in corner pen

\n

3×4×3×2×1

\n

Four corners total no of ways is 4×(3×4×3×2×1)=12×4!(=288)        (A1)

\n

case 2: number of ways of placing A in the middle pen

\n

2×4×3×2×1

\n

two middle pens so 2×(2×4×3×2×1)=4×4!(=96)        (A1)

\n

attempt to add (may be seen in words)        (M1)

\n

total no of ways =288+96

\n

=16×4!(=384)          A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.1.AHL.TZ1.9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

Consider the line L1 defined by the Cartesian equation x+12=y=3-z.

\n
\n

Consider a second line L2 defined by the vector equation r=012+ta1-1, where t and a.

\n
\n

Show that the point (-1, 0, 3) lies on L1.

\n
[1]
\n
a.i.
\n
\n

Find a vector equation of L1.

\n
[3]
\n
a.ii.
\n
\n

Find the possible values of a when the acute angle between L1 and L2 is 45°.

\n
[8]
\n
b.
\n
\n

It is given that the lines L1 and L2 have a unique point of intersection, A, when ak.

\n

Find the value of k, and find the coordinates of the point A in terms of a.

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

-1+12=0=3-3          A1

\n

the point (-1, 0, 3) lies on L1.          AG

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

attempt to set equal to a parameter or rearrange cartesian form          (M1)

\n

x+12=y=3-z=λx=2λ-1, y=λ, z=3-λ  OR  x+12=y-01=z-3-1

\n

correct direction vector 21-1 or equivalent seen in vector form          (A1)

\n

r=-103+λ21-1 (or equivalent)          A1

\n

 

\n

Note: Award A0 if =r is omitted.

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

attempt to use the scalar product formula          (M1)

\n

21-1a1-1=±6a2+2cos45°          (A1)(A1)

\n

 

\n

Note: Award A1 for LHS and A1 for RHS

\n

 

\n

2a+2=±6a2+2222a+2=±3a2+2         A1A1

\n

 

\n

Note: Award A1 for LHS and A1 for RHS

\n

 

\n

4a2+8a+4=3a2+6         A1

\n

a2+8a-2=0        M1

\n

attempt to solve their quadratic

\n

a=-8±64+82=-8±722=-4±32         A1

\n

 

\n

[8 marks]

\n
b.
\n
\n

METHOD 1

\n

attempt to equate the parametric forms of L1 and L2         (M1)

\n

2λ-1=taλ=1+t3-λ=2-t         A1

\n

attempt to solve equations by eliminating λ or t         (M1)

\n

2+2t-1=ta1=ta-2  or  2λ-1=λ-1aa-1=λa-2

\n

Solutions exist unless a-2=0

\n

k=2         A1

\n

 

\n

Note: This A1 is independent of the following marks.

\n

 

\n

t=1a-2  or  λ=a-1a-2         A1

\n

A has coordinates aa-2, 1+1a-2, 2-1a-2 =aa-2, a-1a-2, 2a-5a-2         A2

\n

 

\n

Note: Award A1 for any two correct coordinates seen or final answer in vector form.

\n

 

\n

 

\n

METHOD 2

\n

no unique point of intersection implies direction vectors of L1 and L2 parallel

\n

k=2         A1

\n

 

\n

Note: This A1 is independent of the following marks.

\n

 

\n

attempt to equate the parametric forms of L1 and L2         (M1)

\n

2λ-1=taλ=1+t3-λ=2-t         A1

\n

attempt to solve equations by eliminating λ or t         (M1)

\n

2+2t-1=ta1=ta-2  or  2λ-1=λ-1aa-1=λa-2

\n

t=1a-2  or  λ=a-1a-2         A1

\n

A has coordinates aa-2, 1+1a-2, 2-1a-2 =aa-2, a-1a-2, 2a-5a-2         A2

\n

 

\n

Note: Award A1 for any two correct coordinates seen or final answer in vector form.

\n

 

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.1.AHL.TZ1.11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

The depth of water in a port is modelled by the function \nd\n(\nt\n)\n=\np\ncos\n\nq\nt\n+\n7.5\n, for \n0\n\nt\n\n12\n, where \nt\n is the number of hours after high tide.

\n

At high tide, the depth is 9.7 metres.

\n

At low tide, which is 7 hours later, the depth is 5.3 metres.

\n
\n

Find the value of \np\n.

\n
[2]
\n
a.
\n
\n

Find the value of \nq\n.

\n
[2]
\n
b.
\n
\n

Use the model to find the depth of the water 10 hours after high tide.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\n\n\nmax\n\n\n\nmin\n\n\n2\n\n, sketch of graph, \n9.7\n=\np\ncos\n\n(\n0\n)\n+\n7.5\n

\n

\np\n=\n2.2\n     A1     N2

\n

[2 marks]

\n
a.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\nB\n=\n\n\n2\nπ\n\n\n\nperiod\n\n\n\n, period is \n14\n,\n\n \n\n\n\n360\n\n\n14\n\n\n,\n\n \n\n5.3\n=\n2.2\ncos\n\n7\nq\n+\n7.5\n

\n

0.448798

\n

\nq\n=\n\n\n2\nπ\n\n\n14\n\n\n\n \n\n\n(\n\n\nπ\n7\n\n\n)\n\n, (do not accept degrees)     A1     N2

\n

[2 marks]

\n
b.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\nd\n(\n10\n)\n,\n\n \n\n2.2\ncos\n\n\n(\n\n\n\n20\nπ\n\n\n14\n\n\n\n)\n\n+\n7.5\n

\n

7.01045

\n

7.01 (m)     A1     N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.2.SL.TZ2.S_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

Find 6x+7dx.

\n
[3]
\n
a.
\n
\n

Given f'x=6x+7 and f1.2=7.32, find fx.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

correct integration 3x2+7x+c        A1A1A1

\n

 

\n

Note: Award A1 for 3x2, A1 for 7x and A1 for +c

\n

 

\n

[3 marks]

\n
a.
\n
\n

recognition that fx=f'xdx        (M1)

\n

31.22+71.2+c=7.32        (A1)

\n

c=-5.4

\n

fx=3x2+7x-5.4        A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.SL.TZ1.1", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

The following table shows the data collected from an experiment.

\n

\n

The data is also represented on the following scatter diagram.

\n

\n

The relationship between x and y can be modelled by the regression line of y on x with equation y=ax+b, where a, b.

\n
\n

Write down the value of a and the value of b.

\n
[2]
\n
a.
\n
\n

Use this model to predict the value of y when x=18.

\n
[2]
\n
b.
\n
\n

Write down the value of x¯ and the value of y¯.

\n
[1]
\n
c.
\n
\n

Draw the line of best fit on the scatter diagram.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

a=0.433156, b=4.50265

\n

a=0.433, b=4.50        A1A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

attempt to substitute x=18 into their equation        (M1)

\n

y=0.433×18+4.50

\n

=12.2994

\n

=12.3        A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

x¯=15,  y¯=11        A1

\n

 

\n

[1 mark]

\n
c.
\n
\n

        A1A1

\n

Note: Award marks as follows:

\n

A1 for a straight line going through 15,11

\n

A1 for intercepting the y-axis between their b±1.5 (when their line is extended), which includes all the data for 3.3x25.3.

\n

If the candidate does not use a ruler, award A0A1 where appropriate.

\n

 

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21M.2.SL.TZ1.2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Let fx=1+x for x>-1.

\n
\n

Show that f''x=-141+x3.

\n
[3]
\n
a.
\n
\n

Use mathematical induction to prove that fnx=-14n-12n-3!n-2!1+x12-n for n, n2.

\n
[9]
\n
b.
\n
\n

Let gx=emx, m.

\n

Consider the function h defined by hx=fx×gx for x>-1.

\n

It is given that the x2 term in the Maclaurin series for h(x) has a coefficient of 74.

\n

Find the possible values of m.

\n
[8]
\n
c.
\n
", "Markscheme": "
\n

attempt to use the chain rule            M1

\n

f'x=121+x-12         A1

\n

f''x=-141+x-32         A1

\n

=-141+x3         AG

\n

 

\n

Note: Award M1A0A0 for f'x=11+x or equivalent seen

\n

  

\n

[3 marks]

\n
a.
\n
\n

let n=2

\n

f''x=-141+x3=-1411!0!1+x12-2         R1

\n

 

\n

Note: Award R0 for not starting at n=2. Award subsequent marks as appropriate.

\n

 

\n

assume true for n=k, (so fkx=-14k-12k-3!k-2!1+x12-k)       M1

\n

 

\n

Note: Do not award M1 for statements such as “let n=k” or “n=k is true”. Subsequent marks can still be awarded.

\n

 

\n

consider n=k+1

\n

LHS=fk+1x=dfkxdx            M1

\n

=-14k-12k-3!k-2!12-k1+x12-k-1 (or equivalent)         A1

\n

 

\n

EITHER

\n

RHS=fk+1x=-14k2k-1!k-1!1+x12-k-1 (or equivalent)         A1

\n

=-14k2k-12k-22k-3!k-1k-2!1+x12-k-1        A1

\n

 

\n

Note: Award A1 for 2k-1!k-1!=2k-12k-22k-3!k-1k-2!=22k-12k-3!k-2!

\n

 

\n

=-14-14k-12k-12k-22k-3!k-1k-2!1+x12-k-1        A1

\n

=-12-14k-12k-12k-3!k-2!1+x12-k-1

\n

 

\n

Note: Award A1 for leading coefficient of -14.

\n

 

\n

=12-k-14k-12k-3!k-2!1+x12-k-1        A1

\n

 

\n

OR

\n

Note: The following A marks can be awarded in any order.

\n

 

\n

=-14k-12k-3!k-2!1-2k21+x12-k-1

\n

=-12-14k-12k-12k-3!k-2!1+x12-k-1        A1

\n

 

\n

Note: Award A1 for isolating (2k1) correctly.

\n

 

\n

=-12-14k-12k-1!2k-2k-2!1+x12-k-1        A1

\n

 

\n

Note: Award A1 for multiplying top and bottom by (k1) or 2(k1).

\n

 

\n

=-14-14k-12k-1!k-1k-2!1+x12-k-1        A1

\n

 

\n

Note: Award A1 for leading coefficient of -14.

\n

 

\n

=-14k2k-1!k-1!1+x12-k-1        A1

\n

 

\n

=-14k+1-12k+1-3!k+1-2!1+x12-k+1=RHS

\n

 

\n

THEN

\n

since true for n=2, and true for n=k+1 if true for n=k, the statement is true for all, n, n2  by mathematical induction           R1

\n

 

\n

Note: To obtain the final R1, at least four of the previous marks must have been awarded.

\n

 

\n

[9 marks]

\n
b.
\n
\n

METHOD 1

\n

hx=1+xemx

\n

using product rule to find h'x        (M1)

\n

h'x=1+xmemx+121+xemx         A1

\n

h''x=m1+xmemx+121+xemx+121+xmemx-141+x3emx         A1

\n

substituting x=0 into h''x       M1

\n

h''0=m2+12m+12m-14=m2+m-14         A1

\n

hx=h0+xh'0+x22!h''0+

\n

equating x2 coefficient to 74       M1

\n

h''02!=74 h''0=72

\n

4m2+4m-15=0         A1

\n

2m+52m-3=0

\n

m=-52  or  m=32         A1

\n

 

\n

METHOD 2

\n

EITHER

\n

attempt to find f0, f'0, f''0        (M1)

\n

fx=1+x12                    f0=1

\n

f'x=121+x-12            f'0=12

\n

f''x=-141+x-32      f''0=-14

\n

fx=1+12x-18x2+         A1

\n

 

\n

OR

\n

attempt to apply binomial theorem for rational exponents        (M1)

\n

fx=1+x12=1+12x+12-122!x2

\n

fx=1+12x-18x2+         A1

\n

 

\n

THEN

\n

gx=1+mx+m22x2+        (A1)

\n

hx=1+12x-18x2+1+mx+m22x2+        (M1)

\n

coefficient of x2 is m22+m2-18         A1

\n

attempt to set equal to 74 and solve             M1

\n

m22+m2-18=74

\n

4m2+4m-15=0          A1

\n

2m+52m-3=0

\n

m=-52  or  m=32         A1

\n

 

\n

METHOD 3

\n

g'x=memx and g''x=m2emx        (A1)

\n

hx=h0+xh'0+x22!h''0+

\n

equating x2 coefficient to 74       M1

\n

h''02!=74 h''0=72

\n

using product rule to find h'x and h''x        (M1)

\n

h'x=fxg'x+f'xgx

\n

h''x=fxg''x+2f'xg'x+f''xgx         A1

\n

substituting x=0 into h''x       M1

\n

h''0=f0g''0+2g'0f'0+g0f''0

\n

=1×m2+2m×12+1×-14  =m2+m-14         A1

\n

4m2+4m-15=0          A1

\n

2m+52m-3=0

\n

m=-52  or  m=32         A1

\n

 

\n

[8 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.1.AHL.TZ1.12", "topics": [ "topic-3-geometry-and-trigonometry", "topic-5-calculus" ], "subtopics": [ "sl-3-6-pythagorean-identity-double-angles", "ahl-5-12-first-principles-higher-derivatives", "ahl-5-19-maclaurin-series" ] }, { "Question": "
\n

A florist sells bouquets of roses. The florist recorded, in Table 1, the number of roses in each bouquet sold to customers.

\n

Table 1

\n

\n

The roses can be arranged into bouquets of size small, medium or large. The data from Table 1 has been organized into a cumulative frequency table, Table 2.

\n

Table 2

\n

\n
\n

Complete the cumulative frequency table.

\n
[2]
\n
a.
\n
\n

Write down the probability that a bouquet of roses sold is not small.

\n
[2]
\n
b.
\n
\n

A customer buys a large bouquet.

\n

Find the probability that there are 12 roses in this bouquet.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

     (A1)(A1)(ft) (C2)

\n

Note: Award (A1) for 10; (A1)(ft) for the last column all correct. Follow through from their 10 for their 50 in the last column.

\n

[2 marks]

\n
a.
\n
\n

\n\n\n35\n\n\n50\n\n\n\n\n\n(\n\n0.7\n\n,\n\n\n\n\n7\n\n10\n\n\n\n,\n\n\n\n70\n\n\n\n\n\n)\n\n    (A1)(ft)(A1)(ft) (C2)

\n

Note: Award (A1)(ft) for their numerator being 25 + their 10, and (A1)(ft) for their denominator being their 50. Follow through from part (a).

\n

[2 marks]

\n
b.
\n
\n

\n\n4\n\n10\n\n\n\n\n\n(\n\n0.4\n\n,\n\n\n\n\n2\n5\n\n\n,\n\n\n\n40\n\n\n\n\n\n)\n\n   (A1)(A1)(ft) (C2)

\n

Note: Award (A1) for a numerator of 4 and (A1)(ft) for their 10 as denominator. Follow through from part (a).

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ1.T_5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n2\n\n\nsin\n\n\n(\n\n3\nx\n\n)\n\n+\n4\n for \nx\n\n\nR\n\n.

\n
\n

Let \ng\n\n(\nx\n)\n\n=\n5\nf\n\n(\n\n2\nx\n\n)\n\n.

\n
\n

The function \ng\n can be written in the form \ng\n\n(\nx\n)\n\n=\n10\n\n\nsin\n\n\n(\n\nb\nx\n\n)\n\n+\nc\n.

\n
\n

The range of \nf\n is \nk\n\nf\n\n(\nx\n)\n\n\nm\n. Find \nk\n and \nm\n.

\n
[3]
\n
a.
\n
\n

Find the range of \ng\n.

\n
[2]
\n
b.
\n
\n

Find the value of \nb\n and of \nc\n.

\n
[3]
\n
c.i.
\n
\n

Find the period of \ng\n.

\n
[2]
\n
c.ii.
\n
\n

The equation \ng\n\n(\nx\n)\n\n=\n12\n has two solutions where \nπ\n ≤ \nx\n ≤ \n\n\n\n4\nπ\n\n3\n\n\n. Find both solutions.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid attempt to find range   (M1)

\n

eg  ,  max = 6   min = 2,

\n

\n2\n\n\nsin\n\n\n(\n\n3\n×\n\nπ\n6\n\n\n)\n\n+\n4\n and \n2\n\n\nsin\n\n\n(\n\n3\n×\n\nπ\n2\n\n\n)\n\n+\n4\n ,   \n2\n\n(\n1\n)\n\n+\n4\n and \n2\n\n(\n\n\n1\n\n)\n\n+\n4\n,

\n

\nk\n=\n2\n\nm\n=\n6\n      A1A1 N3

\n

[3 marks]

\n
a.
\n
\n

10 ≤ \ny\n ≤ 30      A2 N2

\n

[2 marks]

\n
b.
\n
\n

evidence of substitution (may be seen in part (b))       (M1)

\n

eg   \n5\n\n(\n\n2\n\n\nsin\n\n\n(\n\n\n3\n\n\n(\n\n2\nx\n\n)\n\n\n)\n\n+\n4\n\n)\n\n\n\n\n3\n\n\n(\n\n2\nx\n\n)\n\n\n 

\n

\nb\n=\n6\n\nc\n=\n20\n   (accept \n10\n\n\nsin\n\n\n(\n\n6\nx\n\n)\n\n+\n20\n )     A1A1 N3

\n

Note: If no working shown, award N2 for one correct value.

\n

[3 marks]

\n
c.i.
\n
\n

correct working      (A1)

\n

eg   \n\n\n2\nπ\n\nb\n\n

\n

1.04719

\n

\n\n\n2\nπ\n\n6\n\n\n\n\n\n(\n\n=\n\nπ\n3\n\n\n)\n\n, 1.05     A1 N2

\n

[2 marks]

\n
c.ii.
\n
\n

valid approach     (M1)

\n

eg   \n\nsi\n\n\n\n\nn\n\n\n\n1\n\n\n\n\n(\n\n\n\n8\n\n10\n\n\n\n)\n\n\n\n\n6\nx\n=\n\n0.927\n\n\n\n\n0.154549\n\n\n\nx\n=\n0.678147\n

\n

Note: Award M1 for any correct value for \nx\n or \n6\nx\n which lies outside the domain of \nf\n.

\n

3.81974,  4.03424

\n

\nx\n=\n3.82\n,  \nx\n=\n4.03\n  (do not accept answers in degrees)     A1A1 N3

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.2.SL.TZ1.S_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

A company produces bags of sugar whose masses, in grams, can be modelled by a normal distribution with mean 1000 and standard deviation 3.5. A bag of sugar is rejected for sale if its mass is less than 995 grams.

\n
\n

Find the probability that a bag selected at random is rejected.

\n
[2]
\n
a.
\n
\n

Estimate the number of bags which will be rejected from a random sample of 100 bags.

\n
[1]
\n
b.
\n
\n

Given that a bag is not rejected, find the probability that it has a mass greater than 1005 grams.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

Note: In this question, do not penalise incorrect use of strict inequality signs.

\n

Let X= mass of a bag of sugar

\n

 

\n

evidence of identifying the correct area          (M1)

\n

PX<995=0.0765637

\n

=0.0766          A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

Note: In this question, do not penalise incorrect use of strict inequality signs.

\n

Let X= mass of a bag of sugar

\n

 

\n

0.0766×100

\n

8          A1

\n

 

\n

Note: Accept 7.66.

\n

 

\n

[1 mark]

\n
b.
\n
\n

Note: In this question, do not penalise incorrect use of strict inequality signs.

\n

Let X= mass of a bag of sugar

\n

 

\n

recognition that PX>1005X995  is required         (M1)

\n

PX995X>1005PX995

\n

PX>1005PX995         (A1)

\n

0.07656371-0.0765637=0.07656370.923436

\n

=0.0829        A1

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.2.SL.TZ1.3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations", "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A particle moves in a straight line. The velocity, vms-1, of the particle at time t seconds is given by v(t)=tsint-3, for 0t10.

\n

The following diagram shows the graph of v.

\n

\n
\n

Find the smallest value of t for which the particle is at rest.

\n
[2]
\n
a.
\n
\n

Find the total distance travelled by the particle.

\n
[2]
\n
b.
\n
\n

Find the acceleration of the particle when t=7.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

recognising v=0         (M1)

\n

t=6.74416

\n

=6.74 (sec)         A1

\n

 

\n

Note: Do not award A1 if additional values are given.

\n

 

\n

[2 marks]

\n
a.
\n
\n

010vtdt  OR  -06.74416vtdt+6.744169.08837vtdt-9.0883710vtdt         (A1)

\n

=37.0968

\n

=37.1 m         A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

recognizing acceleration at t=7 is given by v'7         (M1)

\n

acceleration =5.93430

\n

=5.93 ms-2         A1

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.2.SL.TZ1.5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

A Ferris wheel with diameter 110 metres rotates at a constant speed. The lowest point on the wheel is 10 metres above the ground, as shown on the following diagram. P is a point on the wheel. The wheel starts moving with P at the lowest point and completes one revolution in 20 minutes.

\n

\n

The height, h metres, of P above the ground after t minutes is given by h(t)=acos(bt)+c, where a, b, c  .

\n

Find the values of a, b and c.

\n
", "Markscheme": "
\n

amplitude is 1102=55          (A1)

\n

a=-55          A1

\n

c=65          A1

\n

2πb=20  OR  -55cos20b+65=10          (M1)

\n

b=π10=0.314          A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.2.SL.TZ1.4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

The following diagram shows the graph of \nf\n(\nx\n)\n=\na\nsin\n\nb\nx\n+\nc\n, for \n0\n\nx\n\n12\n.

\n

\"N16/5/MATME/SP2/ENG/TZ0/10\"

\n

The graph of \nf\n has a minimum point at \n(\n3\n,\n\n \n\n5\n)\n and a maximum point at \n(\n9\n,\n\n \n\n17\n)\n.

\n
\n

The graph of \ng\n is obtained from the graph of \nf\n by a translation of \n\n(\n\n\n\n\nk\n\n\n\n\n0\n\n\n\n\n)\n\n. The maximum point on the graph of \ng\n has coordinates \n(\n11.5\n,\n\n \n\n17\n)\n.

\n
\n

The graph of \ng\n changes from concave-up to concave-down when \nx\n=\nw\n.

\n
\n

(i)     Find the value of c .

\n

(ii)     Show that b = π 6 .

\n

(iii)     Find the value of a .

\n
[6]
\n
a.
\n
\n

(i)     Write down the value of k .

\n

(ii)     Find g ( x ) .

\n
[3]
\n
b.
\n
\n

(i)     Find w .

\n

(ii)     Hence or otherwise, find the maximum positive rate of change of g .

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

(i)     valid approach     (M1)

\n

eg 5 + 17 2

\n

c = 11    A1     N2

\n

(ii)     valid approach     (M1)

\n

eg period is 12, per  = 2 π b ,   9 3

\n

b = 2 π 12    A1

\n

b = π 6      AG     N0

\n

(iii)     METHOD 1

\n

valid approach     (M1)

\n

eg 5 = a sin ( π 6 × 3 ) + 11 , substitution of points

\n

a = 6      A1     N2

\n

METHOD 2

\n

valid approach     (M1)

\n

eg 17 5 2 , amplitude is 6

\n

a = 6      A1     N2

\n

[6 marks]

\n
a.
\n
\n

(i)     k = 2.5      A1     N1

\n

(ii)     g ( x ) = 6 sin ( π 6 ( x 2.5 ) ) + 11      A2     N2

\n

[3 marks]

\n
b.
\n
\n

(i)     METHOD 1 Using g

\n

recognizing that a point of inflexion is required     M1

\n

eg sketch, recognizing change in concavity

\n

evidence of valid approach     (M1)

\n

eg g ( x ) = 0 , sketch, coordinates of max/min on  g

\n

w = 8.5 (exact)     A1     N2

\n

METHOD 2 Using f

\n

recognizing that a point of inflexion is required     M1

\n

eg sketch, recognizing change in concavity

\n

evidence of valid approach involving translation     (M1)

\n

eg x = w k , sketch,  6 + 2.5

\n

w = 8.5  (exact)     A1     N2

\n

(ii)     valid approach involving the derivative of g or f (seen anywhere)     (M1)

\n

eg g ( w ) ,   π cos ( π 6 x ) , max on derivative, sketch of derivative

\n

attempt to find max value on derivative     M1

\n

eg π cos ( π 6 ( 8.5 2.5 ) ) ,   f ( 6 ) , dot on max of sketch

\n

3.14159

\n

max rate of change = π  (exact), 3.14     A1     N2

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.2.SL.TZ0.S_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

Consider the expansion of (3+x2)n+1, where n+ .

\n

Given that the coefficient of x4 is 20412, find the value of n.

\n
", "Markscheme": "
\n

METHOD 1

\n

product of a binomial coefficient, a power of 3 (and a power of x2) seen         (M1)

\n

evidence of correct term chosen           (A1)

\n

C2n+1×3n+1-2×x22 =nn+12×3n-1×x4  OR  n-r=1

\n

equating their coefficient to 20412 or their term to 20412x4         (M1)

\n

 

\n

EITHER

\n

C2n+1×3n-1=20412           (A1)

\n

 

\n

OR

\n

Crr+2×3r=20412r=6           (A1)

\n

 

\n

THEN

\n

n=7         A1

\n

 

\n


METHOD 2

\n

3n+11+x23n+1

\n

product of a binomial coefficient, and a power of x23  OR  13 seen         (M1)

\n

evidence of correct term chosen           (A1)

\n

3n+1×nn+12!×x232 =3n-12nn+1x4 

\n

equating their coefficient to 20412 or their term to 20412x4         (M1)

\n

3n-1×nn+12=20412           (A1)

\n

n=7         A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.2.SL.TZ1.6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Two friends Amelia and Bill, each set themselves a target of saving $20000. They each have $9000 to invest.

\n
\n

Amelia invests her $9000 in an account that offers an interest rate of 7% per annum compounded annually.

\n
\n

A third friend Chris also wants to reach the $20000 target. He puts his money in a safe where he does not earn any interest. His system is to add more money to this safe each year. Each year he will add half the amount added in the previous year.

\n
\n

Find the value of Amelia’s investment after 5 years to the nearest hundred dollars.

\n
[3]
\n
a.i.
\n
\n

Determine the number of years required for Amelia’s investment to reach the target.

\n
[2]
\n
a.ii.
\n
\n

Bill invests his $9000 in an account that offers an interest rate of r% per annum compounded monthly, where r is set to two decimal places.

\n

Find the minimum value of r needed for Bill to reach the target after 10 years.

\n
[3]
\n
b.
\n
\n

Show that Chris will never reach the target if his initial deposit is $9000.

\n
[5]
\n
c.i.
\n
\n

Find the amount Chris needs to deposit initially in order to reach the target after 5 years. Give your answer to the nearest dollar.

\n
[3]
\n
c.ii.
\n
", "Markscheme": "
\n

EITHER

\n

9000×1+71005           (A1)

\n

12622.965           (A1)

\n

 

\n

OR

\n

n=5
I%=7
PV=9000
P/Y=1
C/Y=1           (A1)
±12622.965           (A1)

\n

 

\n

THEN

\n

($)12600           A1

\n

 

\n

[3 marks]

\n
a.i.
\n
\n

EITHER

\n

90001+7100x=20000           (A1)

\n

 

\n

OR

\n

I%=7
PV=9000
FV=±20000
P/Y=1
C/Y=1           (A1)

\n

 

\n

THEN

\n

=12 (years)           A1

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

METHOD 1

\n

attempt to substitute into compound interest formula (condone absence of compounding periods)           (M1)

\n

90001+r100×1212×10=20000

\n

8.01170           (A1)

\n

r=8.02%           A1

\n

 

\n

METHOD 2

\n

n=10
PV=±9000
FV=20000
P/Y=1
C/Y=12
r=8.01170           (M1)(A1)

\n

 

\n

Note: Award M1 for an attempt to use a financial app in their technology, award A1 for ( r=) 8.01170

\n

 

\n

r=8.02%           A1

\n

 

\n

[3 marks]

\n
b.
\n
\n

recognising geometric series (seen anywhere)           (M1)

\n

r=45009000 =12           (A1)

\n

 

\n

EITHER

\n

considering S           (M1)

\n

90001-0.5=18000           A1

\n

correct reasoning that 18000<20000           R1

\n

 

\n

Note: Accept S<20000 only if S has been calculated.

\n

 

\n

OR

\n

considering Sn for a large value of n, n80           (M1)

\n

 

\n

Note: Award M1 only if the candidate gives a valid reason for choosing a value of n, where 50n<80.

\n

 

\n

correct value of Sn for their n           A1

\n

valid reason why Chris will not reach the target, which involves their choice of n, their value of Sn and Chris’ age OR using two large values of n to recognize asymptotic behaviour of Sn as n.           R1

\n

 

\n

Note: Do not award the R mark without the preceding A mark.

\n

 

\n

THEN

\n

Therefore, Chris will never reach the target.           AG

\n

 

\n

[5 marks]

\n
c.i.
\n
\n

recognising geometric sum           M1

\n

u11-0.550.5=20000           (A1)

\n

10322.58

\n

($)10323           A1

\n

 

\n

[3 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "21M.2.SL.TZ1.7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

Note: In this question, distance is in metres and time is in seconds.

\n

Two particles \n\n\nP\n1\n\n\n and \n\n\nP\n2\n\n\n start moving from a point A at the same time, along different straight lines.

\n

After \nt\n seconds, the position of \n\n\nP\n1\n\n\n is given by r = \n\n(\n\n\n\n\n4\n\n\n\n\n\n\n1\n\n\n\n\n\n3\n\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n1\n\n\n\n\n2\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n.

\n
\n

Two seconds after leaving A, \n\n\nP\n1\n\n\n is at point B.

\n
\n

Two seconds after leaving A, \n\n\nP\n2\n\n\n is at point C, where \n\n\nAC\n\n\n\n=\n\n(\n\n\n\n\n3\n\n\n\n\n0\n\n\n\n\n4\n\n\n\n\n)\n\n.

\n
\n

Find the coordinates of A.

\n
[2]
\n
a.
\n
\n

Find  AB ;

\n
[3]
\n
b.i.
\n
\n

Find  | AB | .

\n
[2]
\n
b.ii.
\n
\n

Find cos B A ^ C .

\n
[5]
\n
c.
\n
\n

Hence or otherwise, find the distance between P 1 and P 2 two seconds after they leave A.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

recognizing t = 0 at A     (M1)

\n

A is ( 4 ,   1 ,   3 )     A1     N2

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

valid approach     (M1)

\n

eg ( 4 1 3 ) + 2 ( 1 2 2 ) ,   ( 6 ,   3 ,   1 )

\n

correct approach to find AB     (A1)

\n

eg AO + OB ,  B A,  ( 6 3 1 ) ( 4 1 3 )

\n

AB = ( 2 4 4 )     A1     N2

\n

METHOD 2

\n

recognizing AB is two times the direction vector     (M1)

\n

correct working     (A1)

\n

eg AB = 2 ( 1 2 2 )

\n

AB = ( 2 4 4 )     A1     N2

\n

[3 marks]

\n
b.i.
\n
\n

correct substitution     (A1)

\n

eg | AB | = 2 2 + 4 2 + 4 2 ,   4 + 16 + 16 ,   36

\n

| AB | = 6     A1     N2

\n

[2 marks]

\n
b.ii.
\n
\n

METHOD 1 (vector approach)

\n

valid approach involving AB and AC     (M1)

\n

eg AB AC ,   BA AC AB × AC

\n

finding scalar product and | AC |     (A1)(A1)

\n

scalar product 2 ( 3 ) + 4 ( 0 ) 4 ( 4 )   ( = 10 )

\n

| AC | = 3 2 + 0 2 + 4 2   ( = 5 )

\n

substitution of their scalar product and magnitudes into cosine formula     (M1)

\n

eg cos B A ^ C = 6 + 0 16 6 3 2 + 4 2

\n

cos B A ^ C = 10 30 ( = 1 3 )     A1     N2

\n

 

\n

METHOD 2 (triangle approach)

\n

valid approach involving cosine rule     (M1)

\n

eg cos B A ^ C = A B 2 + A C 2 B C 2 2 × AB × AC

\n

finding lengths AC and BC     (A1)(A1)

\n

AC = 5 ,  BC = 9

\n

substitution of their lengths into cosine formula     (M1)

\n

eg cos B A ^ C = 5 2 + 6 2 9 2 2 × 5 × 6

\n

cos B A ^ C = 20 60   ( = 1 3 )     A1     N2

\n

[5 marks]

\n
c.
\n
\n

Note:     Award relevant marks for working seen to find BC in part (c) (if cosine rule used in part (c)).

\n

 

\n

METHOD 1 (using cosine rule)

\n

recognizing need to find BC     (M1)

\n

choosing cosine rule     (M1)

\n

eg c 2 = a 2 + b 2 2 a b cos C

\n

correct substitution into RHS     A1

\n

eg B C 2 = ( 6 ) 2 + ( 5 ) 2 2 ( 6 ) ( 5 ) ( 1 3 ) ,   36 + 25 + 20

\n

distance is 9     A1     N2

\n

 

\n

METHOD 2 (finding magnitude of B C

\n

recognizing need to find BC     (M1)

\n

valid approach     (M1)

\n

eg attempt to find O B or O C , O B = ( 6 3 1 ) or O C = ( 7 1 7 ) ,   B A + A C

\n

correct working     A1

\n

eg B C = ( 1 4 8 ) ,   C B = ( 1 4 8 ) ,   1 2 + 4 2 + 8 2 = 81

\n

distance is 9     A1     N2

\n

 

\n

METHOD 3 (finding coordinates and using distance formula)

\n

recognizing need to find BC     (M1)

\n

valid approach     (M1)

\n

eg attempt to find coordinates of B or C, B ( 6 ,   3 ,   1 ) or C ( 7 ,   1 ,   7 )

\n

correct substitution into distance formula     A1

\n

eg BC = ( 6 7 ) 2 + ( 3 ( 1 ) ) 2 + ( 1 7 ) 2 ,   1 2 + 4 2 + 8 2 = 81

\n

distance is 9     A1     N2

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.1.SL.TZ2.S_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

In a high school, 160 students completed a questionnaire which asked for the number of people they are following on a social media website. The results were recorded in the following box-and-whisker diagram.

\n

\n
\n

The following incomplete table shows the distribution of the responses from these 160 students.

\n

\n
\n

Write down the median.

\n
[1]
\n
a.
\n
\n

Complete the table.

\n
[2]
\n
b.
\n
\n

Write down the mid-interval value for the 100 < x ≤ 150 group.

\n
[1]
\n
c.i.
\n
\n

Using the table, calculate an estimate for the mean number of people being followed on the social media website by these 160 students.

\n
[2]
\n
c.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

180   (A1) (C1)
[1 mark]

\n
a.
\n
\n

36, 24     (A1)(A1) (C2)

\n

Note: Award (A0)(A1) for two incorrect values that add up to 60.

\n

[2 marks]

\n
b.
\n
\n

125 (accept 125.5)     (A1)

\n
c.i.
\n
\n

\n\n\n4\n×\n25\n+\n36\n×\n75\n+\n34\n×\n125\n+\n46\n×\n175\n+\n24\n×\n225\n+\n16\n×\n275\n\n\n160\n\n\n     (M1)

\n

Note: Award (M1) for correct substitution of their mid-interval values, multiplied by their frequencies, into mean formula.

\n

=156 (155.625)     (A1)(ft) (C3)

\n

Note: Follow through from parts (b) and (c)(i).

\n

[3 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "18M.1.SL.TZ1.T_6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

The following diagram shows the quadrilateral ABCD.

\n

\n

AB = 6.73 cm, BC = 4.83 cm, BĈD = 78.2° and CD = 3.80 cm.

\n
\n

Find BD.

\n
[3]
\n
a.
\n
\n

The area of triangle ABD is 18.5 cm2. Find the possible values of θ.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

choosing cosine rule        (M1)

\n

eg   \n\n\nc\n2\n\n\n=\n\n\na\n2\n\n\n+\n\n\nb\n2\n\n\n\n2\na\nb\n\n\ncos\n\n\nC\n

\n

correct substitution into RHS       (A1)

\n

eg   \n\n\n4.83\n2\n\n\n+\n\n\n3.80\n2\n\n\n\n2\n×\n4.83\n×\n3.80\n×\n\ncos\n\n\n78.2\n\n30.2622\n,

\n

\n\n\n4.83\n2\n\n\n+\n\n\n3.80\n2\n\n\n\n2\n\n(\n\n4.83\n\n)\n\n\n(\n\n3.80\n\n)\n\n×\n\ncos\n\n\n1.36\n

\n

5.50111

\n

5.50 (cm)     A1 N2

\n

[3 marks]

\n
a.
\n
\n

correct substitution for area of triangle ABD       (A1)

\n

eg   \n\n1\n2\n\n×\n6.73\n×\n5.50111\n\n\nsin\n\n\nθ\n

\n

correct equation      A1

\n

eg   \n\n1\n2\n\n×\n6.73\n×\n5.50111\n\n\nsin\n\n\nθ\n=\n18.5\n ,  \n\nsin\n\n\nθ\n=\n\n0\n\n\n.999393\n\n

\n

88.0023,  91.9976,  1.53593,  1.60566

\n

θ = 88.0 (degrees) or 1.54 (radians)

\n

θ = 92.0 (degrees) or 1.61 (radians)    A1A1 N2

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.SL.TZ2.S_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The following diagram shows a triangle ABC.

\n

\"N17/5/MATME/SP2/ENG/TZ0/01\"

\n

\n\nAB\n\n=\n5\n\n\nc\nm\n,\nC\n\n\nA\n^\n\n\nB\n\n\n=\n 50° and \n\n\nA\n\n\nC\n^\n\n\nB\n\n\n=\n 112°

\n
\n

Find BC.

\n
[3]
\n
a.
\n
\n

Find the area of triangle ABC.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of choosing sine rule     (M1)

\n

eg sin A a = sin B b

\n

correct substitution     (A1)

\n

eg BC sin 50 = 5 sin 112

\n

4.13102

\n

BC = 4.13  (cm)     A1     N2

\n

[3 marks]

\n
a.
\n
\n

correct working     (A1)

\n

eg B ^ = 180 50 112 , 18°, AC = 1.66642

\n

correct substitution into area formula     (A1)

\n

eg 1 2 × 5 × 4.13 × sin 18 ,   0.5 ( 5 ) ( 1.66642 ) sin 50 ,   1 2 ( 4.13 ) ( 1.66642 ) sin 112

\n

3.19139

\n

area = 3.19  (c m 2 )     A1     N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.2.SL.TZ0.S_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Two straight fences meet at point A and a field lies between them.

\n

A horse is tied to a post, P, by a rope of length r metres. Point D is on one fence and point E is on the other, such that PD=PE=PA=r and DP^E=θ radians. This is shown in the following diagram.

\n

\n

The length of the arc DE shown in the diagram is 28m.

\n
\n

A new fence is to be constructed between points B and C which will enclose the field, as shown in the following diagram.

\n

\n

Point C is due west of B and AC=800m . The bearing of B from A is 195°.

\n
\n

Write down an expression for r in terms of θ.

\n
[1]
\n
a.
\n
\n

Show that the area of the field that the horse can reach is 392θ2θ+sinθ.

\n
[4]
\n
b.
\n
\n

The area of field that the horse can reach is 460m2. Find the value of θ.

\n
[2]
\n
c.
\n
\n

Hence, find the size of DA^E.

\n
[2]
\n
d.
\n
\n

Find the size of AB^C.

\n
[2]
\n
e.i.
\n
\n

Find the length of new fence required.

\n
[3]
\n
e.ii.
\n
", "Markscheme": "
\n

r=28θ           A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

recognising sum of area of sector and area of triangle required           (M1)

\n

12r2θ+12r×r×sinπ-θ =r22(θ+sinπ-θ           A1

\n

sinπ-θ=sinθ (substitution seen anywhere)           A1

\n

1228θ2θ+1228θ2sinθ  OR  1228θ2θ+sinθ           A1

\n

area=392θ2θ+sinθ           AG

\n

 

\n

[4 marks]

\n
b.
\n
\n

392θ2θ+sinθ=460           (M1)

\n

θ=1.43917

\n

θ=1.44           A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

π-π-θ2  OR  θ2           (M1)

\n

DA^E=0.719588

\n

DA^E=0.720           A1

\n

 

\n

[2 marks]

\n
d.
\n
\n

AB^C=195-180+90           (A1)

\n

=105°           A1

\n

 

\n

[2 marks]

\n
e.i.
\n
\n

choosing sine rule          (M1)

\n

BCsin DA^E=800sin105  OR  BCsin DA^E=800sin1.83          A1

\n

BC=546m           A1

\n

 

\n

[2 marks]

\n
e.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
", "question_id": "21M.2.SL.TZ1.8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Let \n\n\nAB\n\n\n\n=\n\n(\n\n\n\n\n4\n\n\n\n\n1\n\n\n\n\n2\n\n\n\n\n)\n\n.

\n
\n

Find \n\n|\n\n\n\nAB\n\n\n\n\n|\n\n.

\n
[2]
\n
a.
\n
\n

Let \n\n\nAC\n\n\n\n=\n\n(\n\n\n\n\n3\n\n\n\n\n0\n\n\n\n\n0\n\n\n\n\n)\n\n. Find \n\n\nB\n\n\nA\n^\n\n\nC\n\n\n.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct substitution     (A1)

\n

eg\n\n\n\n\n\n\n\n\n\n4\n2\n\n\n+\n\n\n1\n2\n\n\n+\n\n\n2\n2\n\n\n\n

\n

4.58257

\n

\n\n|\n\n\n\nAB\n\n\n\n\n|\n\n=\n\n21\n\n (exact), 4.58     A1     N2

\n

[2 marks]

\n
a.
\n
\n

finding scalar product and \n\n|\n\n\n\nAC\n\n\n\n\n|\n\n     (A1)(A1)

\n

scalar product \n=\n(\n4\n×\n3\n)\n+\n(\n1\n×\n0\n)\n+\n(\n2\n×\n0\n)\n\n \n\n(\n=\n12\n)\n

\n

\n\n|\n\n\n\nAC\n\n\n\n\n|\n\n=\n\n\n\n3\n2\n\n\n+\n0\n+\n0\n\n\n \n\n(\n=\n3\n)\n

\n

substituting their values into cosine formula     (M1)

\n

eg cos B\n\n\nA\n^\n\n\nC\n\n = \n\n\n\n4\n×\n3\n+\n0\n+\n0\n\n\n\n\n\n3\n2\n\n\n\n×\n\n21\n\n\n\n,\n\n \n\n\n4\n\n\n21\n\n\n\n,\n\n \n\ncos\n\nθ\n=\n0.873\n

\n

0.509739 (29.2059°)

\n

\n\n\nB\n\n\nA\n^\n\n\nC\n\n\n=\n0.510\n (29.2°)     A1     N2

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.2.SL.TZ0.S_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

A line \nL\n passes through points \n\nA\n\n(\n\n3\n,\n\n \n\n4\n,\n\n \n\n2\n)\n and \n\nB\n\n(\n\n1\n,\n\n \n\n3\n,\n\n \n\n3\n)\n.

\n
\n

The line \nL\n also passes through the point \n\nC\n\n(\n3\n,\n\n \n\n1\n,\n\n \n\np\n)\n.

\n
\n

Show that AB = ( 2 1 1 ) .

\n
[1]
\n
a.i.
\n
\n

Find a vector equation for L .

\n
[2]
\n
a.ii.
\n
\n

Find the value of p .

\n
[5]
\n
b.
\n
\n

The point D has coordinates ( q 2 ,   0 ,   q ) . Given that DC is perpendicular to L , find the possible values of q .

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

correct approach     A1

\n

 

\n

eg ( 1 3 3 ) ( 3 4 2 ) ,   ( 3 4 2 ) + ( 1 3 3 )

\n

 

\n

AB = ( 2 1 1 )     AG     N0

\n

[1 mark]

\n
a.i.
\n
\n

any correct equation in the form r = a + t b (any parameter for t )

\n

 

\n

where a is  ( 3 4 2 )  or  ( 1 3 3 )  and b is a scalar multiple of  ( 2 1 1 )     A2     N2

\n

 

\n

eg r = ( 3 4 2 ) + t ( 2 1 1 ) ,   ( x ,   y ,   z ) = ( 1 ,   3 ,   3 ) + s ( 2 ,   1 ,   1 ) ,   r = ( 3 + 2 t 4 t 2 + t )

\n

 

\n

Note:     Award A1 for the form a + t b , A1 for the form L = a + t b , A0 for the form r = b + t a .

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

METHOD 1 – finding value of parameter

\n

valid approach     (M1)

\n

 

\n

eg ( 3 4 2 ) + t ( 2 1 1 ) = ( 3 1 p ) ,   ( 1 ,   3 ,   3 ) + s ( 2 ,   1 ,   1 ) = ( 3 ,   1 ,   p )

\n

 

\n

one correct equation (not involving p )     (A1)

\n

eg 3 + 2 t = 3 ,   1 2 s = 3 ,   4 t = 1 ,   3 + s = 1

\n

correct parameter from their equation (may be seen in substitution)     A1

\n

eg t = 3 ,   s = 2

\n

correct substitution     (A1)

\n

 

\n

eg ( 3 4 2 ) + 3 ( 2 1 1 ) = ( 3 1 p ) ,   3 ( 2 )

\n

 

\n

p = 5 ( accept  ( 3 1 5 ) )     A1     N2

\n

 

\n

METHOD 2 – eliminating parameter

\n

valid approach     (M1)

\n

 

\n

eg ( 3 4 2 ) + t ( 2 1 1 ) = ( 3 1 p ) ,   ( 1 ,   3 ,   3 ) + s ( 2 ,   1 ,   1 ) = ( 3 ,   1 ,   p )

\n

 

\n

one correct equation (not involving p )     (A1)

\n

eg 3 + 2 t = 3 ,   1 2 s = 3 ,   4 t = 1 ,   3 + s = 1

\n

correct equation (with p )     A1

\n

eg 2 + t = p ,   3 s = p

\n

correct working to solve for p     (A1)

\n

eg 7 = 2 p 3 ,   6 = 1 + p

\n

 

\n

p = 5 ( accept  ( 3 1 5 ) )     A1     N2

\n

 

\n

[5 marks]

\n
b.
\n
\n

valid approach to find DC or CD     (M1)

\n

 

\n

eg ( 3 1 5 ) ( q 2 0 q ) ,   ( q 2 0 q ) ( 3 1 5 ) ,   ( q 2 0 q ) ( 3 1 p )

\n

 

\n

correct vector for DC or CD  (may be seen in scalar product)     A1

\n

 

\n

eg ( 3 q 2 1 5 q ) ,   ( q 2 3 1 q 5 ) ,   ( 3 q 2 1 p q )

\n

 

\n

recognizing scalar product of DC or CD with direction vector of L is zero (seen anywhere)     (M1)

\n

 

\n

eg ( 3 q 2 1 p q ) ( 2 1 1 ) = 0 ,   DC AC = 0 ,   ( 3 q 2 1 5 q ) ( 2 1 1 ) = 0

\n

 

\n

correct scalar product in terms of only q     A1

\n

eg 6 2 q 2 1 + 5 q ,   2 q 2 + q 10 = 0 ,   2 ( 3 q 2 ) 1 + 5 q

\n

correct working to solve quadratic     (A1)

\n

eg ( 2 q + 5 ) ( q 2 ) ,   1 ± 1 4 ( 2 ) ( 10 ) 2 ( 2 )

\n

q = 5 2 ,   2     A1A1     N3

\n

 

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.1.SL.TZ0.S_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

Point A has coordinates (−4, −12, 1) and point B has coordinates (2, −4, −4).

\n
\n

The line L passes through A and B.

\n
\n

Show that \n\n\n\nAB\n\n\n\n\n=\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n

\n
[1]
\n
a.
\n
\n

Find a vector equation for L.

\n
[2]
\n
b.i.
\n
\n

Point C (k , 12 , −k) is on L. Show that k = 14.

\n
[4]
\n
b.ii.
\n
\n

Find \n\n\n\nOB\n\n\n\n\n\n\n\n\n\nAB\n\n\n\n\n.

\n
[2]
\n
c.i.
\n
\n

Write down the value of angle OBA.

\n
[1]
\n
c.ii.
\n
\n

Point D is also on L and has coordinates (8, 4, −9).

\n

Find the area of triangle OCD.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct approach       A1

\n

eg   \n\n\n\nAO\n\n\n\n\n\n\n+\n\n\n\n\n\nOB\n\n\n\n\n,\n\n\n\n\nB\n\n\n\nA\n\n\n\n\n\n\n\n(\n\n\n\n\n\n2\n\n\n\n\n\n4\n\n\n\n\n\n4\n\n\n\n)\n\n\n\n(\n\n\n\n\n\n4\n\n\n\n\n\n12\n\n\n\n\n\n\n\n1\n\n\n\n)\n\n

\n

\n\n\n\nAB\n\n\n\n\n=\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n     AG  N0

\n

[1 mark]

\n
a.
\n
\n

any correct equation in the form r = a + tb (any parameter for t)      A2 N2

\n

where a is \n\n(\n\n\n\n\n\n2\n\n\n\n\n\n4\n\n\n\n\n\n4\n\n\n\n)\n\n or \n\n(\n\n\n\n\n\n4\n\n\n\n\n\n12\n\n\n\n\n\n\n\n1\n\n\n\n)\n\n and b is a scalar multiple of \n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n

\n

eg  r \n=\n\n(\n\n\n\n\n\n4\n\n\n\n\n\n12\n\n\n\n\n\n\n\n1\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n,\n\n\n\n(\n\nx\n,\n\n\ny\n,\n\n\nz\n\n)\n\n=\n\n(\n\n2\n,\n\n\n\n4\n,\n\n\n\n4\n\n)\n\n+\nt\n\n(\n\n6\n,\n\n\n8\n,\n\n\n\n5\n\n)\n\n,\n \n=\n\n(\n\n\n\n\n\n4\n+\n6\nt\n\n\n\n\n\n12\n+\n8\nt\n\n\n\n\n\n\n\n1\n\n5\nt\n\n\n\n)\n\n

\n

Note: Award A1 for the form a + tb, A1 for the form L = a + tb, A0 for the form rb + ta.

\n

[2 marks]

\n
b.i.
\n
\n

METHOD 1 (solving for t)

\n

valid approach       (M1)

\n

eg   \n\n(\n\n\n\n\nk\n\n\n\n\n12\n\n\n\n\n\nk\n\n\n\n)\n\n=\n\n(\n\n\n\n\n\n2\n\n\n\n\n\n4\n\n\n\n\n\n4\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n,\n\n\n\n(\n\n\n\n\nk\n\n\n\n\n12\n\n\n\n\n\nk\n\n\n\n)\n\n=\n\n(\n\n\n\n\n\n4\n\n\n\n\n\n12\n\n\n\n\n\n\n\n1\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n

\n

one correct equation       A1

\n

eg −4 + 8t = 12, −12 + 8t = 12

\n

correct value for t       (A1)

\n

eg   t = 2 or 3

\n

correct substitution      A1

\n

eg  2 + 6(2), −4 + 6(3), −[1 + 3(−5)]

\n

k = 14      AG N0

\n

 

\n

METHOD 2 (solving simultaneously)

\n

valid approach      (M1)

\n

eg  \n\n(\n\n\n\n\nk\n\n\n\n\n12\n\n\n\n\n\nk\n\n\n\n)\n\n=\n\n(\n\n\n\n\n\n2\n\n\n\n\n\n4\n\n\n\n\n\n4\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n,\n\n\n\n(\n\n\n\n\nk\n\n\n\n\n12\n\n\n\n\n\nk\n\n\n\n)\n\n=\n\n(\n\n\n\n\n\n4\n\n\n\n\n\n12\n\n\n\n\n\n\n\n1\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n

\n

two correct equations in        A1

\n

eg   k = −4 + 6t, −k = 1 −5t

\n

EITHER (eliminating k)

\n

correct value for t       (A1)

\n

eg    t = 2 or 3

\n

correct substitution      A1

\n

eg  2 + 6(2), −4 + 6(3)

\n

OR (eliminating t)

\n

correct equation(s)      (A1)

\n

eg   5k + 20 = 30t and −6k − 6 = 30t, −k = 1 − 5\n\n(\n\n\n\nk\n+\n4\n\n6\n\n\n)\n\n

\n

correct working clearly leading to k = 14      A1

\n

eg  k + 14 = 0, −6k = 6 −5k − 20, 5k = −20 + 6(1 + k)

\n

THEN

\n

k = 14       AG N0

\n

[4 marks]

\n

 

\n
b.ii.
\n
\n

correct substitution into scalar product       A1

\n

eg   (2)(6) − (4)(8) − (4)(−5), 12 − 32 + 20

\n

\n\n\n\nOB\n\n\n\n\n\n\n\n\n\nAB\n\n\n\n\n = 0      A1 N0

\n

[2 marks]

\n

 

\n
c.i.
\n
\n

\n\nO\n\n\n\nB\n\n\n\n\n\nA\n\n=\n\nπ\n2\n\n,\n\n\n\n90\n\n\n\n\n\n\n\n\n(\n\n\naccept\n\n\n\n\n3\nπ\n\n2\n\n,\n\n\n\n270\n\n\n\n)\n\n\n      A1 N1

\n

[1 marks]

\n
c.ii.
\n
\n

METHOD 1 (\n\n1\n2\n\n × height × CD)

\n

recognizing that OB is altitude of triangle with base CD (seen anywhere)      M1

\n

eg   \n\n1\n2\n\n×\n\n|\n\n\n\n\nOB\n\n\n\n\n\n|\n\n×\n\n|\n\n\n\n\nCD\n\n\n\n\n\n|\n\n,\n\n\n\nOB\n\n\n\nCD\n\n,\n sketch showing right angle at B

\n

\n

\n\n\n\nCD\n\n\n\n\n=\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n or \n\n\n\nDC\n\n\n\n\n=\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n  (seen anywhere)       (A1)

\n

correct magnitudes (seen anywhere)      (A1)(A1)

\n

\n\n|\n\n\n\n\nOB\n\n\n\n\n\n|\n\n=\n\n\n\n\n\n(\n2\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n4\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n4\n\n)\n\n\n2\n\n\n\n=\n\n(\n\n\n36\n\n\n)\n\n

\n

\n\n|\n\n\n\n\nCD\n\n\n\n\n\n|\n\n=\n\n\n\n\n\n(\n\n\n6\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n8\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n5\n)\n\n\n2\n\n\n\n=\n\n(\n\n\n125\n\n\n)\n\n

\n

correct substitution into \n\n1\n2\n\nb\nh\n      A1

\n

eg     \n\n1\n2\n\n×\n6\n×\n\n125\n\n 

\n

area \n=\n3\n\n125\n\n,\n\n\n15\n\n5\n\n      A1 N3

\n

 

\n

METHOD 2 (subtracting triangles)

\n

recognizing that OB is altitude of either ΔOBD or ΔOBC(seen anywhere)       M1

\n

eg  \n\n1\n2\n\n×\n\n|\n\n\n\n\nOB\n\n\n\n\n\n|\n\n×\n\n|\n\n\n\n\nBD\n\n\n\n\n\n|\n\n,\n\n\n\nOB\n\n\n\nBC\n\n,\n sketch of triangle showing right angle at B

\n

\n

one correct vector \n\n\n\nBD\n\n\n\n\n or \n\n\n\nDB\n\n\n\n\n or \n\n\n\nBC\n\n\n\n\n or \n\n\n\nCB\n\n\n\n\n (seen anywhere)       (A1)

\n

eg   \n\n\n\nBD\n\n\n\n\n=\n\n(\n\n\n\n\n6\n\n\n\n\n\n8\n\n\n\n\n\n5\n\n\n\n)\n\n\n\n\n\nCB\n\n\n\n\n=\n\n(\n\n\n\n\n12\n\n\n\n\n\n16\n\n\n\n\n\n10\n\n\n\n)\n\n

\n

\n\n|\n\n\n\n\nOB\n\n\n\n\n\n|\n\n=\n\n\n\n\n\n(\n2\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n4\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n4\n\n)\n\n\n2\n\n\n\n=\n\n(\n\n\n36\n\n\n)\n\n (seen anywhere)       (A1)

\n

one correct magnitude of a base (seen anywhere)        (A1)

\n

\n\n|\n\n\n\n\nBD\n\n\n\n\n\n|\n\n=\n\n\n\n\n\n(\n6\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n8\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n5\n)\n\n\n2\n\n\n\n=\n\n(\n\n\n125\n\n\n)\n\n,\n\n\n\n|\n\n\n\n\nBC\n\n\n\n\n\n|\n\n=\n\n144\n+\n256\n+\n100\n\n=\n\n(\n\n\n500\n\n\n)\n\n

\n

correct working       A1

\n

eg  \n\n1\n2\n\n×\n6\n×\n\n500\n\n\n\n1\n2\n\n×\n6\n×\n5\n\n5\n\n,\n\n\n\n1\n2\n\n×\n6\n×\n\n500\n\n×\n\nsin\n\n90\n\n\n1\n2\n\n×\n6\n×\n5\n\n5\n\n×\n\nsin\n\n90\n

\n

area \n=\n3\n\n125\n\n,\n\n\n15\n\n5\n\n      A1 N3

\n

 

\n

METHOD 3 (using \n\n1\n2\n\nab sin C with ΔOCD)

\n

two correct side lengths (seen anywhere)      (A1)(A1)

\n

\n\n|\n\n\n\n\nOD\n\n\n\n\n\n|\n\n=\n\n\n\n\n\n(\n8\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n4\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n9\n\n)\n\n\n2\n\n\n\n=\n\n(\n\n\n161\n\n\n)\n\n,\n\n\n\n|\n\n\n\n\nCD\n\n\n\n\n\n|\n\n=\n\n\n\n\n\n(\n\n\n6\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n8\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n5\n)\n\n\n2\n\n\n\n=\n\n(\n\n\n125\n\n\n)\n\n,\n\n \n\n|\n\n\n\n\nOC\n\n\n\n\n\n|\n\n=\n\n\n\n\n\n(\n\n14\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n12\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n\n14\n\n)\n\n\n2\n\n\n\n=\n\n(\n\n\n536\n\n\n)\n\n

\n

attempt to find cosine ratio (seen anywhere)       M1
eg  \n\n\n536\n\n286\n\n\n\n2\n\n161\n\n\n125\n\n\n\n,\n\n\n\n\n\nOD\n\n\n\nDC\n\n\n\n\n|\n\nO\nD\n\n|\n\n\n|\n\nD\nC\n\n|\n\n\n\n

\n

correct working for sine ratio       A1

\n

eg   \n\n\n\n\n\n\n(\n\n125\n\n)\n\n\n2\n\n\n\n\n161\n×\n125\n\n\n+\n\nsi\n\n\n\n\nn\n\n2\n\n\n\nD\n=\n1\n

\n

correct substitution into \n\n1\n2\n\na\nb\n\n\n\nsin\n\n\nC\n       A1

\n

eg  \n0.5\n×\n\n161\n\n×\n\n125\n\n×\n\n6\n\n\n161\n\n\n\n

\n

area \n=\n3\n\n125\n\n,\n\n\n15\n\n5\n\n      A1 N3

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "18M.1.SL.TZ1.S_9", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

The vectors a = \n\n(\n\n\n\n\n4\n\n\n\n\n2\n\n\n\n\n)\n\n and b = \n\n(\n\n\n\n\n\nk\n+\n3\n\n\n\n\n\nk\n\n\n\n\n)\n\n are perpendicular to each other.

\n

 

\n
\n

Find the value of k .

\n
[4]
\n
a.
\n
\n

Given that c = a + 2b, find c.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of scalar product     M1

\n

eg a b, 4 ( k + 3 ) + 2 k

\n

recognizing scalar product must be zero     (M1)

\n

eg a b = 0 ,   4 k + 12 + 2 k = 0

\n

correct working (must involve combining terms)     (A1)

\n

eg   6 k + 12 , 6 k = 12

\n

k = 2     A1     N2

\n

[4 marks]

\n
a.
\n
\n

attempt to substitute their value of k (seen anywhere)     (M1)

\n

eg b = ( 2 + 3 2 ) , 2b = ( 2 4 )

\n

correct working     (A1)

\n

eg ( 4 2 ) + ( 2 4 ) ,   ( 4 + 2 k + 6 2 + 2 k )

\n

c = ( 6 2 )     A1     N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ2.S_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

Consider the function f defined by fx=90e-0.5x for x+.

\n

The graph of f and the line y=x intersect at point P.

\n
\n

The line L has a gradient of -1 and is a tangent to the graph of f at the point Q.

\n
\n

The shaded region A is enclosed by the graph of f and the lines y=x and L.

\n

\n
\n

Find the x-coordinate of P.

\n
[2]
\n
a.
\n
\n

Find the exact coordinates of Q.

\n
[4]
\n
b.
\n
\n

Show that the equation of L is y=-x+2ln45+2.

\n
[2]
\n
c.
\n
\n

Find the x-coordinate of the point where L intersects the line y=x.

\n
[1]
\n
d.i.
\n
\n

Hence, find the area of A.

\n
[4]
\n
d.ii.
\n
\n

The line L is tangent to the graphs of both f and the inverse function f-1.

\n

\n

Find the shaded area enclosed by the graphs of f and f-1 and the line L.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

Attempt to find the point of intersection of the graph of f and the line y=x         (M1)

\n

x=5.56619

\n

=5.57          A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

f'x=-45e-0.5x          A1

\n

attempt to set the gradient of f equal to -1         (M1)

\n

-45e-0.5x=-1

\n

Q has coordinates 2ln45, 2 (accept (-2ln145, 2)          A1A1

\n

 

\n

Note: Award A1 for each value, even if the answer is not given as a coordinate pair.

\n

   Do not accept ln145-0.5 or ln450.5 as a final value for x. Do not accept 2.0 or 2.00 as a final value for y.

\n

 

\n

[4 marks]

\n
b.
\n
\n

attempt to substitute coordinates of Q (in any order) into an appropriate equation         (M1)

\n

y-2=-x-2ln45  OR  2=-2ln45+c          A1

\n

equation of L is y=-x+2ln45+2           AG

\n

 

\n

[2 marks]

\n
c.
\n
\n

x=ln45+1=4.81          A1

\n

 

\n

[1 mark]

\n
d.i.
\n
\n

appropriate method to find the sum of two areas using integrals of the difference of two functions          (M1)

\n

 

\n

Note: Allow absence of incorrect limits.

\n

 

\n

4.8065.566x--x+2ln45+2dx+5.5667.61390e-0.5x--x+2ln45+2dx        (A1)(A1)

\n

 

\n

Note: Award A1 for one correct integral expression including correct limits and integrand.
          Award A1 for a second correct integral expression including correct limits and integrand.

\n

 

\n

=1.52196

\n

=1.52        A1

\n

 

\n

[4 marks]

\n
d.ii.
\n
\n

by symmetry 2×1.52         (M1)

\n

=3.04         A1

\n

 

\n

Note: Accept any answer that rounds to 3.0 (but do not accept 3).

\n

  

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.2.SL.TZ1.9", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-4-tangents-and-normal", "sl-5-5-integration-introduction-areas-between-curve-and-x-axis", "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

A group of 7 adult men wanted to see if there was a relationship between their Body Mass Index (BMI) and their waist size. Their waist sizes, in centimetres, were recorded and their BMI calculated. The following table shows the results.

\n

\n

The relationship between \nx\n and \ny\n can be modelled by the regression equation \ny\n=\na\nx\n+\nb\n.

\n
\n

Write down the value of \na\n and of \nb\n.

\n
[3]
\n
a.i.
\n
\n

Find the correlation coefficient.

\n
[1]
\n
a.ii.
\n
\n

Use the regression equation to estimate the BMI of an adult man whose waist size is 95 cm.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid approach       (M1)

\n

eg      correct value for \na\n or \nb\n (or for correct \nr\n or \n\n\nr\n2\n\n\n = 0.955631 seen in (ii))

\n

0.141120,  11.1424

\n

\na\n = 0.141,  \nb\n = 11.1     A1A1 N3

\n

[3 marks]

\n
a.i.
\n
\n

0.977563

\n

\nr\n = 0.978     A1 N1

\n

[1 mark]

\n
a.ii.
\n
\n

correct substitution into their regression equation       (A1)

\n

eg      0.141(95) + 11.1

\n

24.5488

\n

24.5       A1 N2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.SL.TZ2.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A bag contains 5 green balls and 3 white balls. Two balls are selected at random without replacement.

\n
\n

Complete the following tree diagram.

\n

\"N17/5/MATME/SP1/ENG/TZ0/01.a\"

\n
[3]
\n
a.
\n
\n

Find the probability that exactly one of the selected balls is green.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct probabilities

\n

\"N17/5/MATME/SP1/ENG/TZ0/01.a/M\"     A1A1A1     N3

\n

 

\n

Note:     Award A1 for each correct bold answer.

\n

 

\n

[3 marks]

\n
a.
\n
\n

multiplying along branches     (M1)

\n

eg 5 8 × 3 7 ,   3 8 × 5 7 ,   15 56

\n

adding probabilities of correct mutually exclusive paths     (A1)

\n

eg 5 8 × 3 7 + 3 8 × 5 7 ,   15 56 + 15 56

\n

30 56   ( = 15 28 )     A1     N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.SL.TZ0.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The histogram shows the time, t, in minutes, that it takes the customers of a restaurant to eat their lunch on one particular day. Each customer took less than 25 minutes.

\n

The histogram is incomplete, and only shows data for 0 ≤ t < 20.

\n

\n
\n

The mean time it took all customers to eat their lunch was estimated to be 12 minutes.

\n

It was found that k customers took between 20 and 25 minutes to eat their lunch.

\n
\n

Write down the mid-interval value for 10 ≤ t < 15.

\n
[1]
\n
a.
\n
\n

Write down the total number of customers in terms of k.

\n
[1]
\n
b.i.
\n
\n

Calculate the value of k.

\n
[3]
\n
b.ii.
\n
\n

Hence, complete the histogram.

\n
[1]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

12.5     (A1) (C1)

\n

[1 mark]

\n
a.
\n
\n

33 + k  OR  10 + 8 + 5 + 10 + k     (A1)

\n

Note: Award (A1) for “number of customers = 33 + k”.

\n

[1 mark]

\n
b.i.
\n
\n

\n\n\n2.5\n×\n10\n+\n7.5\n×\n8\n+\n\n+\n22.5\n×\nk\n\n\n33\n+\nk\n\n\n=\n12\n     (M1)(A1)(ft)

\n

Note: Award (M1) for substitution into the mean formula and equating to 12, (A1)(ft) for their correct substitutions.

\n

(k =) 7     (A1)(ft) (C4)

\n

Note: Follow through from part (b)(i) and their mid-interval values, consistent with part (a). Do not award final (A1) if answer is not an integer.

\n

[3 marks]

\n
b.ii.
\n
\n

(A1)(ft) (C1)

\n

Note: Follow through from their part (b)(ii) but only if the value is between 1 and 10, inclusive.

\n

[1 mark]

\n

 

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ2.T_12", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

A line \n\n\nL\n1\n\n\n passes through the points \n\nA\n\n(\n0\n,\n\n \n\n1\n,\n\n \n\n8\n)\n and \n\nB\n\n(\n3\n,\n\n \n\n5\n,\n\n \n\n2\n)\n.

\n
\n

Given that \n\n\nL\n1\n\n\n and \n\n\nL\n2\n\n\n are perpendicular, show that \np\n=\n2\n.

\n
\n

Find \n\n\nA\nB\n\n\n\n.

\n
[2]
\n
a.i.
\n
\n

Hence, write down a vector equation for \n\n\nL\n1\n\n\n.

\n
[2]
\n
a.ii.
\n
\n

A second line \n\n\nL\n2\n\n\n, has equation r = \n\n(\n\n\n\n\n1\n\n\n\n\n\n13\n\n\n\n\n\n\n\n14\n\n\n\n\n\n)\n\n+\ns\n\n(\n\n\n\n\np\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n.

\n

Given that \n\n\nL\n1\n\n\n and \n\n\nL\n2\n\n\n are perpendicular, show that \np\n=\n2\n.

\n
[3]
\n
b.
\n
\n

The lines \n\n\nL\n1\n\n\n and \n\n\nL\n1\n\n\n intersect at \nC\n(\n9\n,\n\n \n\n13\n,\n\n \n\nz\n)\n. Find \nz\n.

\n
[5]
\n
c.
\n
\n

Find a unit vector in the direction of \n\n\nL\n2\n\n\n.

\n
[2]
\n
d.i.
\n
\n

Hence or otherwise, find one point on \n\n\nL\n2\n\n\n which is \n\n5\n\n units from C.

\n
[3]
\n
d.ii.
\n
", "Markscheme": "
\n

valid approach     (M1)

\n

eg  \nA\n\nB\n,\n\n\n\n\n(\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n8\n\n\n\n)\n\n+\n\n(\n\n\n\n3\n\n\n\n\n5\n\n\n\n\n2\n\n\n\n)\n\n

\n

\n\n\nA\nB\n\n\n\n=\n\n(\n\n\n\n3\n\n\n\n\n4\n\n\n\n\n\n6\n\n\n\n)\n\n    A1     N2

\n

[2 marks]

\n
a.i.
\n
\n

any correct equation in the form r = a + tb (any parameter for \nt\n)     A2     N2

\n

where a is \n\n(\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n8\n\n\n\n)\n\n or \n\n(\n\n\n\n3\n\n\n\n\n5\n\n\n\n\n2\n\n\n\n)\n\n, and is a scalar multiple of \n\n(\n\n\n\n3\n\n\n\n\n4\n\n\n\n\n\n6\n\n\n\n)\n\n

\n

 

\n

eg\n\n\n\n\n\nr = \n\n(\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n8\n\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n3\n\n\n\n\n4\n\n\n\n\n\n\n6\n\n\n\n\n\n)\n\n, r = \n\n(\n\n\n\n\n\n3\n+\n3\nt\n\n\n\n\n\n\n5\n+\n4\nt\n\n\n\n\n\n\n2\n\n6\nt\n\n\n\n\n\n)\n\n, r = j + 8k + t(3i + 4j – 6k)

\n

 

\n

Note:     Award A1 for the form a + tb, A1 for the form L = a + tb, A0 for the form r = b + ta.

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\na\n\nb\n=\n0\n

\n

choosing correct direction vectors (may be seen in scalar product)     A1

\n

eg\n\n\n\n\n\n\n\n(\n\n\n\n\n3\n\n\n\n\n4\n\n\n\n\n\n\n6\n\n\n\n\n\n)\n\n and \n\n(\n\n\n\n\np\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n,\n\n \n\n\n(\n\n\n\n\n3\n\n\n\n\n4\n\n\n\n\n\n\n6\n\n\n\n\n\n)\n\n\n\n(\n\n\n\n\np\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n=\n0\n

\n

correct working/equation     A1

\n

eg\n\n\n\n\n\n\n3\np\n\n6\n=\n0\n

\n

\np\n=\n2\n     AG     N0

\n

[3 marks]

\n
b.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\n\nL\n1\n\n\n=\n\n(\n\n\n\n\n9\n\n\n\n\n\n13\n\n\n\n\n\nz\n\n\n\n\n)\n\n,\n\n \n\n\n\nL\n1\n\n\n=\n\n\nL\n2\n\n\n

\n

one correct equation (must be different parameters if both lines used)     (A1)

\n

eg\n\n\n\n\n\n\n3\nt\n=\n9\n,\n\n \n\n1\n+\n2\ns\n=\n9\n,\n\n \n\n5\n+\n4\nt\n=\n13\n,\n\n \n\n3\nt\n=\n1\n+\n2\ns\n

\n

one correct value     A1

\n

eg\n\n\n\n\n\n\nt\n=\n3\n,\n\n \n\ns\n=\n4\n,\n\n \n\nt\n=\n2\n

\n

valid approach to substitute their \nt\n or \ns\n value     (M1)

\n

eg\n\n\n\n\n\n\n8\n+\n3\n(\n\n6\n)\n,\n\n \n\n\n14\n+\n4\n(\n1\n)\n

\n

\nz\n=\n\n10\n     A1     N3

\n

[5 marks]

\n
c.
\n
\n

\n\n|\n\n\n\nd\n\n\n\n\n|\n\n=\n\n\n\n2\n2\n\n\n+\n1\n\n\n\n\n(\n\n=\n\n5\n\n\n)\n\n    (A1)

\n

\n\n1\n\n\n5\n\n\n\n\n(\n\n\n\n\n2\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n\n\n\n\n\n\n(\n\n\naccept\n\n\n(\n\n\n\n\n\n\n2\n\n\n5\n\n\n\n\n\n\n\n\n\n\n0\n\n\n5\n\n\n\n\n\n\n\n\n\n\n1\n\n\n5\n\n\n\n\n\n\n\n\n)\n\n\n)\n\n     A1     N2

\n

[2 marks]

\n
d.i.
\n
\n

METHOD 1 (using unit vector) 

\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\n(\n\n\n\n\n9\n\n\n\n\n\n13\n\n\n\n\n\n\n\n10\n\n\n\n\n\n)\n\n±\n\n5\n\n\n\nd\n^\n\n\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n\n(\n\n\n\n\n9\n\n\n\n\n\n13\n\n\n\n\n\n\n\n10\n\n\n\n\n\n)\n\n+\n\n(\n\n\n\n\n2\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n,\n\n \n\n\n(\n\n\n\n\n9\n\n\n\n\n\n13\n\n\n\n\n\n\n\n10\n\n\n\n\n\n)\n\n\n\n(\n\n\n\n\n2\n\n\n\n\n0\n\n\n\n\n1\n\n\n\n\n)\n\n

\n

one correct point     A1     N2

\n

eg\n\n\n\n\n\n\n(\n11\n,\n\n \n\n13\n,\n\n \n\n\n9\n)\n,\n\n \n\n(\n7\n,\n\n \n\n13\n,\n\n \n\n\n11\n)\n

\n

METHOD 2 (distance between points) 

\n

attempt to use distance between \n(\n1\n+\n2\ns\n,\n\n \n\n13\n,\n\n \n\n\n14\n+\ns\n)\n and \n(\n9\n,\n\n \n\n13\n,\n\n \n\n\n10\n)\n     (M1)

\n

eg\n\n\n\n\n\n\n\n(\n2\ns\n\n8\n\n)\n2\n\n\n+\n\n\n0\n2\n\n\n+\n\n(\ns\n\n4\n\n)\n2\n\n\n=\n5\n

\n

solving \n5\n\n\ns\n2\n\n\n\n40\ns\n+\n75\n=\n0\n leading to \ns\n=\n5\n or \ns\n=\n3\n     (A1)

\n

one correct point     A1     N2

\n

eg\n\n\n\n\n\n\n(\n11\n,\n\n \n\n13\n,\n\n \n\n\n9\n)\n,\n\n \n\n(\n7\n,\n\n \n\n13\n,\n\n \n\n\n11\n)\n

\n

[3 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "17M.1.SL.TZ1.S_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

Consider the planes Π1 and Π2 with the following equations.

\n

Π13x+2y+z=6

\n

Π2x-2y+z=4

\n
\n

Find a Cartesian equation of the plane Π3 which is perpendicular to Π1 and Π2 and passes through the origin (0, 0, 0).

\n
[3]
\n
a.
\n
\n

Find the coordinates of the point where Π1, Π2 and Π3 intersect.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

attempt to find a vector perpendicular to Π1 and Π2 using a cross product        (M1)

\n

321×1-21=2--2i+1-3j+-6-2k

\n

=4-2-8=22-1-4        (A1)

\n

equation is 4x-2y-8z=02x-y-4z=0        A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

attempt to solve 3 simultaneous equations in 3 variables       (M1)

\n

4121,-1021,2321=1.95,-0.476,1.10        A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.AHL.TZ1.6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-16-vector-product" ] }, { "Question": "
\n

A continuous random variable X has the probability density function f given by

\n

fx=xx2+k3        0x4      0                 otherwise

\n

where k+.

\n
\n

Show that 16+k-k=k16+k.

\n
[5]
\n
a.
\n
\n

Find the value of k.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

recognition of the need to integrate xx2+k3       (M1)

\n

xx2+k3dx=1

\n

 

\n

EITHER

\n

u=x2+kdudx=2x (or equivalent)       (A1)

\n

xx2+k3dx=12u-32du

\n

=-u-12+c=-x2+k-12+c        A1

\n

 

\n

OR

\n

xx2+k3dx=122xx2+k3dx       (A1)

\n

=-x2+k-12+c        A1

\n

 

\n

THEN

\n

attempt to use correct limits for their integrand and set equal to 1        M1

\n

-u-12k16+k=1  OR  -x2+k-1204=1

\n

-16+k-12+k-12=11k-116+k=1        A1

\n

16+k-k=k16+k        AG

\n

 

\n

[5 marks]

\n
a.
\n
\n

attempt to solve 16+k-k=k16+k      (M1)

\n

k=0.645038

\n

=0.645        A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.AHL.TZ1.7", "topics": [ "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution", "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

Consider the complex numbers z=2cosπ5+isinπ5 and w=8cos2kπ5-isin2kπ5, where k+.

\n
\n

Suppose that zw.

\n
\n

Find the modulus of zw.

\n
[1]
\n
a.
\n
\n

Find the argument of zw in terms of k.

\n
[2]
\n
b.
\n
\n

Find the minimum value of k.

\n
[3]
\n
c.i.
\n
\n

For the value of k found in part (i), find the value of zw.

\n
[1]
\n
c.ii.
\n
", "Markscheme": "
\n

zw=16     A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

attempt to find argz+argw       (M1)

\n

argzw=argz+argw

\n

=π5-2kπ5=1-2kπ5       A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

zwargzw is a multiple of π       (M1)

\n

1-2k is a multiple of 5       (M1)

\n

k=3       A1

\n

 

\n

[3 marks]

\n
c.i.
\n
\n

zw=16cos-π+isin-π

\n

-16         A1

\n

 

\n

[1 mark]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "21M.2.AHL.TZ1.8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-13-polar-and-euler-form" ] }, { "Question": "
\n

A line, \n\n\nL\n1\n\n\n, has equation \nr\n=\n\n(\n\n\n\n\n\n\n3\n\n\n\n\n\n9\n\n\n\n\n\n10\n\n\n\n\n\n)\n\n+\ns\n\n(\n\n\n\n\n6\n\n\n\n\n0\n\n\n\n\n2\n\n\n\n\n)\n\n. Point \n\nP\n\n\n(\n\n15\n\n,\n\n\n\n9\n\n,\n\n\n\nc\n\n)\n\n lies on \n\n\nL\n1\n\n\n.

\n
\n

Find c .

\n
[4]
\n
a.
\n
\n

A second line, L 2 , is parallel to L 1 and passes through (1, 2, 3).

\n

Write down a vector equation for  L 2 .

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

correct equation       (A1)

\n

eg      3 + 6 s = 15 ,   6 s = 18

\n

s = 3              (A1)

\n

substitute their s value into z component             (M1)

\n

eg    10 + 3 ( 2 ) 10 + 6

\n

c = 16      A1 N3

\n

[4 marks]

\n
a.
\n
\n

r = ( 1 2 3 ) + t ( 6 0 2 ) (=(i + 2j + 3k) + t (6i + 2k))     A2 N2

\n

Note: Accept any scalar multiple of  ( 6 0 2 ) for the direction vector.

\n

Award A1 for  ( 1 2 3 ) + t ( 6 0 2 ) , A1 for  L 2 = ( 1 2 3 ) + t ( 6 0 2 ) A0 for r = ( 6 0 2 ) + t ( 1 2 3 ) .

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.SL.TZ1.S_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-14-vector-equation-of-line" ] }, { "Question": "
\n

Two boats A and B travel due north.

\n

Initially, boat B is positioned 50 metres due east of boat A.

\n

The distances travelled by boat A and boat B, after t seconds, are x metres and y metres respectively. The angle θ is the radian measure of the bearing of boat B from boat A. This information is shown on the following diagram.

\n

\n
\n

Show that y=x+50cotθ .

\n
[1]
\n
a.
\n
\n

At time T, the following conditions are true.

\n

Boat B has travelled 10 metres further than boat A.
Boat B is travelling at double the speed of boat A.
The rate of change of the angle θ is -0.1 radians per second.

\n

Find the speed of boat A at time T.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

tanθ=50y-x  OR  cotθ=y-x50        A1

\n

y=x+50cotθ        AG

\n

 

\n

Note: y-x may be identified as a length on a diagram, and not written explicitly.

\n

 

\n

[1 mark]

\n
a.
\n
\n

attempt to differentiate with respect to t         (M1)

\n

dydt=dxdt-50cosecθ2dθdt        A1

\n

attempt to set speed of B equal to double the speed of A        (M1)

\n

2dxdt=dxdt-50cosecθ2dθdt

\n

dxdt=-50cosecθ2dθdt        A1

\n

θ=arctan5=1.373=78.69°  OR  cosec2θ=1+cot2θ=1+152=2625        (A1)

\n

 

\n

Note: This A1 can be awarded independently of previous marks.

\n

 

\n

dxdt=-502625×-0.1

\n

So the speed of boat A is 5.2ms-1        A1

\n

 

\n

Note: Accept 5.20 from the use of inexact values.

\n

 

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.AHL.TZ1.9", "topics": [ "topic-3-geometry-and-trigonometry", "topic-5-calculus" ], "subtopics": [ "ahl-3-9-reciprocal-trig-ratios-and-their-pythagorean-identities-inverse-circular-functions", "ahl-5-14-implicit-functions-related-rates-optimisation" ] }, { "Question": "
\n

Consider the vectors a\n\n(\n\n\n\n\n0\n\n\n\n\n3\n\n\n\n\np\n\n\n\n\n)\n\n and b = \n\n(\n\n\n\n\n0\n\n\n\n\n6\n\n\n\n\n\n18\n\n\n\n\n\n)\n\n.

\n

Find the value of \np\n for which a and b are

\n
\n

parallel.

\n
[2]
\n
a.
\n
\n

perpendicular.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach       (M1)

\n

eg     b = 2a,  a = \nk\nb,  cos θ = 1,  ab = −|a||b|,  2\np\n = 18

\n

\np\n = 9       A1 N2

\n

[2 marks]

\n
a.
\n
\n

evidence of scalar product      (M1)

\n

eg    ab,  (0)(0) + (3)(6) + \np\n(18)

\n

recognizing ab = 0 (seen anywhere)       (M1)

\n

correct working (A1)

\n

eg   18 + 18\np\n = 0,   18\np\n = −18       (A1)

\n

\np\n = −1       A1 N3

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.SL.TZ2.S_2", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions" ] }, { "Question": "
\n

The vector equation of line \nL\n is given by r \n=\n\n(\n\n\n\n\n\n\n1\n\n\n\n\n\n3\n\n\n\n\n8\n\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n4\n\n\n\n\n5\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n.

\n

Point P is the point on \nL\n that is closest to the origin. Find the coordinates of P.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 (Distance between the origin and P)

\n

correct position vector for OP       (A1)

\n

eg  \n\n\nOP\n\n\n\n=\n\n(\n\n\n\n\n\n\n1\n+\n4\nt\n\n\n\n\n\n\n3\n+\n5\nt\n\n\n\n\n\n\n8\n\nt\n\n\n\n\n\n)\n\n\n\nP\n\n=\n\n(\n\n\n1\n+\n4\nt\n\n,\n\n\n\n3\n+\n5\nt\n\n,\n\n\n\n8\n\nt\n\n)\n\n

\n

correct expression for OP or OP2 (seen anywhere)       A1

\n

eg   \n\n\n\n\n\n(\n\n\n1\n+\n4\nt\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n3\n+\n5\nt\n\n)\n\n\n2\n\n\n+\n\n\n\n\n(\n\n8\n\nt\n\n)\n\n\n2\n\n\n\n\n\n\n\n(\n\n\n1\n+\n4\nx\n\n)\n\n2\n\n\n+\n\n\n\n(\n\n3\n+\n5\nx\n\n)\n\n2\n\n\n+\n\n\n\n(\n\n8\n\nx\n\n)\n\n2\n\n\n

\n

valid attempt to find the minimum of OP       (M1)

\n

eg   \n\nd\n\n\n=\n0\n, root on sketch of \n\nd\n\n\n,  min indicated on sketch of \nd\n

\n

\nt\n=\n\n\n1\n\n14\n\n\n\n,\n\n\n\n\n0.0714285\n      (A1)

\n

substitute their value of \nt\n into \nL\n (only award if there is working to find \nt\n)       (M1)

\n

eg   one correct coordinate,  \n\n1\n+\n4\n\n(\n\n\n\n1\n\n14\n\n\n\n)\n\n

\n

\n\n(\n\n\n1.28571\n\n,\n\n\n\n2.64285\n\n,\n\n\n\n8.07142\n\n)\n\n

\n

\n\n(\n\n\n\n9\n7\n\n\n,\n\n\n\n\n\n37\n\n\n14\n\n\n\n,\n\n\n\n\n\n113\n\n\n14\n\n\n\n)\n\n\n\n\n=\n\n(\n\n\n1.29\n\n,\n\n\n\n2.64\n\n,\n\n\n\n8.07\n\n)\n\n       A1  N2

\n

 

\n

METHOD 2 (Perpendicular vectors)

\n

recognizing that closest implies perpendicular     (M1)

\n

eg  \n\n\nOP\n\n\n\n\n\nL\n  (may be seen on sketch), \na\n\nb\n=\n0\n

\n

valid approach involving \n\n\nOP\n\n\n\n       (M1)

\n

eg   \n\n\nOP\n\n\n\n=\n\n(\n\n\n\n\n\n\n1\n+\n4\nt\n\n\n\n\n\n\n3\n+\n5\nt\n\n\n\n\n\n\n8\n\nt\n\n\n\n\n\n)\n\n\n,\n\n\n\n\n(\n\n\n\n\n4\n\n\n\n\n5\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n\n\n\nOP\n\n\n\n\n,\n\n\n\n\n(\n\n\n\n\n4\n\n\n\n\n5\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n\n\n\nOP\n\n\n\n

\n

correct scalar product        A1

\n

eg   \n4\n\n(\n\n\n1\n+\n4\nt\n\n)\n\n+\n5\n\n(\n\n3\n+\n5\nt\n\n)\n\n\n1\n\n(\n\n8\n\nt\n\n)\n\n ,  \n\n4\n+\n16\nt\n+\n15\n+\n25\nt\n\n8\n+\nt\n=\n0\n,  \n42\nt\n+\n3\n

\n

\nt\n=\n\n\n1\n\n14\n\n\n\n,\n\n\n\n\n0.0714285\n      (A1)

\n

substitute their value of \nt\n into \nL\n or \n\n\nOP\n\n\n\n (only award if scalar product used to find \nt\n)      (M1)

\n

eg   one correct coordinate,  \n\n1\n+\n4\n\n(\n\n\n\n1\n\n14\n\n\n\n)\n\n

\n

\n\n(\n\n\n1.28571\n\n,\n\n\n\n2.64285\n\n,\n\n\n\n8.07142\n\n)\n\n

\n

\n\n(\n\n\n\n9\n7\n\n\n,\n\n\n\n\n\n37\n\n\n14\n\n\n\n,\n\n\n\n\n\n113\n\n\n14\n\n\n\n)\n\n\n\n\n=\n\n(\n\n\n1.29\n\n,\n\n\n\n2.64\n\n,\n\n\n\n8.07\n\n)\n\n       A1  N2

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.2.SL.TZ2.S_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

Let \n\n\n\nOA\n\n\n\n\n=\n\n(\n\n\n\n2\n\n\n\n\n1\n\n\n\n\n3\n\n\n\n)\n\n and \n\n\n\nAB\n\n\n\n\n=\n\n(\n\n\n\n1\n\n\n\n\n3\n\n\n\n\n1\n\n\n\n)\n\n, where O is the origin. L1 is the line that passes through A and B.

\n
\n

Find a vector equation for L1.

\n
[2]
\n
a.
\n
\n

The vector \n\n(\n\n\n\n2\n\n\n\n\np\n\n\n\n\n0\n\n\n\n)\n\n is perpendicular to \n\n\n\nAB\n\n\n\n\n. Find the value of p.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

any correct equation in the form r = a + tb (accept any parameter for t)

\n

where a is \n\n(\n\n\n\n2\n\n\n\n\n1\n\n\n\n\n3\n\n\n\n)\n\n, and b is a scalar multiple of \n\n(\n\n\n\n1\n\n\n\n\n3\n\n\n\n\n1\n\n\n\n)\n\n     A2 N2

\n

eg r = \n\n(\n\n\n\n2\n\n\n\n\n1\n\n\n\n\n3\n\n\n\n)\n\n=\nt\n\n(\n\n\n\n1\n\n\n\n\n3\n\n\n\n\n1\n\n\n\n)\n\nr = 2i + j + 3k + s(i + 3j + k)

\n

Note: Award A1 for the form a + tb, A1 for the form L = a + tb, A0 for the form r = b + ta.

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

correct scalar product     (A1)

\n

eg  (1 × 2) + (3 × p) + (1 × 0), 2 + 3p

\n

evidence of equating their scalar product to zero     (M1)

\n

eg  a•b = 0, 2 + 3p = 0, 3p = −2

\n

\np\n=\n\n\n2\n3\n\n       A1 N3

\n

 

\n

METHOD 2

\n

valid attempt to find angle between vectors      (M1)

\n

correct substitution into numerator and/or angle       (A1)

\n

eg  \n\ncos\n\n\nθ\n=\n\n\n\n(\n\n1\n×\n2\n\n)\n\n+\n\n(\n\n3\n×\np\n\n)\n\n+\n\n(\n\n1\n×\n0\n\n)\n\n\n\n\n|\na\n|\n\n\n|\nb\n|\n\n\n\n,\n\n\n\ncos\n\n\nθ\n=\n0\n

\n

\np\n=\n\n\n2\n3\n\n       A1 N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ2.S_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The position vectors of points P and Q are i \n+\n 2 j \n\n k and 7i \n+\n 3j \n\n 4k respectively.

\n
\n

Find a vector equation of the line that passes through P and Q.

\n
[4]
\n
a.
\n
\n

The line through P and Q is perpendicular to the vector 2i \n+\n nk. Find the value of \nn\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid attempt to find direction vector     (M1)

\n

eg\n\n\n\n\n\n\n\n\nPQ\n\n\n\n,\n\n \n\n\n\nQP\n\n\n\n

\n

correct direction vector (or multiple of)     (A1)

\n

eg\n\n\n\n\n\n6i \n+\n j \n\n 3k

\n

any correct equation in the form r \n=\n a \n+\n tb (any parameter for \nt\n)     A2     N3

\n

where a is i \n+\n 2j \n\n k or 7i \n+\n 3j \n\n 4k , and b is a scalar multiple of 6i \n+\n j \n\n 3k

\n

eg\n\n\n\n\n\nr \n=\n 7i \n+\n 3j \n\n 4k \n+\n t(6i \n+\n j \n\n 3k), r \n=\n\n(\n\n\n\n\n\n1\n+\n6\ns\n\n\n\n\n\n\n2\n+\n1\ns\n\n\n\n\n\n\n\n1\n\n3\ns\n\n\n\n\n\n)\n\n,\n\n \n\nr\n=\n\n(\n\n\n\n\n1\n\n\n\n\n2\n\n\n\n\n\n\n1\n\n\n\n\n\n)\n\n+\nt\n\n(\n\n\n\n\n\n\n6\n\n\n\n\n\n\n\n1\n\n\n\n\n\n3\n\n\n\n\n)\n\n

\n

 

\n

Notes: Award A1 for the form a \n+\n tb, A1 for the form L \n=\n a \n+\n tb, A0 for the form r \n=\n b \n+\n ta.

\n

 

\n

[4 marks]

\n
a.
\n
\n

correct expression for scalar product     (A1)

\n

eg\n\n\n\n\n\n\n6\n×\n2\n+\n1\n×\n0\n+\n(\n\n3\n)\n×\nn\n,\n\n \n\n\n3\nn\n+\n12\n

\n

setting scalar product equal to zero (seen anywhere)     (M1)

\n

eg\n\n\n\n\n\nu \n\n v \n=\n0\n,\n\n \n\n\n3\nn\n+\n12\n=\n0\n

\n

\nn\n=\n4\n    A1     N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.S_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The following box-and-whisker plot shows the number of text messages sent by students in a school on a particular day.

\n

\n
\n

Find the value of the interquartile range.

\n
[2]
\n
a.
\n
\n

One student sent k text messages, where k > 11 . Given that k is an outlier, find the least value of k.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognizing Q1 or Q3 (seen anywhere)     (M1)

\n

eg    4,11 , indicated on diagram

\n

IQR = 7     A1 N2

\n

[2 marks]

\n
a.
\n
\n

recognizing the need to find 1.5 IQR     (M1)

\n

eg   1.5 × IQR, 1.5 × 7

\n

valid approach to find    (M1)

\n

eg   10.5 + 11, 1.5 × IQR + Q3

\n

21.5     (A1)

\n

k = 22     A1 N3

\n

Note: If no working shown, award N2 for an answer of 21.5.

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.1.SL.TZ1.S_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

Consider the following frequency table.

\n

\"M17/5/MATME/SP2/ENG/TZ1/01\"

\n
\n

Write down the mode.

\n
[1]
\n
a.i.
\n
\n

Find the value of the range.

\n
[2]
\n
a.ii.
\n
\n

Find the mean.

\n
[2]
\n
b.i.
\n
\n

Find the variance.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

\n\nmode\n\n=\n10\n     A1     N1

\n

[1 mark]

\n
a.i.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\n\nx\n\nmax\n\n\n\n\n\n\nx\n\nmin\n\n\n\n, interval 2 to 11

\n

\n\nrange\n\n=\n9\n          A1     N2

\n

[2 marks]

\n
a.ii.
\n
\n

7.14666

\n

\n\nmean\n\n=\n7.15\n     A2     N2

\n

[2 marks]

\n
b.i.
\n
\n

recognizing that variance is \n\n(\n\nsd\n\n\n)\n2\n\n\n     (M1)

\n

eg\n\n\n\n\n\n\nvar\n=\n\n\nσ\n2\n\n\n,\n\n 2.9060\n\n\n\n\n5\n\n2\n\n\n,\n\n \n\n\n\n2.92562\n2\n\n\n

\n

\n\n\nσ\n2\n\n\n=\n8.44515\n

\n

\n\n\nσ\n2\n\n\n=\n8.45\n     A1     N2

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "17M.2.SL.TZ1.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

A group of 800 students answered 40 questions on a category of their choice out of History, Science and Literature.

\n

For each student the category and the number of correct answers, \nN\n, was recorded. The results obtained are represented in the following table.

\n

\"N17/5/MATSD/SP2/ENG/TZ0/01\"

\n
\n

A \n\n\nχ\n2\n\n\n test at the 5% significance level is carried out on the results. The critical value for this test is 12.592.

\n
\n

State whether \nN\n is a discrete or a continuous variable.

\n
[1]
\n
a.
\n
\n

Write down, for \nN\n, the modal class;

\n
[1]
\n
b.i.
\n
\n

Write down, for \nN\n, the mid-interval value of the modal class.

\n
[1]
\n
b.ii.
\n
\n

Use your graphic display calculator to estimate the mean of \nN\n;

\n
[2]
\n
c.i.
\n
\n

Use your graphic display calculator to estimate the standard deviation of \nN\n.

\n
[1]
\n
c.ii.
\n
\n

Find the expected frequency of students choosing the Science category and obtaining 31 to 40 correct answers.

\n
[2]
\n
d.
\n
\n

Write down the null hypothesis for this test;

\n
[1]
\n
e.i.
\n
\n

Write down the number of degrees of freedom.

\n
[1]
\n
e.ii.
\n
\n

Write down the \np\n-value for the test;

\n
[1]
\n
f.i.
\n
\n

Write down the \n\n\nχ\n2\n\n\n statistic.

\n
[2]
\n
f.ii.
\n
\n

State the result of the test. Give a reason for your answer.

\n
[2]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

discrete     (A1)

\n

[1 mark]

\n
a.
\n
\n

\n11\n\nN\n\n20\n     (A1)

\n

[1 mark]

\n
b.i.
\n
\n

15.5     (A1)(ft)

\n

 

\n

Note:     Follow through from part (b)(i).

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

\n21.2\n\n \n\n(\n21.2125\n)\n     (G2)

\n

[2 marks]

\n
c.i.
\n
\n

\n9.60\n\n \n\n(\n9.60428\n\n)\n     (G1)

\n

[1 marks]

\n
c.ii.
\n
\n

\n\n\n260\n\n\n800\n\n\n×\n\n\n157\n\n\n800\n\n\n×\n800\n\n\n\n\nOR\n\n\n\n\n\n\n260\n×\n157\n\n\n800\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into expected frequency formula.

\n

 

\n

\n=\n51.0\n\n \n\n(\n51.025\n)\n     (A1)(G2)

\n

[2 marks]

\n
d.
\n
\n

choice of category and number of correct answers are independent     (A1)

\n

 

\n

Notes:     Accept “no association” between (choice of) category and number of correct answers. Do not accept “not related” or “not correlated” or “influenced”.

\n

 

\n

[1 mark]

\n
e.i.
\n
\n

6     (A1)

\n

[1 mark]

\n

 

\n
e.ii.
\n
\n

\n0.0644\n\n \n\n(\n0.0644123\n\n)\n     (G1)

\n

[1 mark]

\n
f.i.
\n
\n

\n11.9\n\n \n\n(\n11.8924\n\n)\n     (G2)

\n

[2 marks]

\n
f.ii.
\n
\n

the null hypothesis is not rejected (the null hypothesis is accepted)     (A1)(ft)

\n

OR

\n

(choice of) category and number of correct answers are independent     (A1)(ft)

\n

as \n11.9\n<\n12.592\n\n\n\n\nOR\n\n\n\n\n0.0644\n>\n0.05\n     (R1)

\n

 

\n

Notes:     Award (R1) for a correct comparison of either their \n\n\nχ\n2\n\n\n statistic to the \n\n\nχ\n2\n\n\n critical value or their \np\n-value to the significance level. Award (A1)(ft) from that comparison.

\n

Follow through from part (f). Do not award (A1)(ft)(R0).

\n

 

\n

[2 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
\n[N/A]\n
g.
\n
", "question_id": "17N.2.SL.TZ0.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Ten students were asked for the distance, in km, from their home to school. Their responses are recorded below.

\n

0.3         0.4         3         3         3.5         5         7         8         8         10

\n
\n

The following box-and-whisker plot represents this data.

\n

\n
\n

For these data, find the mean distance from a student’s home to school.

\n
[2]
\n
a.
\n
\n

Find the value of p .

\n
[1]
\n
b.
\n
\n

Find the interquartile range.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of finding  x n         (M1)

\n

eg     0.3 + 0.4 + 3 + + 10 10 ,   48.2 10

\n

x ¯ = 4.82   (exact)       A1  N2

\n

[2 marks]

\n
a.
\n
\n

p = 4.25  (exact)       A1  N1

\n

[1 mark]

\n
b.
\n
\n

valid approach      (M1)

\n

eg   Q3 − Q1  3 − 8 ,  3 to 8

\n

IQR = 5         A1  N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.SL.TZ1.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

The following Venn diagram shows the sets \nA\n, \nB\n, \nC\n and \nU\n.

\n

\nx\n is an element of \nU\n.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/03\"

\n
\n

In the table indicate whether the given statements are True or False.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/03.a\"

\n
[5]
\n
a.
\n
\n

On the Venn diagram, shade the region A ( B C ) .

\n
[1]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/03.a/M\"     (A1)(A1)(A1)(A1)(A1)     (C5)

\n

[5 marks]

\n
a.
\n
\n

\"N16/5/MATSD/SP1/ENG/TZ0/03.b/M\"     (A1)     (C1)

\n

[1 mark]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A group of 10 girls recorded the number of hours they spent watching television during a particular week. Their results are summarized in the box-and-whisker plot below.

\n

\n
\n

The group of girls watched a total of 180 hours of television.

\n
\n

A group of 20 boys also recorded the number of hours they spent watching television that same week. Their results are summarized in the table below.

\n

\n
\n

The following week, the group of boys had exams. During this exam week, the boys spent half as much time watching television compared to the previous week.

\n

For this exam week, find

\n
\n

The range of the data is 16. Find the value of a .

\n
[2]
\n
a.
\n
\n

Find the value of the interquartile range.

\n
[2]
\n
b.
\n
\n

Find the mean number of hours that the girls in this group spent watching television that week.

\n
[2]
\n
c.
\n
\n

Find the total number of hours the group of boys spent watching television that week.

\n
[2]
\n
d.i.
\n
\n

Find the mean number of hours that all 30 girls and boys spent watching television that week.

\n
[3]
\n
d.ii.
\n
\n

the mean number of hours that the group of boys spent watching television.

\n
[2]
\n
e.i.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

valid approach       (M1)

\n

eg    16 + 8,  a − 8

\n

24 (hours)       A1 N2

\n

[2 marks]

\n
a.
\n
\n

valid approach       (M1)

\n

eg    20 − 15,  Q 3 Q 1 ,  15 − 20

\n

IQR = 5       A1 N2

\n

[2 marks]

\n
b.
\n
\n

correct working      (A1)

\n

eg     180 10 ,   180 n ,   x 10

\n

mean = 18 (hours)      A1 N2

\n

[2 marks]

\n
c.
\n
\n

attempt to find total hours for group B     (M1)

\n

eg     x ¯ × n

\n

group B total hours = 420  (seen anywhere)     A1 N2

\n

[2 marks]

\n
d.i.
\n
\n

attempt to find sum for combined group (may be seen in working)      (M1)

\n

eg    180 + 420,  600

\n

correct working        (A1)

\n

eg    180 + 420 30 600 30

\n

mean = 20 (hours)    A1 N2

\n

[3 marks]

\n
d.ii.
\n
\n

valid approach to find the new mean     (M1)

\n

eg    1 2 μ 1 2 × 21  

\n

mean = 21 2  (= 10.5) hours    A1 N2

\n

[2 marks]

\n
e.i.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.i.
\n
", "question_id": "19M.1.SL.TZ2.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

Dune Canyon High School organizes its school year into three trimesters: fall/autumn (\nF\n), winter (\nW\n) and spring (\nS\n). The school offers a variety of sporting activities during and outside the school year.

\n

The activities offered by the school are summarized in the following Venn diagram.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/04\"

\n
\n

Write down the number of sporting activities offered by the school during its school year.

\n
[1]
\n
a.
\n
\n

Determine whether rock-climbing is offered by the school in the fall/autumn trimester.

\n
[1]
\n
b.
\n
\n

Write down the elements of the set F W ;

\n
[1]
\n
c.i.
\n
\n

Write down n ( W S ) .

\n
[1]
\n
c.ii.
\n
\n

Write down, in terms of F , W and S , an expression for the set which contains only archery, baseball, kayaking and surfing.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

15     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

no     (A1)     (C1)

\n

 

\n

Note:     Accept “it is only offered in Winter and Spring”.

\n

 

\n

[1 mark]

\n
b.
\n
\n

volleyball, golf, cycling     (A1)     (C1)

\n

 

\n

Note:     Responses must list all three sports for the (A1) to be awarded.

\n

 

\n

[1 mark]

\n
c.i.
\n
\n

4     (A1)     (C1)

\n

[1 mark]

\n
c.ii.
\n
\n

( F W S ) OR F W S (or equivalent)     (A2)     (C2)

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.1.SL.TZ1.T_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A group of 66 people went on holiday to Hawaii. During their stay, three trips were arranged: a boat trip (\nB\n), a coach trip (\nC\n) and a helicopter trip (\nH\n).

\n

From this group of people:

\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n
went on all three trips;
16 went on the coach trip only;
13 went on the boat trip only;
went on the helicopter trip only;
went on the coach trip and the helicopter trip but not the boat trip;
2\nwent on the boat trip and the helicopter trip but not the coach trip;
4\nwent on the boat trip and the coach trip but not the helicopter trip;
did not go on any of the trips.
\n
\n

One person in the group is selected at random.

\n
\n

Draw a Venn diagram to represent the given information, using sets labelled \nB\n, \nC\n and \nH\n.

\n
[5]
\n
a.
\n
\n

Show that \nx\n=\n3\n.

\n
[2]
\n
b.
\n
\n

Write down the value of \nn\n(\nB\n\nC\n)\n.

\n
[1]
\n
c.
\n
\n

Find the probability that this person

\n

(i)     went on at most one trip;

\n

(ii)     went on the coach trip, given that this person also went on both the helicopter trip and the boat trip.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\"N16/5/MATSD/SP2/ENG/TZ0/02.a/M\"     (A5)

\n

 

\n

Notes:     Award (A1) for rectangle and three labelled intersecting circles (U need not be seen),

\n

(A1) for 3 in the correct region,

\n

(A1) for 8 in the correct region,

\n

(A1) for 5, 13 and 16 in the correct regions,

\n

(A1) for \nx\n, \n2\nx\n and \n4\nx\n in the correct regions.

\n

 

\n

[5 marks]

\n
a.
\n
\n

\n8\n+\n13\n+\n16\n+\n3\n+\n5\n+\nx\n+\n2\nx\n+\n4\nx\n=\n66\n    (M1)

\n

 

\n

Note:     Award (M1) for either a completely correct equation or adding all the terms from their diagram in part (a) and equating to 66.

\n

Award (M0)(A0) if their equation has no \nx\n.

\n

 

\n

\n7\nx\n=\n66\n\n45\n OR \n7\nx\n+\n45\n=\n66\n     (A1)

\n

 

\n

Note:     Award (A1) for adding their like terms correctly, but only when the solution to their equation is equal to 3 and is consistent with their original equation.

\n

 

\n

\nx\n=\n3\n    (AG)

\n

 

\n

Note:     The conclusion \nx\n=\n3\n must be seen for the (A1) to be awarded.

\n

 

\n

[2 marks]

\n
b.
\n
\n

15     (A1)(ft)

\n

 

\n

Note:     Follow through from part (a). The answer must be an integer.

\n

 

\n

[1 mark]

\n
c.
\n
\n

(i)     \n\n\n42\n\n\n66\n\n\n\n \n\n\n(\n\n\n7\n\n11\n\n\n,\n\n \n\n0.636\n,\n\n \n\n63.6\n%\n\n)\n\n     (A1)(ft)(A1)(G2)

\n

 

\n

Note:     Award (A1)(ft) for numerator, (A1) for denominator. Follow through from their Venn diagram.

\n

 

\n

(ii)     \n\n3\n9\n\n\n \n\n\n(\n\n\n1\n3\n\n,\n\n \n\n0.333\n,\n\n \n\n33.3\n%\n\n)\n\n     (A1)(A1)(ft)(G2)

\n

 

\n

Note:     Award (A1) for numerator, (A1)(ft) for denominator. Follow through from their Venn diagram.

\n

 

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "16N.2.SL.TZ0.T_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

160 students attend a dual language school in which the students are taught only in Spanish or taught only in English.

\n

A survey was conducted in order to analyse the number of students studying Biology or Mathematics. The results are shown in the Venn diagram.

\n

 

\n

Set S represents those students who are taught in Spanish.

\n

Set B represents those students who study Biology.

\n

Set M represents those students who study Mathematics.

\n

 

\n

\n
\n

A student from the school is chosen at random.

\n
\n

Find the number of students in the school that are taught in Spanish.

\n
[2]
\n
a.i.
\n
\n

Find the number of students in the school that study Mathematics in English.

\n
[2]
\n
a.ii.
\n
\n

Find the number of students in the school that study both Biology and Mathematics.

\n
[2]
\n
a.iii.
\n
\n

Write down \nn\n\n(\n\nS\n\n\n(\n\nM\n\nB\n\n)\n\n\n)\n\n.

\n
[1]
\n
b.i.
\n
\n

Write down \nn\n\n(\n\nB\n\nM\n\n\nS\n\n\n\n)\n\n.

\n
[1]
\n
b.ii.
\n
\n

Find the probability that this student studies Mathematics.

\n
[2]
\n
c.i.
\n
\n

Find the probability that this student studies neither Biology nor Mathematics.

\n
[2]
\n
c.ii.
\n
\n

Find the probability that this student is taught in Spanish, given that the student studies Biology.

\n
[2]
\n
c.iii.
\n
", "Markscheme": "
\n

10 + 40 + 28 + 17      (M1)

\n

= 95       (A1)(G2)

\n

 

\n

Note: Award (M1) for each correct sum (for example: 10 + 40 + 28 + 17) seen.

\n

[2 marks]

\n
a.i.
\n
\n

20 + 12      (M1)

\n

= 32       (A1)(G2)

\n

 

\n

Note: Award (M1) for each correct sum (for example: 10 + 40 + 28 + 17) seen.

\n

[2 marks]

\n
a.ii.
\n
\n

12 + 40      (M1)

\n

= 52       (A1)(G2)

\n

 

\n

Note: Award (M1) for each correct sum (for example: 10 + 40 + 28 + 17) seen.

\n

[2 marks]

\n
a.iii.
\n
\n

78      (A1)

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

12      (A1)

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

\n\n\n100\n\n\n160\n\n\n   \n\n(\n\n\n5\n8\n\n\n,\n\n\n\n0.625\n\n,\n\n\n\n62.5\n\n\n\n\n\n)\n\n      (A1)(A1) (G2)

\n

 

\n

Note: Throughout part (c), award (A1) for correct numerator, (A1) for correct denominator. All answers must be probabilities to award (A1).

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

\n\n\n42\n\n\n160\n\n\n  \n\n(\n\n\n\n21\n\n\n80\n\n\n\n,\n\n\n\n0.263\n\n\n\n(\n\n0.2625\n\n)\n\n\n,\n\n\n\n26.3\n\n\n\n\n\n\n\n(\n\n26.25\n\n\n\n\n\n)\n\n\n)\n\n      (A1)(A1) (G2)

\n

 

\n

Note: Throughout part (c), award (A1) for correct numerator, (A1) for correct denominator. All answers must be probabilities to award (A1).

\n

 

\n

[2 marks]

\n
c.ii.
\n
\n

\n\n\n50\n\n\n70\n\n\n  \n\n(\n\n\n5\n7\n\n\n,\n\n\n\n0.714\n\n\n\n(\n\n0.714285\n\n\n)\n\n\n,\n\n\n\n71.4\n\n\n\n\n\n\n\n(\n\n71.4285\n\n\n\n\n\n\n)\n\n\n)\n\n     (A1)(A1) (G2)

\n

 

\n

Note: Throughout part (c), award (A1) for correct numerator, (A1) for correct denominator. All answers must be probabilities to award (A1).

\n

 

\n

[2 marks]

\n
c.iii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
", "question_id": "18N.2.SL.TZ0.T_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

The functions f and g are defined for x by fx=6x2-12x+1 and gx=-x+c, where c.

\n
\n

Find the range of f.

\n
[2]
\n
a.
\n
\n

Given that gfx0 for all x, determine the set of possible values for c.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

attempting to find the vertex      (M1)

\n

x=1 OR  y=-5  OR  fx=6x-12-5

\n

range is y-5              A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

gfx=-6x2-12x+1+c  =-6x-12-5+c            (A1)

\n


EITHER

\n

relating to the range of f OR attempting to find g-5            (M1)

\n

5+c0            (A1)

\n


OR

\n

attempting to find the discriminant of gfx            (M1)

\n

144+24c-10  120+24c0            (A1)

\n


THEN

\n

c-5             A1

\n

 

\n

METHOD 2

\n

vertical reflection followed by vertical shift             (M1)

\n

new vertex is 1,5+c            (A1)

\n

5+c0            (A1)

\n

c-5             A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.SL.TZ2.5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection", "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

A data set has n items. The sum of the items is 800 and the mean is 20.

\n
\n

The standard deviation of this data set is 3. Each value in the set is multiplied by 10.

\n
\n

Find n.

\n
[2]
\n
a.
\n
\n

Write down the value of the new mean.

\n
[1]
\n
b.i.
\n
\n

Find the value of the new variance.

\n
[3]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct approach      (A1)

\n

eg  \n\n\n800\n\nn\n\n=\n20\n

\n

40      A1 N2

\n

[2 marks]

\n
a.
\n
\n

200   A1 N1

\n

[1 mark]

\n
b.i.
\n
\n

METHOD 1

\n

recognizing variance = σ 2      (M1)

\n

eg  32 = 9

\n

correct working to find new variance      (A1)

\n

eg  σ × 102, 9 × 100

\n

900      A1 N3

\n

 

\n

METHOD 2

\n

new standard deviation is 30      (A1)

\n

recognizing variance = σ 2      (M1)

\n

eg 32 = 9, 302

\n

900      A1 N3

\n

[3 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18M.1.SL.TZ2.S_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

A lampshade, in the shape of a cone, has a wireframe consisting of a circular ring and four straight pieces of equal length, attached to the ring at points A, B, C and D.

\n

The ring has its centre at point O and its radius is 20 centimetres. The straight pieces meet at point V, which is vertically above O, and the angle they make with the base of the lampshade is 60°.

\n

This information is shown in the following diagram.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/03\"

\n
\n

Find the length of one of the straight pieces in the wireframe.

\n
[2]
\n
a.
\n
\n

Find the total length of wire needed to construct this wireframe. Give your answer in centimetres correct to the nearest millimetre.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

cos 60 = 20 b OR b = 20 cos 60     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into a correct trig. ratio.

\n

( b = )  40 (cm)     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

4 × 40 + 2 π ( 20 )     (M1)(M1)

\n

 

\n

Note:     Award (M1) for correct substitution in the circumference of the circle formula, (M1) for adding 4 times their answer to part (a) to their circumference of the circle.

\n

 

\n

285.6637…     (A1)(ft)

\n

 

\n

Note:     Follow through from part (a). This (A1) may be implied by a correct rounded answer.

\n

 

\n

285.7 (cm)     (A1)(ft)     (C4)

\n

 

\n

Notes:     Award (A1)(ft) for rounding their answer (consistent with their method) to the nearest millimetre, irrespective of unrounded answer seen.

\n

The final (A1)(ft) is not dependent on any of the previous M marks. It is for rounding their unrounded answer correctly.

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ2.T_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Two events A and B are such that P(A) = 0.62 and P\n\n(\n\nA\n\nB\n\n)\n\n = 0.18.

\n
\n

Find P(AB′ ).

\n
[2]
\n
a.
\n
\n

Given that P((AB)′) = 0.19, find P(A |B).

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

valid approach

\n

eg  Venn diagram, P(A) − P (AB), 0.62 − 0.18      (M1)

\n

P(AB' ) = 0.44      A1 N2

\n

[2 marks]

\n
a.
\n
\n

valid approach to find either P(B′ ) or P(B)      (M1)

\n

eg   (seen anywhere), 1 − P(A ∩ B) − P((A ∪ B)′)

\n

correct calculation for P(B′ ) or P(B)      (A1)

\n

eg  0.44 + 0.19, 0.81 − 0.62 + 0.18

\n

correct substitution into  P ( A B ) P ( B )       (A1)

\n

eg   0.44 0.19 + 0.44 , 0.44 1 0.37

\n

0.698412

\n

P(A |B) =  44 63   (exact), 0.698     A1 N3

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.SL.TZ1.S_5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

All living plants contain an isotope of carbon called carbon-14. When a plant dies, the isotope decays so that the amount of carbon-14 present in the remains of the plant decreases. The time since the death of a plant can be determined by measuring the amount of carbon-14 still present in the remains.

\n

The amount, A, of carbon-14 present in a plant t years after its death can be modelled by A=A0e-kt where t0 and A0, k are positive constants.

\n

At the time of death, a plant is defined to have 100 units of carbon-14.

\n
\n

The time taken for half the original amount of carbon-14 to decay is known to be 5730 years.

\n
\n

Show that A0=100.

\n
[1]
\n
a.
\n
\n

Show that k=ln25730.

\n
[3]
\n
b.
\n
\n

Find, correct to the nearest 10 years, the time taken after the plant’s death for 25% of the carbon-14 to decay.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

100=A0e0             A1

\n

A0=100             AG

\n

 

\n

[1 mark]

\n
a.
\n
\n

correct substitution of values into exponential equation             (M1)

\n

50=100e-5730k  OR  e-5730k=12

\n


EITHER

\n

-5730k=ln12             A1

\n

ln12=-ln2  OR  -ln12=ln2             A1

\n


OR

\n

e5730k=2             A1

\n

5730k=ln2             A1

\n


THEN

\n

k=ln25730             AG

\n


Note:
There are many different ways of showing that k=ln25730 which involve showing different steps. Award full marks for at least two correct algebraic steps seen.

\n

 

\n

[3 marks]

\n
b.
\n
\n

if 25% of the carbon-14 has decayed, 75% remains ie, 75 units remain                      (A1)

\n

75=100e-ln25730t

\n


EITHER

\n

using an appropriate graph to attempt to solve for t                      (M1)

\n


OR

\n

manipulating logs to attempt to solve for t                               (M1)

\n

ln0.75=-ln25730t

\n

t=2378.164

\n


THEN

\n

t=2380 (years) (correct to the nearest 10 years)                   A1

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.2.SL.TZ2.6", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-9-exponential-and-logarithmic-functions" ] }, { "Question": "
\n

The final examination results obtained by a group of 3200 Biology students are summarized on the cumulative frequency graph.

\n

\n
\n

350 of the group obtained the highest possible grade in the examination.

\n
\n

The grouped frequency table summarizes the examination results of this group of students.

\n

\n
\n

Find the median of the examination results.

\n
[2]
\n
a.i.
\n
\n

Find the interquartile range.

\n
[3]
\n
a.ii.
\n
\n

Find the final examination result required to obtain the highest possible grade.

\n
[2]
\n
b.
\n
\n

Write down the modal class.

\n
[2]
\n
c.i.
\n
\n

Write down the mid-interval value of the modal class.

\n
[1]
\n
c.ii.
\n
\n

Calculate an estimate of the mean examination result.

\n
[2]
\n
d.i.
\n
\n

Calculate an estimate of the standard deviation, giving your answer correct to three decimal places.

\n
[1]
\n
d.ii.
\n
\n

The teacher sets a grade boundary that is one standard deviation below the mean.

\n

Use the cumulative frequency graph to estimate the number of students whose final examination result was below this grade boundary.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

60     (A2)

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

68 − 48     (A1)(M1)

\n

Note: Award (A1) for two correct quartiles seen, (M1) for finding the difference between their two quartiles.

\n

 

\n

= 20      (A1)(ft)(G3)

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

3200 − 350 = 2850      (M1)

\n

Note: Award (M1) for 2850 seen. Follow through from their 3200.

\n

 

\n

(Top grade boundary =) 76        (A1)(ft)(G2)

\n

 

\n

[2 marks]

\n
b.
\n
\n

60 < x ≤ 80     (A1)(A1)

\n

Note: Award (A1) for 60, 80 seen, (A1) for correct strict and weak inequalities.

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

70     (A1)(ft)

\n

Note: Follow through from part (c)(i).

\n

 

\n

[1 mark]

\n
c.ii.
\n
\n

57.2   (57.1875)     (A2)(ft)

\n

Note: Follow through from part (c)(ii).

\n

 

\n

[2 marks]

\n
d.i.
\n
\n

18.496     (A1)

\n

Note: Award (A0) for 18.499.

\n

 

\n

[1 mark]

\n
d.ii.
\n
\n

57.2 − 18.5      (M1)

\n

= 38.7  (38.6918…)       (A1)(ft)

\n

Note: Award (M1) for subtracting their standard deviation from their mean. Follow through from part (d) even if no working is shown.

\n

 

\n

450 (students)       (A1)(ft)(G2)

\n

Note: Accept any answer within the range of 450 to 475, inclusive. Follow through from part (d), adjusting the acceptable range as necessary.

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "18N.2.SL.TZ0.T_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

A city hired 160 employees to work at a festival. The following cumulative frequency curve shows the number of hours employees worked during the festival.

\n

\"M17/5/MATME/SP1/ENG/TZ2/08.a.ii\"

\n
\n

The city paid each of the employees £8 per hour for the first 40 hours worked, and £10 per hour for each hour they worked after the first 40 hours.

\n
\n

Find the median number of hours worked by the employees.

\n
[2]
\n
a.i.
\n
\n

Write down the number of employees who worked 50 hours or less.

\n
[1]
\n
a.ii.
\n
\n

Find the amount of money an employee earned for working 40 hours;

\n
[1]
\n
b.i.
\n
\n

Find the amount of money an employee earned for working 43 hours.

\n
[3]
\n
b.ii.
\n
\n

Find the number of employees who earned £200 or less.

\n
[3]
\n
c.
\n
\n

Only 10 employees earned more than £\nk\n. Find the value of \nk\n.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

evidence of median position     (M1)

\n

eg\n\n\n\n\n\n80th employee

\n

40 hours     A1     N2

\n

[2 marks]

\n
a.i.
\n
\n

130 employees     A1     N1

\n

[1 mark]

\n
a.ii.
\n
\n

£320     A1     N1

\n

[1 mark]

\n
b.i.
\n
\n

splitting into 40 and 3     (M1)

\n

eg\n\n\n\n\n\n3 hours more, \n3\n×\n10\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n320\n+\n3\n×\n10\n

\n

£350     A1     N3

\n

[3 marks]

\n
b.ii.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n200 is less than 320 so 8 pounds/hour, \n200\n÷\n8\n,\n\n \n\n25\n,\n\n \n\n\n\n200\n\n\n320\n\n\n=\n\nx\n\n40\n\n\n,

\n

18 employees     A2     N3

\n

[3 marks]

\n
c.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n160\n\n10\n

\n

60 hours worked     (A1)

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n40\n(\n8\n)\n+\n20\n(\n10\n)\n,\n\n \n\n320\n+\n200\n

\n

\nk\n=\n520\n     A1     N3

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.1.SL.TZ2.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

A flat horizontal area, ABC, is such that AB = 100 m , BC = 50 m and angle AĈB = 43.7° as shown in the diagram.

\n

\n
\n

Show that the size of angle BÂC is 20.2°, correct to 3 significant figures.

\n
[3]
\n
a.
\n
\n

Calculate the area of triangle ABC.

\n
[4]
\n
b.
\n
\n

Find the length of AC.

\n
[3]
\n
c.
\n
\n

A vertical pole, TB, is constructed at point B and has height 25 m.

\n

Calculate the angle of elevation of T from, M, the midpoint of the side AC.

\n

 

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

sin 43.7 100 = sin BAC 50       (M1)(A1)

\n

Note: Award (M1) for substitution into sine rule formula, (A1) for correct substitution.

\n

 

\n

BAC = 20.2087… = 20.2°      (A1)(AG)

\n

Note: Award (A1) only if both the correct unrounded and rounded answers are seen.

\n

 

\n

[3 marks]

\n

 

\n
a.
\n
\n

units are required in part (b)

\n

 

\n

1 2 ( 100 ) ( 50 ) sin ( 116.1 )       (A1)(M1)(A1)

\n

Note: Award (A1) for 116.1 or unrounded value or 116 seen, (M1) for substitution into area of triangle formula, (A1) for correct substitution.

\n

 

\n

 

\n

= 2250 m2  (2245.06… m2)      (A1)(G3)

\n

Note: The answer is 2250 m2; the units are required. Use of 20.2087… gives 2245.23….

\n

 

\n

[4 marks]

\n
b.
\n
\n

100 sin 43.7 = AC sin ( 116.1 )      (M1)(A1)(ft)

\n

Note: Award (M1) for substitution into sine rule formula, (A1)(ft) for their correct substitution. Follow through from their 116.1.

\n

 

\n

AC = 130 (m)  (129.982… (m))      (A1)(ft)(G2)

\n

Note: Use of 20.2087… gives 129.992….

\n

 

\n

OR

\n

AC2 = 1002 + 502 −2(100)(50) cos (116.1)      (M1)(A1)(ft)

\n

Note: Award (M1) for substitution into cosine rule formula, (A1)(ft) for their correct substitution. Follow through from their 116.1.

\n

 

\n

AC = 130 (m)  (129.997… (m))      (A1)(ft)(G2)

\n

Note:  Award (M1) for substitution into cosine rule formula, (A1)(ft) for their correct substitution.

\n

 

\n

[3 marks]

\n
c.
\n
\n

 

\n

BM2 = 1002 + 652 − 2(100)(65) cos (20.2°)      (M1)(A1)(ft)

\n

OR

\n

BM2 = 502 + 652 − 2(50)(65) cos (43.7°)      (M1)(A1)(ft)

\n

Note: Award (M1) for substitution into cosine rule formula, (A1)(ft) for correct substitution, including half their AC.

\n

 

\n

BM = 45.0 (44.9954… OR 45.0079…)      (A1)(ft)

\n

Note: Use of 20.2052… gives 45. Award (G2) for 45.0 seen without working.

\n

 

\n

tan ( TMB ) = 25 their BM       (M1)

\n

Note: Award (M1) for correct substitution into tangent formula.

\n

 

\n

T M B = 29.1°  (29.0546…°)       (A1)(ft)(G4)

\n

Note: Follow through within part (d) provided their BM is seen. Use of 44.9954 gives 29.0570… and use of 45.0079… gives 29.0503…. Follow through from their AC in part (c).

\n

 

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18N.2.SL.TZ0.T_5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A school café sells three flavours of smoothies: mango (\nM\n), kiwi fruit (\nK\n) and banana (\nB\n).
85 students were surveyed about which of these three flavours they like.

\n

35 students liked mango, 37 liked banana, and 26 liked kiwi fruit
2 liked all three flavours
20 liked both mango and banana
14 liked mango and kiwi fruit
3 liked banana and kiwi fruit

\n
\n

Using the given information, complete the following Venn diagram.

\n

\n
[2]
\n
a.
\n
\n

Find the number of surveyed students who did not like any of the three flavours.

\n
[2]
\n
b.
\n
\n

A student is chosen at random from the surveyed students.

\n

Find the probability that this student likes kiwi fruit smoothies given that they like mango smoothies.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

    (A1)(A1) (C2)

\n

Note: Award (A1) for 18, 12 and 1 in correct place on Venn diagram, (A1) for 3, 16 and 11 in correct place on Venn diagram.

\n

[2 marks]

\n
a.
\n
\n

85 − (3 + 16 + 11 + 18 + 12 + 1 + 2)      (M1)

\n

Note: Award (M1) for subtracting the sum of their values from 85.

\n

22      (A1)(ft)  (C2)

\n

Note: Follow through from their Venn diagram in part (a).
If any numbers that are being subtracted are negative award (M1)(A0).

\n

[2 marks]

\n
b.
\n
\n

\n\n\n14\n\n\n35\n\n\n\n\n\n\n(\n\n\n2\n5\n\n\n,\n\n\n\n0.4\n\n,\n\n\n\n40\n\n\n\n\n)\n\n     (A1)(ft)(A1)(ft)  (C2)

\n

Note: Award (A1) for correct numerator; (A1) for correct denominator. Follow through from their Venn diagram.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A continuous random variable X has the probability density function fn given by

\n

fnx=n+1xn,     0,  0x1otherwise

\n

where n, n0.

\n
\n

Show that EX=n+1n+2.

\n
[2]
\n
a.
\n
\n

Show that VarX=n+1n+22n+3.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

EX=n+101xn+1dx                       M1

\n

=n+1xn+2n+201                         A1

\n

leading to EX=n+1n+2                   AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

use of VarX=EX2-EX2                  M1

\n

VarX=n+101xn+2dx-n+1n+22

\n

=n+11n+3xn+301-n+1n+22

\n

=n+1n+3-n+1n+22                       A1

\n

=n+1n+22-n+12n+3n+22n+3                  M1

\n


EITHER

\n

=n+1n2+4n+4-n2+4n+3n+22n+3                       A1

\n


OR

\n

=n3+5n2+8n+4-n3+5n2+7n+3n+22n+3                       A1

\n


THEN

\n

so VarX=n+1n+22n+3                       AG

\n

 

\n

METHOD 2

\n

use of VarX=EX-EX2                  M1

\n

VarX=n+101x-n+1n+22xndx

\n

=n+11n+3xn+3-2n+1n+22xn+2+n+1n+22xn+101

\n

=n+1n+3-n+1n+22                       A1

\n

=n+1n+22-n+1n+3n+22n+3                  M1

\n


EITHER

\n

=n+1n2+4n+4-n2+4n+3n+22n+3                       A1

\n


OR

\n

=n3+5n2+8n+4-n3+5n2+7n+3n+22n+3                       A1

\n


THEN

\n

so VarX=n+1n+22n+3                       AG

\n

 

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.AHL.TZ2.6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "ahl-4-14-properties-of-discrete-and-continuous-random-variables" ] }, { "Question": "
\n

The six blades of a windmill rotate around a centre point C. Points A and B and the base of the windmill are on level ground, as shown in the following diagram.

\n

\n

From point A the angle of elevation of point C is 0.6 radians.

\n
\n

An observer walks 7 metres from point A to point B.

\n
\n

The observer keeps walking until he is standing directly under point C. The observer has a height of 1.8 metres, and as the blades of the windmill rotate, the end of each blade passes 2.5 metres over his head.

\n
\n

One of the blades is painted a different colour than the others. The end of this blade is labelled point D. The height h, in metres, of point D above the ground can be modelled by the function ht=pcos3π10t+q, where t is in seconds and p, q. When t=0, point D is at its maximum height.

\n
\n

Given that point A is 12 metres from the base of the windmill, find the height of point C above the ground.

\n
[2]
\n
a.
\n
\n

Find the angle of elevation of point C from point B.

\n
[2]
\n
b.
\n
\n

Find the length of each blade of the windmill.

\n
[2]
\n
c.
\n
\n

Find the value of p and the value of q.

\n
[4]
\n
d.
\n
\n

If the observer stands directly under point C for one minute, point D will pass over his head n times.

\n

Find the value of n.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

tan0.6=h12                     (M1)

\n

8.20964

\n

8.21m                  A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

tanB=8.20965  OR  tan-11.6419                     (A1)

\n

1.02375

\n

1.02  (radians) (accept 58.7°)                  A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

x+1.8+2.5=8.20964  (or equivalent)                     (A1)

\n

3.90964

\n

3.91  (m)                  A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

METHOD 1

\n

recognition that blade length = amplitude, p=max-min2                     (M1)

\n

p=3.91                  A1

\n

centre of windmill = vertical shift, q=max+min2                     (M1)

\n

q=8.21                  A1

\n

 

\n

METHOD 2

\n

attempting to form two equations in terms of  p and q                     (M1)(M1)

\n

12.1192=pcos3π10·0+q,  4.3000=pcos3π10·103+q

\n

p=3.91                  A1

\n

q=8.21                  A1

\n

  

\n

[4 marks]

\n
d.
\n
\n

appropriate working towards finding the period                     (M1)

\n

period=2π3π10=6.6666

\n

rotations per minute =60their period                     (M1)

\n

n=9 (must be an integer) (accept n=10, n=18, n=19)                  A1

\n

  

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.2.SL.TZ2.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-3-applications-angles-of-elevation-and-depression-bearings", "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

A company performs an experiment on the efficiency of a liquid that is used to detect a nut allergy.

\n

A group of 60 people took part in the experiment. In this group 26 are allergic to nuts. One person from the group is chosen at random.

\n
\n

A second person is chosen from the group.

\n
\n

When the liquid is added to a person’s blood sample, it is expected to turn blue if the person is allergic to nuts and to turn red if the person is not allergic to nuts.

\n

The company claims that the probability that the test result is correct is 98% for people who are allergic to nuts and 95% for people who are not allergic to nuts.

\n

It is known that 6 in every 1000 adults are allergic to nuts.

\n

This information can be represented in a tree diagram.

\n

\"N17/5/MATSD/SP2/ENG/TZ0/04.c.d.e.f.g\"

\n
\n

An adult, who was not part of the original group of 60, is chosen at random and tested using this liquid.

\n
\n

The liquid is used in an office to identify employees who might be allergic to nuts. The liquid turned blue for 38 employees.

\n
\n

Find the probability that both people chosen are not allergic to nuts.

\n
[2]
\n
b.
\n
\n

Copy and complete the tree diagram.

\n
[3]
\n
c.
\n
\n

Find the probability that this adult is allergic to nuts and the liquid turns blue.

\n
[2]
\n
d.
\n
\n

Find the probability that the liquid turns blue.

\n
[3]
\n
e.
\n
\n

Find the probability that the tested adult is allergic to nuts given that the liquid turned blue.

\n
[3]
\n
f.
\n
\n

Estimate the number of employees, from this 38, who are allergic to nuts.

\n
[2]
\n
g.
\n
", "Markscheme": "
\n

\n\n\n34\n\n\n60\n\n\n×\n\n\n33\n\n\n59\n\n\n     (M1)

\n

 

\n

Note:    Award (M1) for their correct product.

\n

 

\n

\n=\n0.317\n\n \n\n\n(\n\n\n\n187\n\n\n590\n\n\n,\n\n \n\n0.316949\n\n,\n\n \n\n31.7\n%\n\n)\n\n     (A1)(ft)(G2)

\n

 

\n

Note:    Follow through from part (a).

\n

 

\n

[2 marks]

\n
b.
\n
\n

\"N17/5/MATSD/SP2/ENG/TZ0/04.c/M\"     (A1)(A1)(A1)

\n

 

\n

Note:     Award (A1) for each correct pair of branches.

\n

 

\n

[3 marks]

\n
c.
\n
\n

\n0.006\n×\n0.98\n     (M1)

\n

 

\n

Note:     Award (M1) for multiplying 0.006 by 0.98.

\n

 

\n

\n=\n0.00588\n\n \n\n\n(\n\n\n\n147\n\n\n25000\n\n\n,\n\n \n\n0.588\n%\n\n)\n\n     (A1)(G2)

\n

[2 marks]

\n
d.
\n
\n

\n0.006\n×\n0.98\n+\n0.994\n×\n0.05\n\n \n\n(\n0.00588\n+\n0.994\n×\n0.05\n)\n     (A1)(ft)(M1)

\n

 

\n

Note:     Award (A1)(ft) for their two correct products, (M1) for adding two products.

\n

 

\n

\n=\n0.0556\n\n \n\n\n(\n\n0.05558\n,\n\n \n\n5.56\n%\n,\n\n \n\n\n\n2779\n\n\n50000\n\n\n\n)\n\n     (A1)(ft)(G3)

\n

 

\n

Note:     Follow through from parts (c) and (d).

\n

 

\n

[3 marks]

\n
e.
\n
\n

\n\n\n0.006\n×\n0.98\n\n\n0.05558\n\n\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for their correct numerator, (M1) for their correct denominator.

\n

 

\n

\n=\n0.106\n\n \n\n\n(\n\n0.105793\n\n,\n\n \n\n10.6\n%\n,\n\n \n\n\n\n42\n\n\n397\n\n\n\n)\n\n     (A1)(ft)(G3)

\n

 

\n

Note:     Follow through from parts (d) and (e).

\n

 

\n

[3 marks]

\n
f.
\n
\n

\n0.105793\n\n×\n38\n     (M1)

\n

 

\n

Note:     Award (M1) for multiplying 38 by their answer to part (f).

\n

 

\n

\n=\n4.02\n\n \n\n(\n4.02015\n\n)\n     (A1)(ft)(G2)

\n

 

\n

Notes: Follow through from part (f). Use of 3 sf result from part (f) results in an answer of 4.03 (4.028).

\n

 

\n

[2 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "17N.2.SL.TZ0.T_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Eight runners compete in a race where there are no tied finishes. Andrea and Jack are two of the eight competitors in this race.

\n

Find the total number of possible ways in which the eight runners can finish if Jack finishes

\n
\n

in the position immediately after Andrea.

\n
[2]
\n
a.
\n
\n

in any position after Andrea.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

Jack and Andrea finish in that order (as a unit) so we are considering the arrangement of 7 objects               (M1)

\n

7! =5040 ways                      A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

the number of ways that Andrea finishes in front of Jack is equal to the number of ways that Jack finishes in front of Andrea            (M1)

\n

total number of ways is 8!                   (A1)

\n

8!2 =20160  ways             A1

\n

 

\n

METHOD 2

\n

the other six runners can finish in 6! =720 ways               (A1)

\n

when Andrea finishes first, Jack can finish in 7 different positions

\n

when Andrea finishes second, Jack can finish in 6 different positions etc

\n

7+6+5+4+3+2+1 (=28) ways             (A1)

\n

hence there are (7+6+5+4+3+2+1)×6! ways

\n

28×6! (=20160) ways              A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21M.2.AHL.TZ2.7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

A buoy is floating in the sea and can be seen from the top of a vertical cliff. A boat is travelling from the base of the cliff directly towards the buoy.

\n

The top of the cliff is 142 m above sea level. Currently the boat is 100 metres from the buoy and the angle of depression from the top of the cliff to the boat is 64°.

\n

\n
\n

Draw and label the angle of depression on the diagram.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

  (A1)   (C1)

\n

Note: The horizontal line must be shown and the angle of depression must be labelled. Accept a numerical or descriptive label.

\n

[1 mark]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.SL.TZ1.T_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Consider z=cosθ+isinθ where z, z1.

\n

Show that Re1+z1-z=0.

\n
", "Markscheme": "
\n

1+z1-z=1+cosθ+isinθ1-cosθ-isinθ

\n

attempt to use the complex conjugate of their denominator           M1

\n

=1+cosθ+isinθ1-cosθ+isinθ1-cosθ-isinθ1-cosθ+isinθ            A1

\n

Re1+z1-z=1-cos2θ-sin2θ1-cosθ2+sin2θ  =1-cos2θ-sin2θ2-2cosθ          M1A1

\n


Note:
Award M1 for expanding the numerator and A1 for a correct numerator. Condone either an incorrect denominator or the absence of a denominator.

\n


using cos2θ+sin2θ=1 to simplify the numerator           (M1)

\n

Re1+z1-z=0            AG

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21M.2.AHL.TZ2.8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

Write down the first three terms of the binomial expansion of (1+t)-1 in ascending powers of t.

\n
[1]
\n
a.
\n
\n

By using the Maclaurin series for cosx and the result from part (a), show that the Maclaurin series for secx up to and including the term in x4 is 1+x22+5x424.

\n
[4]
\n
b.
\n
\n

By using the Maclaurin series for arctanx and the result from part (b), find limx0x arctan2xsecx-1.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

1-t+t2               A1

\n


Note: Accept 1, -t and t2.

\n

 

\n

[1 mark]

\n
a.
\n
\n

secx=11-x22!+x44!- =1-x22!+x44!--1                (M1)

\n

t=cosx-1  or  secx=1-cosx-1+cosx-12               (M1)

\n

=1--x22!+x44!-+-x22!+x44!-2               A1

\n

=1+x22-x424+x44               A1

\n

so the Maclaurin series for secx up to and including the term in x4 is 1+x22+5x424               AG

\n


Note:
Condone the absence of ‘…’ 

\n

 

\n

[4 marks]

\n
b.
\n
\n

arctan2x=2x-2x33+

\n

limx0x arctan2xsecx-1=limx0x2x-2x33+1+x22+5x424-1                      M1

\n

=limx02x2-8x43+x22+5x424              A1

\n

=limx02x21-4x23x221+5x212

\n

=4              A1

\n

 

\n

Note: Condone missing ‘lim’ and errors in higher derivatives.
Do not award M1 unless x is replaced by 2x in arctan.

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21M.2.AHL.TZ2.9", "topics": [ "topic-1-number-and-algebra", "topic-5-calculus" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices", "ahl-5-19-maclaurin-series", "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

AC is a vertical communications tower with its base at C.

\n

The tower has an observation deck, D, three quarters of the way to the top of the tower, A.

\n

\"N16/5/MATSD/SP1/ENG/TZ0/11\"

\n

From a point B, on horizontal ground 250 m from C, the angle of elevation of D is 48°.

\n
\n

Calculate CD, the height of the observation deck above the ground.

\n
[2]
\n
a.
\n
\n

Calculate the angle of depression from A to B.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

tan 48 = CD 250    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into the tangent ratio.

\n

 

\n

( CD = )   278   ( m )   ( 277.653 )    (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

tan ABC (or equivalent) = 4 3 × 277.653 250      (M1)(M1)(M1)

\n

 

\n

Note:     Award (M1) for 4 3 multiplying their part (a), (M1) for substitution into the tangent ratio, (M1) for correct substitution.

\n

 

\n

OR

\n

90 tan 1 ( 250 4 3 × 277.653 )    (M1)(M1)(M1)

\n

 

\n

Note:     Award (M1) for 4 3 multiplying their part (a), (M1) for substitution into the tangent ratio, (M1) for subtracting from 90 and for correct substitution.

\n

 

\n

(angle of depression = 56.0   ( 55.9687 )    (A1)(ft)     (C4)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Adam is a beekeeper who collected data about monthly honey production in his bee hives. The data for six of his hives is shown in the following table.

\n

\"N17/5/MATME/SP2/ENG/TZ0/08\"

\n

The relationship between the variables is modelled by the regression line with equation \nP\n=\na\nN\n+\nb\n.

\n
\n

Adam has 200 hives in total. He collects data on the monthly honey production of all the hives. This data is shown in the following cumulative frequency graph.

\n

\"N17/5/MATME/SP2/ENG/TZ0/08.c.d.e\"

\n

Adam’s hives are labelled as low, regular or high production, as defined in the following table.

\n

\"N17/5/MATME/SP2/ENG/TZ0/08.c.d.e_02\"

\n
\n

Adam knows that 128 of his hives have a regular production.

\n
\n

Write down the value of \na\n and of \nb\n.

\n
[3]
\n
a.
\n
\n

Use this regression line to estimate the monthly honey production from a hive that has 270 bees.

\n
[2]
\n
b.
\n
\n

Write down the number of low production hives.

\n
[1]
\n
c.
\n
\n

Find the value of \nk\n;

\n
[3]
\n
d.i.
\n
\n

Find the number of hives that have a high production.

\n
[2]
\n
d.ii.
\n
\n

Adam decides to increase the number of bees in each low production hive. Research suggests that there is a probability of 0.75 that a low production hive becomes a regular production hive. Calculate the probability that 30 low production hives become regular production hives.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of setup     (M1)

\n

eg\n\n\n\n\n\ncorrect value for \na\n or \nb\n

\n

\na\n=\n6.96103\n,\n\n \n\nb\n=\n\n454.805\n

\n

\na\n=\n6.96\n,\n\n \n\nb\n=\n\n455\n\n (accept \n\n6.96\nx\n\n455\n)\n     A1A1     N3

\n

[3 marks]

\n
a.
\n
\n

substituting \nN\n=\n270\n into their equation     (M1)

\n

eg\n\n\n\n\n\n\n6.96\n(\n270\n)\n\n455\n

\n

1424.67

\n

\nP\n=\n1420\n\n (g)\n\n     A1     N2

\n

[2 marks]

\n
b.
\n
\n

40 (hives)     A1     N1

\n

[1 mark]

\n
c.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n128\n+\n40\n

\n

168 hives have a production less than \nk\n     (A1)

\n

\nk\n=\n1640\n     A1     N3

\n

[3 marks]

\n
d.i.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n200\n\n168\n

\n

32 (hives)     A1     N2

\n

[2 marks]

\n
d.ii.
\n
\n

recognize binomial distribution (seen anywhere)     (M1)

\n

eg\n\n\n\n\n\n\nX\n\n\nB\n\n(\nn\n,\n\n \n\np\n)\n,\n\n \n\n\n(\n\n\n\n\nn\n\n\n\n\nr\n\n\n\n\n)\n\n\n\np\nr\n\n\n\n(\n1\n\np\n\n)\n\nn\n\nr\n\n\n\n

\n

correct values     (A1)

\n

eg\n\n\n\n\n\n\nn\n=\n40\n (check FT) and \np\n=\n0.75\n and \nr\n=\n30\n,\n\n \n\n\n(\n\n\n\n\n\n40\n\n\n\n\n\n\n30\n\n\n\n\n\n)\n\n\n\n0.75\n\n30\n\n\n\n\n(\n1\n\n0.75\n\n)\n\n10\n\n\n\n

\n

0.144364

\n

0.144     A1     N2

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "17N.2.SL.TZ0.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Two fixed points, A and B, are 40 m apart on horizontal ground. Two straight ropes, AP and BP, are attached to the same point, P, on the base of a hot air balloon which is vertically above the line AB. The length of BP is 30 m and angle BAP is 48°.

\n

\n
\n

Angle APB is acute.

\n
\n

On the diagram, draw and label with an x the angle of depression of B from P.

\n
[1]
\n
a.
\n
\n

Find the size of angle APB.

\n
[3]
\n
b.
\n
\n

Find the size of the angle of depression of B from P.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

(A1) (C1)

\n

[1 mark]

\n
a.
\n
\n

\n\n\n40\n\n\n\nsin APB\n\n\n\n=\n\n\n30\n\n\n\n\nsin 48\n\n\n\n\n\n     (M1)(A1)

\n

Note: Award (M1) for substitution into sine rule, (A1) for correct substitution.

\n

(angle APB =) 82.2°  (82.2473…°)     (A1)  (C3)

\n

[3 marks]

\n
b.
\n
\n

180 − 48 − 82.2473…     (M1)

\n

49.8°  (49.7526…°)     (A1)(ft)  (C2)

\n

Note: Follow through from parts (a) and (b).

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ1.T_8", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

SpeedWay airline flies from city \n\nA\n\n to city \n\nB\n\n. The flight time is normally distributed with a mean of \n260\n minutes and a standard deviation of \n15\n minutes.

\n

A flight is considered late if it takes longer than \n275\n minutes.

\n
\n

The flight is considered to be on time if it takes between \nm\n and \n275\n minutes. The probability that a flight is on time is \n0.830\n.

\n
\n

During a week, SpeedWay has \n12\n flights from city \n\nA\n\n to city \n\nB\n\n. The time taken for any flight is independent of the time taken by any other flight.

\n
\n

Calculate the probability a flight is not late.

\n
[2]
\n
a.
\n
\n

Find the value of m .

\n
[3]
\n
b.
\n
\n

Calculate the probability that at least 7 of these flights are on time.

\n
[3]
\n
c.i.
\n
\n

Given that at least 7 of these flights are on time, find the probability that exactly 10 flights are on time.

\n
[4]
\n
c.ii.
\n
\n

SpeedWay increases the number of flights from city A to city B to 20 flights each week, and improves their efficiency so that more flights are on time. The probability that at least 19 flights are on time is 0.788 .

\n

A flight is chosen at random. Calculate the probability that it is on time.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

valid approach       (M1)

\n

eg      P ( X < 275 ) ,   1 0.158655

\n

0.841344

\n

0.841        A1   N2

\n

[2 marks]

\n
a.
\n
\n

valid approach       (M1)

\n

eg      P ( X < 275 ) P ( X < m ) = 0.830

\n

correct working       (A1)

\n

eg       P ( X < m ) = 0.0113447

\n

225.820

\n

226 (minutes)      A1   N3

\n

[3 marks]

\n
b.
\n
\n

evidence of recognizing binomial distribution (seen anywhere)      (M1)

\n

eg      n C a × p a × q n a ,   B ( n p )

\n

evidence of summing probabilities from 7 to 12        (M1)

\n

eg       P ( X = 7 ) + P ( X = 8 ) + + P ( X = 12 ) 1 P ( X 6 )

\n

0.991248

\n

0.991       A1   N2

\n

[3 marks]

\n
c.i.
\n
\n

finding  P ( X = 10 )  (seen anywhere)       A1

\n

eg      ( 12 10 ) × 0.83 10 × 0.17 2 ( = 0.295952 )

\n

recognizing conditional probability      (M1)

\n

eg       P ( A | B ) ,   P ( X = 10 | X 7 ) ,   P ( X = 10 X 7 ) P ( X 7 )

\n

correct working      (A1)

\n

eg       0.295952 0.991248

\n

0.298565

\n

0.299       A1   N1

\n

Note: Exception to the FT rule: if the candidate uses an incorrect value for the probability that a flight is on time in (i) and working shown, award full FT in (ii) as appropriate.

\n

[4 marks]

\n
c.ii.
\n
\n

correct equation        (A1)

\n

eg       ( 20 19 ) p 19 ( 1 p ) + p 20 = 0.788

\n

valid attempt to solve     (M1)

\n

eg      graph

\n

0.956961

\n

0.957       A1   N1

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "19N.2.SL.TZ0.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The flight times, T minutes, between two cities can be modelled by a normal distribution with a mean of 75 minutes and a standard deviation of σ minutes.

\n
\n

On a particular day, there are 64 flights scheduled between these two cities.

\n
\n

Given that 2% of the flight times are longer than 82 minutes, find the value of σ.

\n
[3]
\n
a.
\n
\n

Find the probability that a randomly selected flight will have a flight time of more than 80 minutes.

\n
[2]
\n
b.
\n
\n

Given that a flight between the two cities takes longer than 80 minutes, find the probability that it takes less than 82 minutes.

\n
[4]
\n
c.
\n
\n

Find the expected number of flights that will have a flight time of more than 80 minutes.

\n
[3]
\n
d.
\n
\n

Find the probability that more than 6 of the flights on this particular day will have a flight time of more than 80 minutes.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

use of inverse normal to find z-score                   (M1)

\n

z=2.0537

\n

2.0537=82-75σ                  (A1)

\n

σ=3.408401

\n

σ=3.41                    A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

evidence of identifying the correct area under the normal curve               (M1)

\n

PT>80=0.071193

\n

PT>80=0.0712                   A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

recognition that P80<T<82 is required              (M1)

\n

PT<82T>80=P80<T<82PT>80=0.0511930.071193              (M1)(A1)

\n

=0.719075

\n

=0.719                   A1

\n

 

\n

[4 marks]

\n
c.
\n
\n

recognition of binomial probability             (M1)

\n

X~B64,0.071193  or  EX=64×0.071193              (A1)

\n

EX=4.556353

\n

EX=4.56   (flights)                  A1

\n

 

\n

[3 marks]

\n
d.
\n
\n

PX>6=PX7=1-PX6             (M1)

\n

=1-0.83088             (A1)

\n

=0.1691196

\n

=0.169                A1

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21M.2.SL.TZ2.8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations", "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

University students were surveyed and asked how many hours, \nh\n , they worked each month. The results are shown in the following table.

\n

\n
\n

Use the table to find the following values.

\n
\n

The first five class intervals, indicated in the table, have been used to draw part of a cumulative frequency curve as shown.

\n

\n
\n

\np\n.

\n
[1]
\n
a.i.
\n
\n

\nq\n.

\n
[1]
\n
a.ii.
\n
\n

On the same grid, complete the cumulative frequency curve for these data.

\n
[2]
\n
b.
\n
\n

Use the cumulative frequency curve to find an estimate for the number of students who worked at most 35 hours per month.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

\np\n=\n10\n     (A1)   (C1)  

\n

Note: Award (A1) for each correct value.

\n

[1 mark]

\n
a.i.
\n
\n

\nq\n=\n56\n     (A1)   (C1)  

\n

Note: Award (A1) for each correct value.

\n

[1 mark]

\n
a.ii.
\n
\n

   (A1)(A1)   (C2)  

\n

Note: Award (A1)(ft) for their 3 correctly plotted points; award (A1)(ft) for completing diagram with a smooth curve through their points. The second (A1)(ft) can follow through from incorrect points, provided the gradient of the curve is never negative. Award (C2) for a completely correct smooth curve that goes through the correct points.

\n

[2 marks]

\n
b.
\n
\n

a straight vertical line drawn at 35 (accept 35 ± 1)    (M1)

\n

26 (students)      (A1)   (C2)  

\n

Note: Accept values between 25 and 27 inclusive.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ2.T_12", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

Contestants in a TV gameshow try to get through three walls by passing through doors without falling into a trap. Contestants choose doors at random.
If they avoid a trap they progress to the next wall.
If a contestant falls into a trap they exit the game before the next contestant plays.
Contestants are not allowed to watch each other attempt the game.

\n

\n

The first wall has four doors with a trap behind one door.

\n

Ayako is a contestant.

\n
\n

Natsuko is the second contestant.

\n
\n

The second wall has five doors with a trap behind two of the doors.

\n

The third wall has six doors with a trap behind three of the doors.

\n

The following diagram shows the branches of a probability tree diagram for a contestant in the game.

\n

\n
\n

Write down the probability that Ayako avoids the trap in this wall.

\n
[1]
\n
a.
\n
\n

Find the probability that only one of Ayako and Natsuko falls into a trap while attempting to pass through a door in the first wall.

\n
[3]
\n
b.
\n
\n

Copy the probability tree diagram and write down the relevant probabilities along the branches.

\n
[3]
\n
c.
\n
\n

A contestant is chosen at random. Find the probability that this contestant fell into a trap while attempting to pass through a door in the second wall.

\n
[2]
\n
d.i.
\n
\n

A contestant is chosen at random. Find the probability that this contestant fell into a trap.

\n
[3]
\n
d.ii.
\n
\n

120 contestants attempted this game.

\n

Find the expected number of contestants who fell into a trap while attempting to pass through a door in the third wall.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n3\n4\n\n  (0.75, 75%)     (A1)

\n

[1 mark]

\n
a.
\n
\n

\n\n3\n4\n\n×\n\n1\n4\n\n+\n\n1\n4\n\n×\n\n3\n4\n\n  OR  \n2\n×\n\n3\n4\n\n×\n\n1\n4\n\n     (M1)(M1)

\n

Note: Award (M1) for their product \n\n1\n4\n\n×\n\n3\n4\n\n seen, and (M1) for adding their two products or multiplying their product by 2.

\n

\n=\n\n3\n8\n\n\n\n\n\n\n(\n\n\n6\n\n16\n\n\n,\n\n\n0.375\n,\n\n\n37.5\n\n\n\n\n)\n\n     (A1)(ft) (G3)

\n

Note: Follow through from part (a), but only if the sum of their two fractions is 1.

\n

[3 marks]

\n
b.
\n
\n

(A1)(ft)(A1)(A1)

\n

Note: Award (A1) for each correct pair of branches. Follow through from part (a).

\n

[3 marks]

\n
c.
\n
\n

\n\n3\n4\n\n×\n\n2\n5\n\n     (M1)

\n

Note: Award (M1) for correct probabilities multiplied together.

\n

\n=\n\n3\n\n10\n\n\n\n\n\n\n(\n\n0.3\n,\n\n\n30\n\n\n\n\n)\n\n     (A1)(ft) (G2)

\n

Note: Follow through from their tree diagram or part (a).

\n

[2 marks]

\n
d.i.
\n
\n

\n1\n\n\n3\n4\n\n×\n\n2\n5\n\n×\n\n3\n6\n\n  OR  \n\n1\n4\n\n+\n\n3\n4\n\n×\n\n2\n5\n\n+\n\n3\n4\n\n×\n\n3\n5\n\n×\n\n3\n6\n\n     (M1)(M1)

\n

Note: Award (M1) for \n\n3\n4\n\n×\n\n3\n5\n\n×\n\n3\n6\n\n and (M1) for subtracting their correct probability from 1, or adding to their \n\n1\n4\n\n+\n\n3\n4\n\n×\n\n2\n5\n\n.

\n

\n=\n\n\n93\n\n\n120\n\n\n\n\n\n\n\n(\n\n\n\n31\n\n\n40\n\n\n,\n\n\n0.775\n,\n\n\n77.5\n\n\n\n\n)\n\n     (A1)(ft) (G2)

\n

Note: Follow through from their tree diagram.

\n

[3 marks]

\n
d.ii.
\n
\n

\n\n3\n4\n\n×\n\n3\n5\n\n×\n\n3\n6\n\n×\n120\n      (M1)(M1)

\n

Note: Award (M1) for \n\n3\n4\n\n×\n\n3\n5\n\n×\n\n3\n6\n\n\n\n\n\n\n(\n\n\n3\n4\n\n×\n\n3\n5\n\n×\n\n3\n6\n\n\n\n\nOR\n\n\n\n\n\n27\n\n\n120\n\n\n\n\n\nOR\n\n\n\n\n9\n\n40\n\n\n\n)\n\n and (M1) for multiplying by 120.

\n

= 27      (A1)(ft) (G3)

\n

Note: Follow through from their tree diagram or their \n\n3\n4\n\n×\n\n3\n5\n\n×\n\n3\n6\n\n from their calculation in part (d)(ii).

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.2.SL.TZ1.T_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A function f is defined by fx=kex21+ex, where x, x0 and k+.

\n

The region enclosed by the graph of y=f(x), the x-axis, the y-axis and the line x=ln16 is rotated 360° about the x-axis to form a solid of revolution.

\n
\n

Pedro wants to make a small bowl with a volume of 300cm3 based on the result from part (a). Pedro’s design is shown in the following diagrams.

\n

\n

The vertical height of the bowl, BO, is measured along the x-axis. The radius of the bowl’s top is OA and the radius of the bowl’s base is BC. All lengths are measured in cm.

\n
\n

For design purposes, Pedro investigates how the cross-sectional radius of the bowl changes.

\n
\n

Show that the volume of the solid formed is 15k2π34 cubic units.

\n
[6]
\n
a.
\n
\n

Find the value of k that satisfies the requirements of Pedro’s design.

\n
[2]
\n
b.
\n
\n

Find OA.

\n
[2]
\n
c.i.
\n
\n

Find BC.

\n
[2]
\n
c.ii.
\n
\n

By sketching the graph of a suitable derivative of f, find where the cross-sectional radius of the bowl is decreasing most rapidly.

\n
[4]
\n
d.i.
\n
\n

State the cross-sectional radius of the bowl at this point.

\n
[2]
\n
d.ii.
\n
", "Markscheme": "
\n

attempt to use V=πabfx2dx                 (M1)

\n

V=π0ln16kex21+ex2dx  V=k2π0ln16ex1+ex2dx

\n


EITHER

\n

applying integration by recognition                 (M1)

\n

=k2π-11+ex0ln16           A3

\n


OR

\n

u=1+exdu=exdx            (A1)

\n

attempt to express the integral in terms of u             (M1)

\n

when x=0, u=2 and when x=ln16, u=17

\n

V=k2π2171u2du            (A1)

\n

=k2π-1u217             A1

\n

 

\n

OR

\n

u=exdu=exdx            (A1)

\n

attempt to express the integral in terms of u             (M1)

\n

when x=0, u=1 and when x=ln16, u=16

\n

V=k2π11611+u2du             (A1)

\n

=k2π-11+u116           A1

\n


Note: Accept equivalent working with indefinite integrals and original limits for x.

\n

 

\n

THEN

\n

=k2π12-117           A1

\n

so the volume of the solid formed is 15k2π34 cubic units           AG

\n


Note:
Award (M1)(A0)(M0)(A0)(A0)(A1) when 1534 is obtained from GDC

\n

 

\n

[6 marks]

\n
a.
\n
\n

a valid algebraic or graphical attempt to find k              (M1)

\n

k2=300×3415π

\n

k=14.7  =2170π=680π  (as k+)           A1

\n


Note: Candidates may use their GDC numerical solve feature.

\n

 

\n

[2 marks]

\n
b.
\n
\n

attempting to find OA=f0=k2

\n

with k=14.712 =2170π=680π             (M1)

\n

OA=7.36 =170π           A1

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

attempting to find BC=fln16=4k17

\n

with k=14.712 =2170π=680π             (M1)

\n

BC=3.46 =817170π=81017π           A1

\n

 

\n

[2 marks]

\n
c.ii.
\n
\n

EITHER

\n

recognising to graph y=f'x             (M1)

\n

Note: Award M1 for attempting to use quotient rule or product rule differentiation. f'x=kex21-ex21+ex2

\n


for x>0 graph decreasing to the local minimum           A1

\n

before increasing towards the x-axis           A1

\n

 

\n

OR

\n

recognising to graph y=f''x             (M1)

\n

Note: Award M1 for attempting to use quotient rule or product rule differentiation. f''x=kex2e2x-6ex+141+ex3

\n

for x>0, graph increasing towards and beyond the x-intercept          A1

\n

recognising f''x=0 for maximum rate          (A1)

\n

 

\n

THEN

\n

x=1.76  =ln22+3         A1

\n

 

\n

Note: Only award A marks if either graph is seen.

\n

[4 marks]

\n
d.i.
\n
\n

attempting to find f1.76             (M1)

\n

the cross-sectional radius at this point is 5.20 85πcm            A1

\n

 

\n

[2 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "21M.2.AHL.TZ2.11", "topics": [ "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution", "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

Pablo drives to work. The probability that he leaves home before 07:00 is \n\n3\n4\n\n.

\n

If he leaves home before 07:00 the probability he will be late for work is \n\n1\n8\n\n.

\n

If he leaves home at 07:00 or later the probability he will be late for work is \n\n5\n8\n\n.

\n
\n

Copy and complete the following tree diagram.

\n

\n
[3]
\n
a.
\n
\n

Find the probability that Pablo leaves home before 07:00 and is late for work.

\n
[2]
\n
b.
\n
\n

Find the probability that Pablo is late for work.

\n
[3]
\n
c.
\n
\n

Given that Pablo is late for work, find the probability that he left home before 07:00.

\n
[3]
\n
d.
\n
\n

Two days next week Pablo will drive to work. Find the probability that he will be late at least once.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

A1A1A1 N3

\n

Note: Award A1 for each bold fraction.

\n

[3 marks]

\n
a.
\n
\n

multiplying along correct branches      (A1)
eg   3 4 × 1 8

\n

P(leaves before 07:00 ∩ late) =  3 32     A1 N2

\n

[2 marks]

\n
b.
\n
\n

 

\n

multiplying along other “late” branch      (M1)
eg   1 4 × 5 8

\n

adding probabilities of two mutually exclusive late paths      (A1)
eg   ( 3 4 × 1 8 ) + ( 1 4 × 5 8 ) , 3 32 + 5 32

\n

P ( L ) = 8 32 ( = 1 4 )     A1 N2

\n

[3 marks]

\n
c.
\n
\n

recognizing conditional probability (seen anywhere)      (M1)
eg  P ( A | B ) , P ( before 7 | late )

\n

correct substitution of their values into formula      (A1)
eg  3 32 1 4

\n

P ( left before 07:00 | late ) = 3 8     A1 N2

\n

[3 marks]

\n
d.
\n
\n

valid approach      (M1)
eg  1 − P(not late twice), P(late once) + P(late twice)

\n

correct working      (A1)
eg   1 ( 3 4 × 3 4 ) , 2 × 1 4 × 3 4 + 1 4 × 1 4

\n

7 16     A1 N2

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.1.SL.TZ2.S_8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The quadrilateral ABCD represents a park, where \n\nAB\n\n=\n120\n\n m\n\n, \n\nAD\n\n=\n95\n\n m\n\n and \n\nDC\n\n=\n100\n\n m\n\n. Angle DAB is 70° and angle DCB is 110°. This information is shown in the following diagram.

\n

\"M17/5/MATSD/SP2/ENG/TZ2/04\"

\n

A straight path through the park joins the points B and D.

\n
\n

A new path, CE, is to be built such that E is the point on BD closest to C.

\n
\n

The section of the park represented by triangle DCE will be used for a charity race. A track will be marked along the sides of this section.

\n
\n

Find the length of the path BD.

\n
[3]
\n
a.
\n
\n

Show that angle DBC is 48.7°, correct to three significant figures.

\n
[3]
\n
b.
\n
\n

Find the area of the park.

\n
[4]
\n
c.
\n
\n

Find the length of the path CE.

\n
[2]
\n
d.
\n
\n

Calculate the total length of the track.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n(\n\nB\n\n\n\n\nD\n\n2\n\n\n=\n)\n\n \n\n\n\n95\n2\n\n\n+\n\n\n120\n2\n\n\n\n2\n×\n95\n×\n120\n×\ncos\n\n\n70\n\n\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substituted cosine rule, (A1) for correct substitution.

\n

 

\n

\n(\n\nBD\n\n=\n)\n\n \n\n125\n\n (m) \n\n\n(\n\n125.007\n\n\n (m)\n\n\n)\n\n     (A1)(G2)

\n

 

\n

[3 marks]

\n
a.
\n
\n

\n\n\nsin\n\n\nDBC\n\n\n\n100\n\n\n=\n\n\nsin\n\n\n110\n\n\n\n\n125.007\n\n\n\n     (M1)(A1)(ft)

\n

 

\n

Note:     Award (M1) for substituted sine rule, (A1)(ft) for correct substitution.

\n

Follow through from their answer to part (a).

\n

 

\n

\n(\n\nDBC\n\n=\n)\n\n \n\n48.7384\n\n\n\n\n     (A1)(ft)

\n

\n(\n\nDBC\n\n=\n)\n\n \n\n\n48.7\n\n\n     (AG)

\n

 

\n

Notes:     Award the final (A1)(ft) only if both their unrounded answer and 48.7° is seen. Follow through from their answer to part (a), only if their unrounded answer rounds to 48.7°.

\n

 

\n

[3 marks]

\n
b.
\n
\n

\n\n1\n2\n\n×\n125.007\n\n×\n100\n×\nsin\n\n\n21.3\n\n\n+\n\n1\n2\n\n×\n95\n×\n120\n×\nsin\n\n\n70\n\n\n     (A1)(M1)(M1)

\n

 

\n

Note:     Award (A1) for 21.3° (21.2615…) seen, (M1) for substitution into (at least) one area of triangle formula in the form \n\n1\n2\n\na\nb\nsin\n\nc\n, (M1) for their correct substitutions and adding the two areas.

\n

 

\n

\n7630\n\n \n\n\n\n\nm\n\n2\n\n\n\n \n\n(\n7626.70\n\n\n\n\nm\n\n2\n\n\n)\n     (A1)(ft)(G3)

\n

 

\n

Notes:     Follow through from their answers to part (a). Accept \n7620\n\n \n\n\n\n\nm\n\n2\n\n\n\n \n\n(\n7622.79\n\n\n\n\nm\n\n2\n\n\n)\n from use of 48.7384…

\n

 

\n

[4 marks]

\n
c.
\n
\n

\n(\n\nCE\n\n=\n)\n\n \n\n100\n×\nsin\n\n\n21.3\n\n\n     (M1)

\n

\n(\n\nCE\n\n=\n)\n\n \n\n36.3\n\n (m) \n\n\n(\n\n36.3251\n\n\n (m)\n\n\n)\n\n     (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from their angle 21.3° in part (c). Award (M0)(A0) for halving 110° and/or assuming E is the midpoint of BD in any method seen.

\n

 

\n

OR

\n

\n\narea of BCD\n\n=\n\n1\n2\n\n\nBD\n\n×\n\nCE\n\n     (M1)

\n

\n(\n\nCE\n\n=\n)\n\n \n\n36.3\n\n (m) \n\n\n(\n\n36.3251\n\n\n (m)\n\n\n)\n\n     (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from parts (a) and (c). Award (M0)(A0) for halving 110° and/or assuming E is the midpoint of BD in any method seen.

\n

 

\n

[2 marks]

\n
d.
\n
\n

\n\n\n\n\n100\n\n2\n\n\n\n36.3251\n\n\n\n2\n\n\n\n+\n100\n+\n36.3251\n\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for correct use of Pythagoras to find DE (or correct trigonometric equation, \n100\n×\ncos\n\n21.3\n, to find DE), (M1) for the sum of 100, their DE and their CE.

\n

 

\n

\n229\n\n (m) \n\n\n(\n\n229.494\n\n\n (m)\n\n\n)\n\n     (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from part (d). Use of 3 sf values gives an answer of \n230\n\n (m) \n\n\n(\n\n229.5\n\n (m)\n\n\n)\n\n.

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "17M.2.SL.TZ2.T_4", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

All answers in this question should be given to four significant figures.

\n


In a local weekly lottery, tickets cost $2 each.

\n

In the first week of the lottery, a player will receive $D for each ticket, with the probability distribution shown in the following table. For example, the probability of a player receiving $10 is 0.03. The grand prize in the first week of the lottery is $1000.

\n

\n
\n

If nobody wins the grand prize in the first week, the probabilities will remain the same, but the value of the grand prize will be $2000 in the second week, and the value of the grand prize will continue to double each week until it is won. All other prize amounts will remain the same.

\n
\n

Find the value of c.

\n
[2]
\n
a.
\n
\n

Determine whether this lottery is a fair game in the first week. Justify your answer.

\n
[4]
\n
b.
\n
\n

Given that the grand prize is not won and the grand prize continues to double, write an expression in terms of n for the value of the grand prize in the nth week of the lottery.

\n
[2]
\n
c.
\n
\n

The wth week is the first week in which the player is expected to make a profit. Ryan knows that if he buys a lottery ticket in the wth week, his expected profit is $p.

\n

Find the value of p.

\n
[7]
\n
d.
\n
", "Markscheme": "
\n

considering that sum of probabilities is 1             (M1)

\n

0.85+c+0.03+0.002+0.0001=1

\n

0.1179               A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

valid attempt to find ED            (M1)

\n

ED=0×0.85+2×0.1179+10×0.03+50×0.002+1000×0.0001

\n

ED=0.7358            A1

\n

No, not a fair game             A1

\n

for a fair game, ED would be $2 OR players expected winnings are 1.264             R1

\n

 

\n

[4 marks]

\n
b.
\n
\n

recognition of GP with r=2            (M1)

\n

1000×2n-1  OR  5002n           A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

recognizing ED>2            (M1)

\n

correct expression for wth week (or nth week)            (A1)

\n

0×0.85+2×0.1179+10×0.03+50×0.002+1000×2w-1×0.0001

\n

correct inequality (accept equation)            (A1)

\n

0.6358+1000×2w-1×0.0001>2  OR  2n-1>13.642

\n

 

\n

EITHER

\n

n-1>3.76998  OR  w=4.76998            (A1)

\n


OR

\n

ED=1.4358 in week 4  or  ED=2.2358 in week 5            (A1)

\n


THEN

\n

w=5            A1

\n

expected profit per ticket =their ED-2            (M1)

\n

=0.2358            A1

\n

 

\n

[7 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21M.2.SL.TZ2.9", "topics": [ "topic-4-statistics-and-probability", "topic-1-number-and-algebra" ], "subtopics": [ "sl-4-7-discrete-random-variables", "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

A function f is defined by fx=arcsinx2-1x2+1, x.

\n
\n

A function g is defined by gx=arcsinx2-1x2+1, x, x0.

\n
\n

Show that f is an even function.

\n
[1]
\n
a.
\n
\n

By considering limits, show that the graph of y=f(x) has a horizontal asymptote and state its equation.

\n
[2]
\n
b.
\n
\n

Show that f'x=2xx2x2+1 for x, x0.

\n
[6]
\n
c.i.
\n
\n

By using the expression for f'x and the result x2=x, show that f is decreasing for x<0.

\n

 

\n
[3]
\n
c.ii.
\n
\n

Find an expression for g-1(x), justifying your answer.

\n
[5]
\n
d.
\n
\n

State the domain of g-1.

\n
[1]
\n
e.
\n
\n

Sketch the graph of y=g-1(x), clearly indicating any asymptotes with their equations and stating the values of any axes intercepts.

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

EITHER

\n

f-x=arcsin-x2-1-x2+1=arcsinx2-1x2+1=fx            R1

\n


OR

\n

a sketch graph of y=fx with line symmetry in the y-axis indicated            R1

\n


THEN

\n

so fx is an even function.            AG

\n

 

\n

[1 mark]

\n
a.
\n
\n

as x±,  fxarcsin1π2            A1

\n

so the horizontal asymptote is y=π2            A1 

\n

 

\n

[2 marks]

\n
b.
\n
\n

attempting to use the quotient rule to find ddxx2-1x2+1            M1

\n

ddxx2-1x2+1=2xx2+1-2xx2-1x2+12  =4xx2+12            A1

\n

attempting to use the chain rule to find ddxarcsinx2-1x2+1            M1

\n

let u=x2-1x2+1 and so y=arcsinu and dydu=11-u2

\n

f'x=11-x2-1x2+12×4xx2+12            M1

\n

=4xx2+12-x2-12×1x2+1            A1

\n

=4x4x2×1x2+1            A1

\n

=2xx2x2+1            AG

\n

 

\n

[6 marks]

\n
c.i.
\n
\n

f'x=2xxx2+1

\n


EITHER

\n

for x<0, x=-x            (A1)

\n

so f'x=-2xx2+1            A1

\n


OR

\n

x>0 and x2+1>0            A1

\n

2x<0, x<0            A1

\n


THEN

\n

f'x<0              R1

\n


Note:
Award R1 for stating that in f'x, the numerator is negative, and the denominator is positive.

\n


so f is decreasing for x<0            AG

\n


Note:
Do not accept a graphical solution

\n

 

\n

[3 marks]

\n
c.ii.
\n
\n

x=arcsiny2-1y2+1            M1

\n

sinx=y2-1y2+1y2sinx+sinx=y2-1            A1

\n

y2=1+sinx1-sinx            A1

\n

domain of g is x, x0 and so the range of g-1 must be y, y0

\n

hence the positive root is taken (or the negative root is rejected)              R1

\n


Note: The R1 is dependent on the above A1.

\n


so g-1x=1+sinx1-sinx            A1

\n


Note: The final A1 is not dependent on R1 mark.

\n

 

\n

[5 marks]

\n
d.
\n
\n

domain is -π2x<π2            A1

\n


Note: Accept correct alternative notations, for example, -π2, π2  or -π2, π2).
Accept [-1.57,1.57[  if correct to 3 s.f.

\n

 

\n

[1 mark]

\n
e.
\n
\n

          A1A1A1

\n

Note: A1 for correct domain and correct range and y-intercept at y=1
         A1 for asymptotic behaviour xπ2
         A1 for x=π2
         Coordinates are not required. 
         Do not accept x=1.57 or other inexact values.

\n

 

\n

[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "21M.2.AHL.TZ2.12", "topics": [ "topic-5-calculus", "topic-2-functions", "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-5-2-increasing-and-decreasing-functions", "sl-2-5-composite-functions-identity-finding-inverse", "ahl-3-9-reciprocal-trig-ratios-and-their-pythagorean-identities-inverse-circular-functions", "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection", "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

A group of 20 students travelled to a gymnastics tournament together. Their ages, in years, are given in the following table.

\n

\"N17/5/MATSD/SP1/ENG/TZ0/01\"

\n
\n

The lower quartile of the ages is 16 and the upper quartile is 18.5.

\n
\n

For the students in this group find the mean age;

\n
[2]
\n
a.i.
\n
\n

For the students in this group write down the median age.

\n
[1]
\n
a.ii.
\n
\n

Draw a box-and-whisker diagram, for these students’ ages, on the following grid.

\n

\"N17/5/MATSD/SP1/ENG/TZ0/01.b\"

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

\n\n\n14\n+\n2\n×\n15\n+\n7\n×\n16\n+\n17\n+\n4\n×\n18\n+\n19\n+\n20\n+\n3\n×\n22\n\n\n20\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitutions into mean formula.

\n

 

\n

\n(\n=\n)\n\n \n\n17.5\n     (A1)     (C2)

\n

[2 marks]

\n
a.i.
\n
\n

16.5     (A1)     (C1)

\n

[1 mark]

\n
a.ii.
\n
\n

\"N17/5/MATSD/SP1/ENG/TZ0/01.b/M\"     (A1)(A1)(A1)(ft)     (C3)

\n

 

\n

Note:     Award (A1) for correct endpoints, (A1) for correct quartiles, (A1)(ft) for their median. Follow through from part (a)(ii), but only if median is between 16 and 18.5. If a horizontal line goes through the box, award at most (A1)(A1)(A0). Award at most (A0)(A1)(A1) if a ruler has not been used.

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "17N.1.SL.TZ0.T_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

The following table shows the mean weight, y kg , of children who are x years old.

\n

\n

The relationship between the variables is modelled by the regression line with equation \ny\n=\na\nx\n+\nb\n.

\n
\n

Find the value of a and of b.

\n
[3]
\n
a.i.
\n
\n

Write down the correlation coefficient.

\n
[1]
\n
a.ii.
\n
\n

Use your equation to estimate the mean weight of a child that is 1.95 years old.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid approach      (M1)

\n

eg correct value for a or b (or for r seen in (ii))

\n

a = 1.91966  b = 7.97717

\n

a = 1.92,  b = 7.98      A1A1 N3

\n

[3 marks]

\n
a.i.
\n
\n

0.984674

\n

= 0.985      A1 N1

\n

[1 mark]

\n
a.ii.
\n
\n

correct substitution into their equation      (A1)
eg  1.92 × 1.95 + 7.98

\n

11.7205

\n

11.7 (kg)      A1 N2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18M.2.SL.TZ2.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Three airport runways intersect to form a triangle, ABC. The length of AB is 3.1 km, AC is 2.6 km, and BC is 2.4 km.

\n

\n

A company is hired to cut the grass that grows in triangle ABC, but they need to know the area.

\n
\n

Find the size, in degrees, of angle BÂC.

\n
[3]
\n
a.
\n
\n

Find the area, in km2, of triangle ABC.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n(\n\ncos\n\nA\n=\n\n)\n\n\n\n\n\n\n\n\n2.6\n\n2\n\n\n+\n\n\n\n3.1\n\n2\n\n\n\n\n\n\n2.4\n\n2\n\n\n\n\n2\n\n(\n\n2.6\n\n)\n\n\n(\n\n3.1\n\n)\n\n\n\n     (M1)(A1)

\n

Note: Award (M1) for substituted cosine rule formula, (A1) for correct substitutions.

\n

48.8° (48.8381…°)       (A1)  (C3)

\n

[3 marks]

\n
a.
\n
\n

\n\n1\n2\n\n×\n2.6\n×\n3.1\n×\n\nsin\n\n\n(\n\n48.8381\n\n\n\n\n\n)\n\n    (M1)(A1)(ft)

\n

Note: Award (M1) for substituted area of a triangle formula, (A1) for correct substitution.

\n

3.03 (km2)  (3.033997…(km2))   (A1)(ft)  (C3)

\n

Note: Follow through from part (a).

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.SL.TZ1.T_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A transportation company owns 30 buses. The distance that each bus has travelled since being purchased by the company is recorded. The cumulative frequency curve for these data is shown.

\n

\n
\n

It is known that 8 buses travelled more than m kilometres.

\n
\n

Find the number of buses that travelled a distance between 15000 and 20000 kilometres.

\n
[2]
\n
a.
\n
\n

Use the cumulative frequency curve to find the median distance.

\n
[2]
\n
b.i.
\n
\n

Use the cumulative frequency curve to find the lower quartile.

\n
[1]
\n
b.ii.
\n
\n

Use the cumulative frequency curve to find the upper quartile.

\n
[1]
\n
b.iii.
\n
\n

Hence write down the interquartile range.

\n
[1]
\n
c.
\n
\n

Write down the percentage of buses that travelled a distance greater than the upper quartile.

\n
[1]
\n
d.
\n
\n

Find the number of buses that travelled a distance less than or equal to 12 000 km.

\n
[1]
\n
e.
\n
\n

Find the value of m.

\n
[2]
\n
f.
\n
\n

The smallest distance travelled by one of the buses was 2500 km.
The longest distance travelled by one of the buses was 23 000 km.

\n

On graph paper, draw a box-and-whisker diagram for these data. Use a scale of 2 cm to represent 5000 km.

\n
[4]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

28 − 20     (A1)

\n

Note: Award (A1) for 28 and 20 seen.

\n

8     (A1)(G2)

\n

[2 marks]

\n
a.
\n
\n

13500     (G2)

\n

Note: Accept an answer in the range 13500 to 13750.

\n

[2 marks]

\n
b.i.
\n
\n

10000     (G1)

\n

Note: Accept an answer in the range 10000 to 10250.

\n

[1 mark]

\n
b.ii.
\n
\n

16000     (G1)

\n

Note: Accept an answer in the range 16000 to 16250.

\n

[1 mark]

\n
b.iii.
\n
\n

6000     (A1)(ft)

\n

Note: Follow through from their part (b)(ii) and (iii).

\n

[1 mark]

\n
c.
\n
\n

25%     (A1)

\n

[1 mark]

\n
d.
\n
\n

11     (G1)

\n

[1 mark]

\n
e.
\n
\n

30 − 8  OR  22     (M1)

\n

Note: Award (M1) for subtracting 30 − 8 or 22 seen.

\n

15750     (A1)(G2)

\n

Note: Accept 15750 ± 250.

\n

[2 marks]

\n
f.
\n
\n

(A1)(A1)(A1)(A1)

\n

Note: Award (A1) for correct label and scale; accept “distance” or “km” for label.

\n

(A1)(ft) for correct median,
(A1)(ft) for correct quartiles and box,
(A1) for endpoints at 2500 and 23 000 joined to box by straight lines.
Accept ±250 for the median, quartiles and endpoints.
Follow through from their part (b).
The final (A1) is not awarded if the line goes through the box.

\n

[4 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "18M.2.SL.TZ2.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots" ] }, { "Question": "
\n

This question asks you to explore the behaviour and some key features of the function fn(x)=xn(a-x)n , where a+ and n+.

\n

In parts (a) and (b), only consider the case where a=2.

\n

Consider f1(x)=x(2-x).

\n
\n

Consider fnx=xn2-xn, where n+, n>1.

\n
\n

Now consider fnx=xna-xn where a+ and n+, n>1.

\n
\n

By using the result from part (f) and considering the sign of fn'-1, show that the point 0,0 on the graph of y=fnx is

\n
\n

Sketch the graph of y=f1(x), stating the values of any axes intercepts and the coordinates of any local maximum or minimum points.

\n
[3]
\n
a.
\n
\n

Use your graphic display calculator to explore the graph of y=fn(x) for

\n

•   the odd values n=3 and n=5;

\n

•   the even values n=2 and n=4.

\n

Hence, copy and complete the following table.

\n

\n
[6]
\n
b.
\n
\n

Show that fn'x=nxn-1a-2xa-xn-1.

\n
[5]
\n
c.
\n
\n

State the three solutions to the equation fn'x=0.

\n
[2]
\n
d.
\n
\n

Show that the point a2, fna2 on the graph of y=fnx is always above the horizontal axis.

\n
[3]
\n
e.
\n
\n

Hence, or otherwise, show that fn'a4>0, for n+.

\n
[2]
\n
f.
\n
\n

a local minimum point for even values of n, where n>1 and a+.

\n
[3]
\n
g.i.
\n
\n

a point of inflexion with zero gradient for odd values of n, where n>1 and a+.

\n
[2]
\n
g.ii.
\n
\n

Consider the graph of y=xna-xn-k, where n+a+ and k.

\n

State the conditions on n and k such that the equation xna-xn=k has four solutions for x.

\n
[5]
\n
h.
\n
", "Markscheme": "
\n

\n

inverted parabola extended below the x-axis             A1

\n

x-axis intercept values x=0,2         A1


Note: Accept a graph passing through the origin as an indication of x=0.

\n

local maximum at 1,1                 A1

\n


Note: Coordinates must be stated to gain the final A1.
        Do not accept decimal approximations.

\n


[3 marks]

\n
a.
\n
\n

             A1A1A1A1A1A1

\n


Note:
Award A1 for each correct value.

\n

For a table not sufficiently or clearly labelled, assume that their values are in the same order as the table in the question paper and award marks accordingly.

\n


[6 marks]

\n
b.
\n
\n

METHOD 1

\n

attempts to use the product rule            (M1)

\n

fn'x=-nxna-xn-1+nxn-1a-xn            A1A1

\n


Note: Award A1 for a correct udvdx and A1 for a correct vdudx.

\n


EITHER

\n

attempts to factorise fn'x (involving at least one of nxn-1 or a-xn-1)           (M1)

\n

=nxn-1a-xn-1a-x-x            A1

\n


OR

\n

attempts to express fn'x as the difference of two products with each product containing at least one of nxn-1 or a-xn-1           (M1)

\n

=-xnxn-1a-xn-1+a-xnxn-1a-xn-1            A1

\n


THEN

\n

fn'x=nxn-1a-2xa-xn-1            AG

\n


Note: Award the final (M1)A1 for obtaining any of the following forms: 

\n

fn'x=nxna-xna-x-xxa-x;   fn'x=nxna-xnxa-xa-x-x;

\n

        fn'x=nxn-1a-xn-xa-xn-1;

\n

        fn'x=a-xn-1nxn-1a-xn-nxn

\n

 

\n

 

\n

METHOD 2

\n

fnx=xa-xn           (M1)

\n

=ax-x2n            A1

\n

attempts to use the chain rule           (M1)

\n

fn'x=na-2xax-x2n-1            A1A1

\n


Note:
Award A1 for na-2x and A1 for ax-x2n-1.

\n


fn'x=nxn-1a-2xa-xn-1            AG

\n

 

\n

[5 marks]

\n
c.
\n
\n

x=0, x=a2, x=a            A2

\n

Note: Award A1 for either two correct solutions or for obtaining x=0, x=-a, x=-a2
       
  Award A0 otherwise.

\n

 

\n

[2 marks]

\n
d.
\n
\n

attempts to find an expression for fna2             (M1)

\n

fna2=a2na-a2n

\n

=a2na2n  =a22n,=a2n2            A1

\n


EITHER

\n

since a+, a22n>0  (for n+, n>1 and so fna2>0)                R1

\n


Note: Accept any logically equivalent conditions/statements on a and n.
        Award R0 if any conditions/statements specified involving a, n or both are incorrect.

\n

 

\n

OR

\n

(since a+), a2 raised to an even power (2n) (or equivalent reasoning) is always positive (and so  fna2>0)                R1

\n


Note: The condition a+ is given in the question. Hence some candidates will assume a+ and not state it. In these instances, award R1 for a convincing argument.
        Accept any logically equivalent conditions/statements on on a and n.
        Award R0 if any conditions/statements specified involving an or both are incorrect.

\n


THEN

\n

so a2, fna2 is always above the horizontal axis            AG

\n


Note: Do not award (M1)A0R1.

\n

 

\n

[3 marks]

\n
e.
\n
\n

METHOD 1

\n

fn'a4=na4n-1a-a2a-a4n-1  =na4n-1a23a4n-1            A1

\n


EITHER

\n

na4n-1a23a4n-1>0 as a+ and n+                R1

\n


OR

\n

na4n-1,a-a2 and a-a4n-1 are all >0                R1

\n

 

\n

Note: Do not award A0R1.
        Accept equivalent reasoning on correct alternative expressions for fn'a4 and accept any logically equivalent conditions/statements on a and n.

\n

        Exceptions to the above are condone n>1 and condone n>0.

\n

        An alternative form for fn'a4 is 2n3n-1a42n-1.

\n


THEN

\n

hence fn'a4>0                 AG

\n

 

\n

METHOD 2

\n

fn0=0 and fna2>0            A1

\n

(since fn is continuous and there are no stationary points between x=0 and x=a2)

\n

the gradient (of the curve) must be positive between x=0 and x=a2                 R1

\n


Note: Do not award A0R1.

\n


hence fn'a4>0                 AG

\n

 

\n

[2 marks]

\n
f.
\n
\n

fn'-1=n-1n-1a+2a+1n-1

\n

for n even:

\n

n-1n-1=-n<0  (and a+2,a+1n-1 are both >0)                R1

\n

fn'-1<0            A1

\n

fn'0=0 and fn'a4>0  (seen anywhere)            A1

\n

 

\n

Note: Candidates can give arguments based on the sign of -1n-1 to obtain the R mark.
        For example, award R1 for the following:
        If n is even, then n-1 is odd and hence -1n-1<0 =-1.
        Do not award R0A1.
        The second A1 is independent of the other two marks.
        The A marks can be awarded for correct descriptions expressed in words.
        Candidates can state (0,0) as a point of zero gradient from part (d) or show, state or explain (words or diagram) that fn'0=0. The last mark can be awarded for a clearly labelled diagram showing changes in the sign of the gradient.
        The last A1 can be awarded for use of a specific case (e.g. n=2).

\n


hence (0,0) is a local minimum point            AG

\n

 

\n

[3 marks]

\n
g.i.
\n
\n

for n odd:

\n

n-1n-1=n<0, (and a+2,a+1n-1 are both >0)  so fn'-1>0               R1

\n


Note: Candidates can give arguments based on the sign of -1n-1 to obtain the R mark.
        For example, award R1 for the following:
        If n is odd, then n-1 is even and hence -1n-1>0 =1.

\n


fn'0=0 and fn'a4>0  (seen anywhere)            A1

\n


Note: The A1 is independent of the R1.
         Candidates can state 0,0 as a point of zero gradient from part (d) or show, state or explain (words or diagram) that fn'0=0. The last A mark can be awarded for a clearly labelled diagram showing changes in the sign of the gradient.
        The last A1 can be awarded for use of a specific case (e.g. n=3).

\n

 

\n

hence (0,0) is a point of inflexion with zero gradient           AG

\n

 

\n

[2 marks]

\n
g.ii.
\n
\n

considers the parity of n            (M1)

\n


Note: Award M1 for stating at least one specific even value of n.

\n


n must be even (for four solutions)           A1

\n


Note: The above 2 marks are independent of the 3 marks below.

\n

 

\n

0<k<a22n           A1A1A1

\n

 

\n

Note: Award A1 for the correct lower endpoint, A1 for the correct upper endpoint and A1 for strict inequality signs.

\n

         The third A1 (strict inequality signs) can only be awarded if A1A1 has been awarded.
         For example, award A1A1A0 for 0ka22n. Award A1A0A0 for k>0.

\n

         Award A1A0A0 for 0<k<fna2.

\n

 

\n

[5 marks]

\n
h.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.i.
\n
\n[N/A]\n
g.ii.
\n
\n[N/A]\n
h.
\n
", "question_id": "21M.3.AHL.TZ2.1", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-3-graphing", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "sl-5-2-increasing-and-decreasing-functions" ] }, { "Question": "
\n

The maximum temperature \nT\n, in degrees Celsius, in a park on six randomly selected days is shown in the following table. The table also shows the number of visitors, \nN\n, to the park on each of those six days.

\n

\"M17/5/MATME/SP2/ENG/TZ2/02\"

\n

The relationship between the variables can be modelled by the regression equation \nN\n=\na\nT\n+\nb\n.

\n
\n

Find the value of \na\n and of \nb\n.

\n
[3]
\n
a.i.
\n
\n

Write down the value of  \nr\n.

\n
[1]
\n
a.ii.
\n
\n

Use the regression equation to estimate the number of visitors on a day when the maximum temperature is 15 °C.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

evidence of set up     (M1)

\n

eg\n\n\n\n\n\ncorrect value for \na\n or \nb\n

\n

0.667315, 22.2117

\n

\na\n=\n0.667\n,\n\n \n\nb\n=\n22.2\n     A1A1     N3

\n

[3 marks]

\n
a.i.
\n
\n

0.922958

\n

\nr\n=\n0.923\n     A1     N1

\n

[1 marks]

\n
a.ii.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n0.667\n(\n15\n)\n+\n22.2\n,\n\n \n\nN\n(\n15\n)\n

\n

32.2214     (A1)

\n

32 (visitors) (must be an integer)     A1     N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.2.SL.TZ2.S_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A farmer owns a plot of land in the shape of a quadrilateral ABCD.

\n

\n\nAB\n\n=\n105\n\n m, BC\n\n=\n95\n\n m, CD\n\n=\n40\n\n m, DA\n\n=\n70\n\n m\n\n and angle \n\nDCB\n\n=\n\n90\n\n\n.

\n

\"N16/5/MATSD/SP2/ENG/TZ0/05\"

\n

The farmer wants to divide the land into two equal areas. He builds a fence in a straight line from point B to point P on AD, so that the area of PAB is equal to the area of PBCD.

\n

Calculate

\n
\n

the length of BD;

\n
[2]
\n
a.
\n
\n

the size of angle DAB;

\n
[3]
\n
b.
\n
\n

the area of triangle ABD;

\n
[3]
\n
c.
\n
\n

the area of quadrilateral ABCD;

\n
[2]
\n
d.
\n
\n

the length of AP;

\n
[3]
\n
e.
\n
\n

the length of the fence, BP.

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n(\n\nBD\n\n=\n)\n\n \n\n\n\n\n\n95\n\n2\n\n\n+\n\n\n\n40\n\n2\n\n\n\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into Pythagoras’ theorem.

\n

 

\n

\n=\n103\n\n \n\n(\n\nm\n\n)\n\n \n\n\n(\n\n103.077\n\n,\n\n \n\n25\n\n17\n\n\n)\n\n    (A1)(G2)

\n

[2 marks]

\n
a.
\n
\n

\ncos\n\n\n\nB\n\n\nA\n^\n\n\nD\n\n\n=\n\n\n\n\n\n105\n\n2\n\n\n+\n\n\n\n70\n\n2\n\n\n\n\n\n\n(\n103.077\n\n)\n\n2\n\n\n\n\n2\n×\n105\n×\n70\n\n\n     (M1)(A1)(ft)

\n

 

\n

Note:     Award (M1) for substitution into cosine rule, (A1)(ft) for their correct substitutions. Follow through from part (a).

\n

 

\n

\n(\n\n\nB\n\n\nA\n^\n\n\nD\n\n\n)\n=\n\n68.9\n\n\n\n \n\n(\n68.8663\n\n)\n    (A1)(ft)(G2)

\n

 

\n

Note:     If their 103 used, the answer is \n68.7995\n\n

\n

 

\n

[3 marks]

\n
b.
\n
\n

\n(\n\nArea of ABD\n\n=\n)\n\n1\n2\n\n×\n105\n×\n70\n×\nsin\n\n(\n68.8663\n\n)\n    (M1)(A1)(ft)

\n

 

\n

Notes:     Award (M1) for substitution into the trig form of the area of a triangle formula.

\n

Award (A1)(ft) for their correct substitutions.

\n

Follow through from part (b).

\n

If 68.8° is used the area \n=\n3426.28\n\n\n \n\n\n\n\nm\n\n2\n\n\n.

\n

 

\n

\n=\n3430\n\n \n\n\n\n\nm\n\n2\n\n\n\n \n\n(\n3427.82\n\n)\n    (A1)(ft)(G2)

\n

[3 marks]

\n
c.
\n
\n

\n\narea of ABCD\n\n=\n\n1\n2\n\n×\n40\n×\n95\n+\n3427.82\n\n    (M1)

\n

 

\n

Note:     Award (M1) for correctly substituted area of triangle formula added to their answer to part (c).

\n

 

\n

\n=\n5330\n\n \n\n\n\n\nm\n\n2\n\n\n\n \n\n(\n5327.83\n\n)\n    (A1)(ft)(G2)

\n

[2 marks]

\n
d.
\n
\n

\n\n1\n2\n\n×\n105\n×\n\nAP\n\n×\nsin\n\n(\n68.8663\n\n)\n=\n0.5\n×\n5327.82\n\n    (M1)(M1)

\n

 

\n

Notes:     Award (M1) for the correct substitution into triangle formula.

\n

Award (M1) for equating their triangle area to half their part (d).

\n

 

\n

\n(\n\nAP\n\n=\n)\n\n \n\n54.4\n\n \n\n(\n\nm\n\n)\n\n \n\n(\n54.4000\n\n)\n    (A1)(ft)(G2)

\n

 

\n

Notes:     Follow through from parts (b) and (d).

\n

 

\n

[3 marks]

\n
e.
\n
\n

\n\nB\n\n\n\n\nP\n\n2\n\n\n=\n\n\n105\n2\n\n\n+\n\n(\n54.4000\n\n\n)\n2\n\n\n\n2\n×\n105\n×\n(\n54.4000\n\n)\n×\ncos\n\n(\n68.8663\n\n)\n    (M1)(A1)(ft)

\n

 

\n

Notes:     Award (M1) for substituted cosine rule formula.

\n

Award (A1)(ft) for their correct substitutions. Accept the exact fraction \n\n\n53\n\n\n147\n\n\n in place of \ncos\n\n(\n68.8663\n\n)\n.

\n

Follow through from parts (b) and (e).

\n

 

\n

\n(\n\nBP\n\n=\n)\n\n \n\n99.3\n\n \n\n(\n\nm\n\n)\n\n \n\n(\n99.3252\n\n)\n    (A1)(ft)(G2)

\n

 

\n

Notes:     If 54.4 and \ncos\n\n(\n68.9\n)\n are used the answer is \n99.3567\n\n

\n

 

\n

[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "16N.2.SL.TZ0.T_5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Jim heated a liquid until it boiled. He measured the temperature of the liquid as it cooled. The following table shows its temperature, \nd\n degrees Celsius, \nt\n minutes after it boiled.

\n

\"M17/5/MATME/SP1/ENG/TZ1/04\"

\n
\n

Jim believes that the relationship between \nd\n and \nt\n can be modelled by a linear regression equation.

\n
\n

Write down the independent variable.

\n
[1]
\n
a.i.
\n
\n

Write down the boiling temperature of the liquid.

\n
[1]
\n
a.ii.
\n
\n

Jim describes the correlation as very strong. Circle the value below which best represents the correlation coefficient.

\n

\n0.992\n\n\n\n0.251\n\n\n\n0\n\n\n\n\n0.251\n\n\n\n\n0.992\n

\n
[2]
\n
b.
\n
\n

Jim’s model is \nd\n=\n\n2.24\nt\n+\n105\n, for \n0\n\nt\n\n20\n. Use his model to predict the decrease in temperature for any 2 minute interval.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

\nt\n     A1     N1

\n

[1 mark]

\n
a.i.
\n
\n

105     A1     N1

\n

[1 mark]

\n
a.ii.
\n
\n

\n\n0.992\n     A2     N2

\n

[2 marks]

\n
b.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\n\n\nd\n\nd\n\n\n\nd\n\nt\n\n\n=\n\n2.24\n;\n\n \n\n2\n×\n2.24\n,\n\n \n\n2\n×\n\n2.24\n,\n\n \n\nd\n(\n2\n)\n=\n\n2\n×\n2.24\n×\n105\n,\n

\n

finding \nd\n(\n\n\nt\n2\n\n\n)\n\nd\n(\n\n\nt\n1\n\n\n)\n where \n\n\nt\n2\n\n\n=\n\n\nt\n1\n\n\n+\n2\n

\n

4.48 (degrees)     A1     N2

\n

 

\n

Notes:     Award no marks for answers that directly use the table to find the decrease in temperature for 2 minutes eg \n\n\n105\n\n98.4\n\n2\n\n=\n3.3\n.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ1.S_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

The function f is defined by fx=2x+43-x, where x, x3.

\n
\n

Write down the equation of

\n
\n

Find the coordinates where the graph of f crosses

\n
\n

the vertical asymptote of the graph of f.

\n
[1]
\n
a.i.
\n
\n

the horizontal asymptote of the graph of f.

\n
[1]
\n
a.ii.
\n
\n

the x-axis.

\n
[1]
\n
b.i.
\n
\n

the y-axis.

\n
[1]
\n
b.ii.
\n
\n

Sketch the graph of f on the axes below.

\n

\n
[1]
\n
c.
\n
", "Markscheme": "
\n

x=3                 A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

y=-2                 A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

-2,0   (accept x=-2)                 A1

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

0,43   (accept y=43 and f0=43)                 A1

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

               A1

\n


Note:
Award A1 for completely correct shape: two branches in correct quadrants with asymptotic behaviour.

\n

 

\n

[1 mark]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "21N.1.SL.TZ0.3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-8-reciprocal-and-simple-rational-functions-equations-of-asymptotes" ] }, { "Question": "
\n

Use l’Hôpital’s rule to determine the value of

\n

limx02sinx-sin2xx3.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

using l’Hôpital’s rule,

\n

limx02sinx-sin2xx3=limx02cosx-2cos2x3x2        M1A1

\n

=limx0-2sinx+4sin2x6x       (M1)A1

\n

=limx0-2cosx+8cos2x6       A1

\n

=1       A1

\n


[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.1.AHL.TZ0.F_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Assuming the Maclaurin series for cosx and ln(1+x), show that the Maclaurin series for cos(ln(1+x)) is

\n

1-12x2+12x3-512x4+

\n
[4]
\n
a.
\n
\n

By differentiating the series in part (a), show that the Maclaurin series for sin(ln(1+x)) is x-12x2+16x3+ .

\n
[4]
\n
b.
\n
\n

Hence determine the Maclaurin series for tan(ln(1+x)) as far as the term in x3.

\n
[5]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

METHOD 1 

\n

attempts to substitute lnx+1=x-12x2+13x3-14x4+ into

\n

cosx=1-12x2+124x4-        M1

\n

cosx=ln1+x=1-12x-12x2+13x3+2+124x+4+        A1

\n

attempts to expand the RHS up to and including the x4 term        M1

\n

=1-12x2-x3+14x4+23x4+124x4+        A1

\n

=1-12x2+12x3-512x4+        AG

\n

 

\n

METHOD 2

\n

attempts to substitute lnx+1 into cosx=1-12x2+124x4-        M1

\n

cosln1+x=1-12ln1+x2+124ln1+x4-

\n

attempts to find the Maclaurin series for ln1+x2 up to and including the x4 term        M1

\n

ln1+x2=x2-x3+1112x4-        A1

\n

ln1+x2=x4-

\n

=1-12x2-x3+1112x4++124x4+        A1

\n

=1-12x2+12x3-512x4+        AG

\n


[4 marks]

\n
a.
\n
\n

-sin(ln(1+x))×11+x=-x+32x2-53x3+        A1A1

\n

sin(ln(1+x))=-1+x-x+32x2-53x3+

\n

attempts to expand the RHS up to and including the x3 term         M1

\n

=x-32x2+53x3+x2-32x3+        A1

\n

=x-12x2+16x3+        AG

\n


[4 marks]

\n
b.
\n
\n

METHOD 1

\n

let tan(ln(1+x))=a0+a1x+a2x2+a3x3+

\n

uses sin(ln(1+x))=cos(ln(1+x))×tan(ln(1+x)) to form         M1

\n

x-12x2+16x3+=1-12x2+12x3+a0+a1x+a2x2+a3x3+        A1

\n

=a0+a1x+a2-12a0x2+a3-12a1+12a0x3+         (A1)

\n

attempts to equate coefficients,

\n

a0=0,  a1=1,  a2-12a0=-12,  a3-12a1+12a0=16         M1

\n

a0=0,  a1=1,  a2=-12,  a3=23        A1

\n

so tan(ln(1+x)) =x-12x2+23x3+

\n

 

\n

METHOD 2

\n

uses tan(ln(1+x))=sin(ln(1+x))cos(ln(1+x)) to form         M1

\n

=x-12x2+16x3+1-12x2+12x3+-1        A1

\n

=1-12x2+12x3+-1=1+12x2-12x3+         (A1)

\n

attempts to expand the RHS up to and including the x3 term         M1

\n

=x-12x2+16x3+1+12x2-12x3+

\n

=x+12x3-12x2+16x3+

\n

=x-12x2+23x3+        A1

\n


Note: Accept use of long division.

\n


[5 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.2.AHL.TZ0.F_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-19-maclaurin-series" ] }, { "Question": "
\n

Box 1 contains 5 red balls and 2 white balls.

\n

Box 2 contains 4 red balls and 3 white balls.

\n
\n

A box is chosen at random and a ball is drawn. Find the probability that the ball is red.

\n
[3]
\n
a.
\n
\n

Let A be the event that “box 1 is chosen” and let R be the event that “a red ball is drawn”.

\n

Determine whether events A and R are independent.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid approach to find PR                 (M1)

\n

tree diagram (must include probabilty of picking box) with correct required probabilities

\n

OR   PRB1+PRB2   OR   PRB1PB1+PRB2PB2

\n

57·12+47·12                 (A1)

\n

PR=914                A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

events A and R are not independent, since 914·12514  OR  57914  OR  5912

\n

OR an explanation e.g. different number of red balls in each box                A2

\n

 

\n

Note: Both conclusion and reasoning are required. Do not split the A2.

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.1.SL.TZ0.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The curve y=f(x) has a gradient function given by

\n

dydx=x-y.

\n

The curve passes through the point (1, 1).

\n
\n

On the same set of axes, sketch and label isoclines for dydx=-1, 0 and 1, and clearly indicate the value of each y-intercept.

\n
[3]
\n
a.i.
\n
\n

Hence or otherwise, explain why the point (1, 1) is a local minimum.

\n
[3]
\n
a.ii.
\n
\n

Find the solution of the differential equation dydx=x-y, which passes through the point (1, 1). Give your answer in the form y=f(x).

\n
[8]
\n
b.
\n
\n

Explain why the graph of y=fx does not intersect the isocline dydx=1.

\n
[2]
\n
c.i.
\n
\n

Sketch the graph of y=fx on the same set of axes as part (a)(i).

\n
[2]
\n
c.ii.
\n
", "Markscheme": "
\n

attempt to find equation of isoclines by setting x-y=-1,0,1       M1

\n

\n

3 parallel lines with positive gradient       A1

\n

y-intercept =-c for dydx=c       A1

\n


Note: To award A1, each y-intercept should be clear, but condone a missing label (eg. (0, 0)).

\n

If candidates represent the lines using slope fields, but omit the lines, award maximum of M1A0A1.

\n


[3 marks]

\n
a.i.
\n
\n

at point 1, 1, dydx=0      A1

\n


EITHER

\n

to the left of (1, 1), the gradient is negative       R1

\n

to the right of (1, 1), the gradient is positive        R1

\n


Note: Accept any correct reasoning using gradient, isoclines or slope field.

\n

If a candidate uses left/right or x<1/x>1  without explicitly referring to the point (1, 1) or a correct region on the diagram, award R0R1.

\n


OR

\n

d2ydx2=1-dydx       A1

\n

d2ydx2=1>0       A1

\n


Note:
accept correct reasoning dydx that is increasing as x increases.

\n


THEN

\n

hence (1, 1) is a local minimum       AG

\n


[3 marks]

\n
a.ii.
\n
\n

integrating factor =edx       (M1)

\n

=ex       (A1)

\n

dydxex+yex=xex       (M1)

\n

yex=xex dx      A1

\n

=xex-ex dx       (M1)

\n

=xex-ex+c      A1

\n


Note: Award A1 for the correct RHS.

\n


substituting (1, 1) gives

\n

e=e-e+c      M1

\n

c=e

\n

y=x-1+e1-x      A1

\n


[8 marks]

\n
b.
\n
\n

METHOD 1

\n

EITHER

\n

attempt to solve for the intersection x-1+e1-x=x-1       (M1)

\n


OR

\n

attempt to find the difference x-1+e1-x-x-1      (M1)

\n


THEN

\n

e1-x>0 for all x       R1

\n


Note: Accept e1-x0 or equivalent reasoning.

\n


therefore the curve does not intersect the isocline       AG

\n

 

\n

METHOD 2

\n

y=x-1 is an (oblique) asymptote to the curve       R1

\n


Note: Do not accept “the curve is parallel to y=x-1\"

\n


y=x-1 is the isocline for dydx=1       R1

\n

therefore the curve does not intersect the isocline       AG

\n

 

\n

METHOD 3

\n

The initial point is above y=x-1, so dydx<1       R1

\n

x-y<1

\n

y>x-1       R1

\n

therefore the curve does not intersect the isocline       AG

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

 

\n

\n

concave up curve with minimum at approximately 1, 1       A1

\n

asymptote of curve is isocline y=x-1       A1

\n


Note: Only award FT from (b) if the above conditions are satisfied.

\n


[2 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "20N.3.AHL.TZ0.HCA_3", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

A triangular postage stamp, ABC, is shown in the diagram below, such that \n\nAB\n\n=\n5\n\n cm\n\n,\n\n\nB\n\n\nA\n^\n\n\nC\n\n\n=\n\n34\n\n\n,\n\n\nA\n\n\nB\n^\n\n\nC\n\n\n=\n\n26\n\n\n and \n\n\nA\n\n\nC\n^\n\n\nB\n\n\n=\n\n120\n\n\n.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/13\"

\n
\n

Find the length of BC.

\n
[3]
\n
a.
\n
\n

Find the area of the postage stamp.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\n\n\nBC\n\n\n\nsin\n\n\n34\n\n\n\n\n=\n\n5\n\nsin\n\n\n120\n\n\n\n\n     (M1)(A1)

\n

 

\n

Note:     Award (M1) for substituted sine rule formula, (A1) for correct substitutions.

\n

 

\n

\n\nBC\n\n=\n3.23\n\n (cm) \n\n\n(\n\n3.22850\n\n\n (cm)\n\n\n)\n\n     (A1)     (C3)

\n

[3 marks]

\n
a.
\n
\n

\n\n1\n2\n\n(\n5\n)\n(\n3.22850\n)\nsin\n\n\n26\n\n\n     (M1)(A1)(ft)

\n

 

\n

Note:     Award (M1) for substituted area of a triangle formula, (A1) for correct substitutions.

\n

 

\n

\n=\n3.54\n\n \n\n(\n\nc\n\n\n\n\nm\n\n2\n\n\n)\n\n \n\n\n(\n\n3.53820\n\n\n \n\n(\n\nc\n\n\n\n\nm\n\n2\n\n\n)\n\n)\n\n     (A1)(ft)     (C3)

\n

 

\n

Note:     Follow through from part (a).

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ1.T_13", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The following table shows the hand lengths and the heights of five athletes on a sports team.

\n

\n

The relationship between x and y can be modelled by the regression line with equation y = ax + b.

\n
\n

Find the value of a and of b.

\n
[3]
\n
a.i.
\n
\n

Write down the correlation coefficient.

\n
[1]
\n
a.ii.
\n
\n

Another athlete on this sports team has a hand length of 21.5 cm. Use the regression equation to estimate the height of this athlete.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

evidence of set up      (M1)

\n

eg   correct value for a or b or r (seen in (ii)) or r2 (= 0.973)

\n

9.91044,   −31.3194

\n

a = 9.91,   b = −31.3,   y = 9.91x − 31.3      A1A1 N3

\n

 

\n

[3 marks]

\n
a.i.
\n
\n

0.986417

\n

r = 0.986        A1 N1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

substituting x = 21.5 into their equation       (M1)

\n

eg    9.91(21.5) − 31.3

\n

181.755

\n

182 (cm)       A1 N2

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "18N.2.SL.TZ0.S_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

This question asks you to investigate and prove a geometric property involving the roots of the equation zn=1 where z for integers n, where n2.

\n


The roots of the equation zn=1 where z are 1, ω, ω2, , ωn-1, where ω=e2πin. Each root can be represented by a point P0, P1, P2, , Pn-1, respectively, on an Argand diagram.

\n

For example, the roots of the equation z2=1 where z are 1 and ω. On an Argand diagram, the root 1 can be represented by a point P0 and the root ω can be represented by a point P1.

\n

Consider the case where n=3.

\n

The roots of the equation z3=1 where z are 1, ω and ω2. On the following Argand diagram, the points P0, P1 and P2 lie on a circle of radius 1 unit with centre O(0, 0).

\n

\n
\n

Line segments [P0P1] and [P0P2] are added to the Argand diagram in part (a) and are shown on the following Argand diagram.

\n

\n

P0P1is the length of [P0P1] and P0P2 is the length of [P0P2].

\n
\n

Consider the case where n=4.

\n

The roots of the equation z4=1 where z are 1, ω, ω2 and ω3.

\n
\n

On the following Argand diagram, the points P0, P1, P2 and P3 lie on a circle of radius 1 unit with centre O(0, 0). [P0P1], [P0P2] and [P0P3] are line segments.

\n

\n
\n

For the case where n=5, the equation z5=1 where z has roots 1, ω, ω2, ω3 and ω4.

\n

It can be shown that P0P1×P0P2×P0P3×P0P4=5.

\n

Now consider the general case for integer values of n, where n2.

\n

The roots of the equation zn=1 where z are 1, ω, ω2, , ωn-1. On an Argand diagram, these roots can be represented by the points P0, P1, P2, , Pn-1 respectively where [P0P1], [P0P2], , [P0Pn-1] are line segments. The roots lie on a circle of radius 1 unit with centre O(0, 0).

\n
\n

P0P1 can be expressed as |1-ω|.

\n
\n

Consider zn-1=(z-1)(zn-1+zn-2+  +z+1) where z.

\n
\n

Show that (ω-1)(ω2+ω+1)=ω3-1.

\n
[2]
\n
a.i.
\n
\n

Hence, deduce that ω2+ω+1=0.

\n
[2]
\n
a.ii.
\n
\n

Show that P0P1×P0P2=3.

\n
[3]
\n
b.
\n
\n

By factorizing z4-1, or otherwise, deduce that ω3+ω2+ω+1=0.

\n
[2]
\n
c.
\n
\n

Show that P0P1×P0P2×P0P3=4.

\n
[4]
\n
d.
\n
\n

Suggest a value for P0P1×P0P2×  ×P0Pn-1.

\n
[1]
\n
e.
\n
\n

Write down expressions for P0P2 and P0P3 in terms of ω.

\n
[2]
\n
f.i.
\n
\n

Hence, write down an expression for P0Pn-1 in terms of n and ω.

\n
[1]
\n
f.ii.
\n
\n

Express zn-1+ zn-2+  +z+1 as a product of linear factors over the set .

\n
[3]
\n
g.i.
\n
\n

Hence, using the part (g)(i) and part (f) results, or otherwise, prove your suggested result to part (e).

\n
[4]
\n
g.ii.
\n
", "Markscheme": "
\n

METHOD 1

\n

attempts to expand (ω-1)(ω2+ω+1)            (M1)

\n

=ω3+ω2+ω-ω2-ω-1           A1

\n

=ω3-1           AG

\n

 

\n

METHOD 2

\n

attempts polynomial division on ω3-1ω-1            M1

\n

=ω2+ω+1           A1

\n

so (ω-1)(ω2+ω+1)=ω3-1           AG

\n

 

\n

Note: In part (a), award marks as appropriate where ω has been converted into Cartesian, modulus-argument (polar) or Euler form.

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

(since ω is a root of z3=1)ω3-1=0           R1

\n

and ω1           R1

\n

ω2+ω+1=0           AG

\n

 

\n

Note: In part (a), award marks as appropriate where ω has been converted into Cartesian, modulus-argument (polar) or Euler form.

\n

  

\n

[2 marks]

\n
a.ii.
\n
\n

METHOD 1

\n

attempts to find either  P0P1 or P0P2             (M1)

\n

accept any valid method

\n

e.g.  2sinπ3,  12+12-2cos2π3,  1sinπ6=P0P1sin2π3from either ΔOP0P1 or ΔOP0P2

\n

e.g. use of Pythagoras’ theorem

\n

e.g. 1-ei2π3,  1--12+32i by calculating the distance between 2 points

\n

P0P1=3           A1

\n

P0P2=3           A1

\n


Note:
Award a maximum of M1A1A0 for any decimal approximation seen in the calculation of either P0P1 or P0P2 or both.

\n


so P0P1×P0P2=3            AG

\n

 

\n

METHOD 2

\n

attempts to find P0P1×P0P2=1-ω1-ω2             (M1)

\n

P0P1×P0P2=ω3-ω2-ω+1           A1

\n

=1-ω2+ω+1+2  and since ω2+ω+1=0           R1

\n

so P0P1×P0P2=3            AG

\n

 

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

z41=z1z3+z2+z+1           A1

\n

(ω is a root hence) ω4-1=0 and ω1           R1

\n

ω3+ω2+ω+1=0            AG

\n


Note: Condone the use of ω throughout.

\n

 

\n

METHOD 2

\n

considers the sum of roots of z4-1=0             (M1)

\n

the sum of roots is zero (there is no z3 term)         A1

\n

ω3+ω2+ω+1=0            AG

\n

 

\n

METHOD 3

\n

substitutes for ω             (M1)

\n

e.g. LHS=ei3π2+eπi+eiπ2+1

\n

=-i-1+i+1         A1

\n


Note: This can be demonstrated geometrically or by using vectors. Accept Cartesian or modulus-argument (polar) form.

ω3+ω2+ω+1=0            AG

\n

 

\n

METHOD 4

\n

ω3+ω2+ω+1=ω4-1ω-1         A1

\n

=0ω-1=0 as ω1           R1

\n

ω3+ω2+ω+1=0            AG

\n

 

\n

[2 marks]

\n
c.
\n
\n

METHOD 1

\n

P0P2=2           A1

\n

attempts to find either P0P1 or P0P3             (M1)

\n

 

\n

Note: For example P0P1=1-i and P0P3=1+i.
         Various geometric and trigonometric approaches can be used by candidates.

\n

 

\n

P0P1=2, P0P3=2           A1A1

\n


Note: Award a maximum of A1M1A1A0 if labels such as P0P1 are not clearly shown.
         Award full marks if the lengths are shown on a clearly labelled diagram.
         Award a maximum of A1M1A1A0 for any decimal approximation seen in the calculation of either P0P1 or P0P3 or both.

\n


P0P1×P0P2×P0P3=4            AG

\n

 

\n

METHOD 2

\n

attempts to find P0P1×P0P2×P0P3=1-ω1-ω21-ω3            M1

\n

P0P1×P0P2×P0P3=-ω6+ω5+ω4-ω2-ω+1         A1

\n

=--1+ω5+1--1-ω+1  since ω6=ω2=-1 and ω4=1        A1

\n

=ω5-ω+4 and since ω5=ω           R1

\n

so P0P1×P0P2×P0P3=4            AG

\n

 

\n

METHOD 3

\n

P0P2=2           A1

\n

attempts to find P0P1×P0P3=1-ω1-ω3            M1

\n

P0P1×P0P3=ω4-ω3-ω+1         A1

\n

=2--ω-ω  since ω4=1 and ω3=-ω               R1     

\n

so P0P1×P0P2×P0P3=4            AG

\n

 

\n

[4 marks]

\n
d.
\n
\n

P0P1×P0P2×  ×P0Pn-1=n         A1

\n

 

\n

[1 mark]

\n
e.
\n
\n

P0P2=1-ω2, P0P3=1-ω3         A1A1

\n

 

\n

[2 marks]

\n
f.i.
\n
\n

P0Pn-1=1-ωn-1         A1A1

\n

 
Note: Accept 1-ω from symmetry.

\n


[1 mark]

\n
f.ii.
\n
\n

zn-1=z-1zn-1+ zn-2+  +z+1

\n

considers the equation zn-1+ zn-2+  +z+1=0         (M1)

\n

the roots are ω, ω2,  , ωn-1         (A1)

\n

so z-ωz-ω2z-ωn-1         A1

\n


[3 marks]

\n
g.i.
\n
\n

METHOD 1

\n

substitutes z=1into z-ωz-ω2z-ωn-1zn-1+ zn-2+  +z+1           M1

\n

1-ω1-ω21-ωn-1=n         (A1)

\n

takes modulus of both sides           M1

\n

1-ω1-ω21-ωn-1=n

\n

1-ω1-ω21-ωn-1=n                 A1

\n

so P0P1×P0P2××P0Pn-1=n                 AG

\n

 

\n

Note: Award a maximum of M1A1FTM1A0 from part (e).

\n

 

\n

METHOD 2

\n

1-ω,1-ω2,,1-ωn-1 are the roots of 1-vn-1+1-vn-2++1-v+1=0           M1

\n

coefficient of vn-1 is -1n-1 and the coefficient of 1 is n                 A1

\n

product of the roots is -1n-1n-1n-1=n                 A1

\n

1-ω1-ω21-ωn-1=n                 A1

\n

so P0P1×P0P2××P0Pn-1=n                 AG

\n


[4 marks]

\n
g.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
\n[N/A]\n
g.i.
\n
\n[N/A]\n
g.ii.
\n
", "question_id": "21M.3.AHL.TZ2.2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

Consider the differential equation dydx=y-xy+x, where x, y>0.

\n

It is given that y=2 when x=1.

\n
\n

Solve the differential equation, giving your answer in the form fx,y=0.

\n
[9]
\n
a.
\n
\n

The graph of y against x has a local maximum between x=2 and x=3. Determine the coordinates of this local maximum.

\n
[4]
\n
b.
\n
\n

Show that there are no points of inflexion on the graph of y against x.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

puts y=vx so that dydx=v+xdvdx               M1

\n

v+xdvdx=vx-xvx+x =v-1v+1            A1

\n

attempts to express xdvdx as a single rational fraction in v

\n

xdvdx=-v2+1v+1               M1

\n

attempts to separate variables               M1

\n

v+1v2+1dv=-1xdx

\n

12lnv2+1+arctanv=-lnx+C            A1A1

\n

substitutes y=2,x=1 and attempts to find the value of C               M1

\n

C=12ln5+arctan2            A1

\n

the solution is

\n

12lny2x2+1+arctanyx+lnx-12ln5-arctan2=0            A1

\n


[9 marks]

\n
a.
\n
\n

at a maximum, dydx=0               M1

\n

attempts to substitute y=x into their solution               M1

\n

12ln2+arctan1+lnx=12ln5+arctan2

\n

attempts to solve for x,y               (M1)

\n

2.18,2.18  102earctan2-π4,102earctan2-π4              A1

\n


Note:
Accept all answers that round to the correct 2sf answer.
Accept x=2.18,y=2.18.

\n


[4 marks]

\n
b.
\n
\n

METHOD 1

\n

attempts (quotient rule) implicit differentiation               M1

\n

d2ydx2=dydx-1y+x-y-xdydx+1y+x2

\n

correctly substitutes dydx=y-xy+x into d2ydx2

\n

=y-xy+x-1y+x-y-xy-xy+x+1y+x2              A1

\n

=-2x2+y2x+y3              A1

\n

this expression can never be zero therefore no points of inflexion              R1

\n

 

\n

METHOD 2

\n

attempts implicit differentiation on y+xdydx=y-x               M1

\n

dydx+1dydx+y+xd2ydx2=dydx-1              A1

\n

y+xd2ydx2=dydx-1-dydx2-dydx

\n

=-1-dydx2              A1

\n

-1-dydx2<0 and x+y>0, d2ydx20 therefore no points of inflexion              R1

\n


Note:
Accept putting d2ydx2=0 and obtaining contradiction.

\n


[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.2.AHL.TZ0.F_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx" ] }, { "Question": "
\n

A jigsaw puzzle consists of many differently shaped pieces that fit together to form a picture.

\n

\n

Jill is doing a 1000-piece jigsaw puzzle. She started by sorting the edge pieces from the interior pieces. Six times she stopped and counted how many of each type she had found. The following table indicates this information.

\n

\n

Jill models the relationship between these variables using the regression equation \ny\n=\na\nx\n+\nb\n.

\n
\n

Write down the value of \na\n and of \nb\n.

\n
[3]
\n
a.
\n
\n

Use the model to predict how many edge pieces she had found when she had sorted a total of 750 pieces.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)

\n

eg  correct value for \na\n or \nb\n (ignore incorrect labels)

\n

\na\n=\n6.92986\n,  \nb\n=\n8.80769\n

\n

\na\n=\n6.93\n,  \nb\n=\n8.81\n  (accept \ny\n=\n6.93\nx\n+\n8.81\n)   A1A1  N3

\n

[3 marks]

\n
a.
\n
\n

valid approach     (M1)

\n

eg  750 = \nx\n+\ny\n, edge + interior = 750

\n

correct working     (A1)

\n

eg  750 − \nx\n = 6.9298\nx\n + 8.807 , 93.4684

\n

93 (pieces) (accept 94)     A1  N3

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.2.SL.TZ1.S_5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

A restaurant serves desserts in glasses in the shape of a cone and in the shape of a hemisphere. The diameter of a cone shaped glass is 7.2 cm and the height of the cone is 11.8 cm as shown.

\n

\"N17/5/MATSD/SP2/ENG/TZ0/06\"

\n
\n

The volume of a hemisphere shaped glass is \n225\n\n c\n\n\n\n\nm\n\n3\n\n\n.

\n
\n

The restaurant offers two types of dessert.

\n

The regular dessert is a hemisphere shaped glass completely filled with chocolate mousse. The cost, to the restaurant, of the chocolate mousse for one regular dessert is $1.89.

\n
\n

The special dessert is a cone shaped glass filled with two ingredients. It is first filled with orange paste to half of its height and then with chocolate mousse for the remaining volume.

\n

\"N17/5/MATSD/SP2/ENG/TZ0/06.d.e.f\"

\n
\n

The cost, to the restaurant, of \n100\n\n c\n\n\n\n\nm\n\n3\n\n\n of orange paste is $7.42.

\n
\n

A chef at the restaurant prepares 50 desserts; \nx\n regular desserts and \ny\n special desserts. The cost of the ingredients for the 50 desserts is $111.44.

\n
\n

Show that the volume of a cone shaped glass is \n160\n\n c\n\n\n\n\nm\n\n3\n\n\n, correct to 3 significant figures.

\n
[2]
\n
a.
\n
\n

Calculate the radius, \nr\n, of a hemisphere shaped glass.

\n
[3]
\n
b.
\n
\n

Find the cost of \n100\n\n c\n\n\n\n\nm\n\n3\n\n\n of chocolate mousse.

\n
[2]
\n
c.
\n
\n

Show that there is \n20\n\n c\n\n\n\n\nm\n\n3\n\n\n of orange paste in each special dessert.

\n
[2]
\n
d.
\n
\n

Find the total cost of the ingredients of one special dessert.

\n
[2]
\n
e.
\n
\n

Find the value of \nx\n.

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n(\nV\n=\n)\n\n \n\n\n1\n3\n\nπ\n\n(\n3.6\n\n)\n2\n\n\n×\n11.8\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into volume of a cone formula.

\n

 

\n

\n=\n160.145\n\n\n \n\n(\n\nc\n\n\n\n\nm\n\n3\n\n\n)\n     (A1)

\n

\n=\n160\n\n \n\n(\n\nc\n\n\n\n\nm\n\n3\n\n\n)\n     (AG)

\n

 

\n

Note:     Both rounded and unrounded answers must be seen for the final (A1) to be awarded.

\n

 

\n

[2 marks]

\n
a.
\n
\n

\n\n1\n2\n\n×\n\n4\n3\n\nπ\n\n\nr\n3\n\n\n=\n225\n     (M1)(A1)

\n

 

\n

Notes:     Award (M1) for multiplying volume of sphere formula by \n\n1\n2\n\n (or equivalent).

\n

Award (A1) for equating the volume of hemisphere formula to 225.

\n

 

\n

OR

\n

\n\n4\n3\n\nπ\n\n\nr\n3\n\n\n=\n450\n     (A1)(M1)

\n

 

\n

Notes:     Award (A1) for 450 seen, (M1) for equating the volume of sphere formula to 450.

\n

 

\n

\n(\nr\n=\n)\n\n \n\n4.75\n\n \n\n(\n\ncm\n\n)\n\n \n\n(\n4.75380\n\n)\n     (A1)(G2)

\n

[3 marks]

\n
b.
\n
\n

\n\n\n1.89\n×\n100\n\n\n225\n\n\n     (M1)

\n

 

\n

Note:     Award (M1) for dividing 1.89 by 2.25, or equivalent.

\n

 

\n

\n=\n0.84\n     (A1)(G2)

\n

 

\n

Note: Accept 84 cents if the units are explicit.

\n

 

\n

[2 marks]

\n
c.
\n
\n

\n\n\nr\n2\n\n\n=\n1.8\n     (A1)

\n

\n\n\nV\n2\n\n\n=\n\n1\n3\n\nπ\n\n(\n1.8\n\n)\n2\n\n\n×\n5.9\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into volume of a cone formula, but only if the result rounds to 20.

\n

 

\n

\n=\n20\n\n c\n\n\n\n\nm\n\n3\n\n\n     (AG)

\n

OR

\n

\n\n\nr\n2\n\n\n=\n\n1\n2\n\nr\n     (A1)

\n

\n\n\nV\n2\n\n\n=\n\n\n\n(\n\n\n1\n2\n\n\n)\n\n3\n\n\n160\n     (M1)

\n

 

\n

Notes:     Award (M1) for multiplying 160 by \n\n\n\n(\n\n\n1\n2\n\n\n)\n\n3\n\n\n. Award (A0)(M1) for \n\n1\n8\n\n×\n160\n if \n\n1\n2\n\n is not seen.

\n

 

\n

\n=\n20\n\n \n\n(\n\nc\n\n\n\n\nm\n\n3\n\n\n)\n     (AG)

\n

 

\n

Notes:     Do not award any marks if the response substitutes in the known value \n(\nV\n=\n20\n)\n to find the radius of the cone.

\n

 

\n

[2 marks]

\n
d.
\n
\n

\n\n\n20\n\n\n100\n\n\n×\n7.42\n+\n\n\n140\n\n\n100\n\n\n×\n0.84\n     (M1)

\n

 

\n

Note:     Award (M1) for the sum of two correct products.

\n

 

\n

$ 2.66     (A1)(ft)(G2)

\n

 

\n

Note:     Follow through from part (c).

\n

 

\n

[2 marks]

\n
e.
\n
\n

\nx\n+\ny\n=\n50\n     (M1)

\n

 

\n

Note:     Award (M1) for correct equation.

\n

 

\n

\n1.89\nx\n+\n2.66\ny\n=\n111.44\n     (M1)

\n

 

\n

Note:     Award (M1) for setting up correct equation, including their 2.66 from part (e).

\n

 

\n

\n(\nx\n=\n)\n\n \n\n28\n     (A1)(ft)(G3)

\n

 

\n

Note:     Follow through from part (e), but only if their answer for \nx\n is rounded to the nearest positive integer, where \n0\n<\nx\n<\n50\n.

\n

Award at most (M1)(M1)(A0) for a final answer of “28, 22”, where the \nx\n-value is not clearly defined.

\n

 

\n

[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "17N.2.SL.TZ0.T_6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

The function f is defined by fx=ln1+x2 where -1<x<1.

\n
\n

The seventh derivative of f is given by f7x=1440xx6-21x4+35x2-71+x27.

\n
\n

Use the Maclaurin series for ln(1+x) to write down the first three non-zero terms of the Maclaurin series for f(x).

\n
[2]
\n
a.i.
\n
\n

Hence find the first three non-zero terms of the Maclaurin series for x1+x2.

\n
[4]
\n
a.ii.
\n
\n

Use your answer to part (a)(i) to write down an estimate for f0.4.

\n
[1]
\n
b.
\n
\n

Use the Lagrange form of the error term to find an upper bound for the absolute value of the error in calculating f(0.4), using the first three non-zero terms of the Maclaurin series for f(x).

\n
[6]
\n
c.i.
\n
\n

With reference to the Lagrange form of the error term, explain whether your answer to part (b) is an overestimate or an underestimate for f(0.4).

\n
[2]
\n
c.ii.
\n
", "Markscheme": "
\n

substitution of x2 in ln(1+x)=x-x22+x33-        (M1)

\n

x2-x42+x63       A1

\n


[2 marks]

\n
a.i.
\n
\n

ddxln1+x2=2x1+x2        (M1)

\n


Note: Award (M1) if this is seen in part (a)(i).

\n


attempt to differentiate their answer in part (a)        (M1)

\n


2x1+x2=2x-4x32+6x53       M1

\n


Note: Award M1 for equating their derivatives.

\n


x1+x2=x-x3+x5       A1

\n


[4 marks]

\n
a.ii.
\n
\n

f0.40.149         A1

\n


Note: Accept an answer that rounds correct to 2 s.f. or better.

\n


[1 mark]

\n
b.
\n
\n

attempt to find the maximum of f7c for c0,0.4       (M1)

\n

maximum of f7c occurs at c=0.199       (A1)

\n

f7c<1232.97  (for all c]0,0.4[)       (A1)

\n

use of x=0.4       (M1)

\n

substitution of n=6 and a=0 and their value of x and their value of f7c into Lagrange error term       (M1)

\n


Note: Award (M1) for substitution of n=3 and a=0 and their value of x and their value of f4c into Lagrange error term.

\n


R60.4<1232.970.477!

\n

upper bound =0.000401         A1

\n


Note: Accept an answer that rounds correct to 1 s.f or better.

\n


[6 marks]

\n
c.i.
\n
\n

f7c<0  (for all c]0,0.4[)       R1

\n


Note: Accept R6c<0 or “the error term is negative”.

\n


the answer in (b) is an overestimate       A1

\n


Note: The A1 is dependent on the R1.

\n


[2 marks]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "20N.3.AHL.TZ0.HCA_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-19-maclaurin-series" ] }, { "Question": "
\n

A discrete random variable X has the probability distribution given by the following table.

\n

\n

Given that EX=1912, determine the value of p and the value of q.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

EX=0×p+1×14+2×16+3q=1912        (M1)

\n

14+13+3q=1912

\n

q=13        A1

\n

p+14+16+q=1        (M1)

\n

p+q=712

\n

p=14        A1

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.1.AHL.TZ0.H_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Consider the function fx=ax3+bx2+cx+d , where x and a, b, c, d

\n
\n

Consider the function gx=12x3-3x2+6x-8, where x.

\n
\n

The graph of y=g(x) may be obtained by transforming the graph of y=x3 using a sequence of three transformations.

\n
\n

Write down an expression for f'x.

\n
[1]
\n
a.i.
\n
\n

Hence, given that f1 does not exist, show that b23ac>0.

\n
[3]
\n
a.ii.
\n
\n

Show that g1 exists.

\n
[2]
\n
b.i.
\n
\n

g(x) can be written in the form p(x2)3+q , where p, q.

\n

Find the value of p and the value of q.

\n
[3]
\n
b.ii.
\n
\n

Hence find g-1(x).

\n
[3]
\n
b.iii.
\n
\n

State each of the transformations in the order in which they are applied.

\n
[3]
\n
c.
\n
\n

Sketch the graphs of y=g(x) and y=g-1(x) on the same set of axes, indicating the points where each graph crosses the coordinate axes.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

f'x=3ax2+2bx+c        A1

\n


[1 mark]

\n
a.i.
\n
\n

since f1 does not exist, there must be two turning points       R1

\n

(f'x=0 has more than one solution)

\n

using the discriminant Δ>0        M1

\n

4b2-12ac>0        A1

\n

b2-3ac>0        AG

\n


[4 marks]

\n
a.ii.
\n
\n

METHOD 1

\n

b2-3ac=-32-3×12×6        M1

\n

=9-9

\n

=0        A1

\n

hence g1 exists        AG

\n

 

\n

METHOD 2

\n

g'x=32x2-6x+6        M1

\n

Δ=-62-4×32×6

\n

Δ=36-36=0 there is (only) one point with gradient of 0 and this must be a point of inflexion (since gx is a cubic.)       R1

\n

hence g1 exists        AG

\n


[2 marks]

\n
b.i.
\n
\n

p=12         A1

\n

x-23=x3-6x2+12x-8          (M1)

\n

12x3-6x2+12x-8=12x3-3x2+6x-4

\n

gx=12x-23-4q=-4        A1

\n


[3 marks]

\n
b.ii.
\n
\n

x=12y-23-4          (M1)

\n


Note: Interchanging x and y can be done at any stage.

\n


2x+4=y-23          (M1)

\n

2x+43=y-2

\n

y=2x+43+2

\n

g-1x=2x+43+2        A1

\n


Note: g-1x= must be seen for the final A mark.

\n


[3 marks]

\n
b.iii.
\n
\n

translation through 20,          A1

\n


Note: This can be seen anywhere.

\n


EITHER
a stretch scale factor 12 parallel to the y-axis then a translation through 0-4          A2
OR
a translation through 0-8 then a stretch scale factor 12 parallel to the y-axis          A2

\n


Note:
Accept ‘shift’ for translation, but do not accept ‘move’. Accept ‘scaling’ for ‘stretch’.

\n


[3 marks]

\n
c.
\n
\n

        A1A1A1M1A1

\n


Note:
Award A1 for correct ‘shape’ of g (allow non-stationary point of inflexion)
Award A1 for each correct intercept of g
Award M1 for attempt to reflect their graph in y=x, A1 for completely correct g-1 including intercepts

\n


[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "20N.1.AHL.TZ0.H_10", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

A cylindrical container with a radius of 8 cm is placed on a flat surface. The container is filled with water to a height of 12 cm, as shown in the following diagram.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/12\"

\n
\n

A heavy ball with a radius of 2.9 cm is dropped into the container. As a result, the height of the water increases to \nh\n cm, as shown in the following diagram.

\n

\"M17/5/MATSD/SP1/ENG/TZ2/12.b\"

\n
\n

Find the volume of water in the container.

\n
[2]
\n
a.
\n
\n

Find the value of \nh\n.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nπ\n×\n\n\n8\n2\n\n\n×\n12\n     (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into the volume of a cylinder formula.

\n

 

\n

\n2410\n\n c\n\n\n\n\nm\n\n3\n\n\n\n \n\n(\n2412.74\n\n\n c\n\n\n\n\nm\n\n3\n\n\n,\n\n \n\n768\nπ\n\n c\n\n\n\n\nm\n\n3\n\n\n)\n     (A1)     (C2)

\n

[2 marks]

\n
a.
\n
\n

\n\n4\n3\n\nπ\n×\n\n\n2.9\n3\n\n\n+\n768\nπ\n=\nπ\n×\n\n\n8\n2\n\n\nh\n     (M1)(M1)(M1)

\n

 

\n

Note:     Award (M1) for correct substitution into the volume of a sphere formula (this may be implied by seeing 102.160…), (M1) for adding their volume of the ball to their part (a), (M1) for equating a volume to the volume of a cylinder with a height of \nh\n.

\n

 

\n

OR

\n

\n\n4\n3\n\nπ\n×\n\n\n2.9\n3\n\n\n=\nπ\n×\n\n\n8\n2\n\n\n(\nh\n\n12\n)\n     (M1)(M1)(M1)

\n

 

\n

Note:     Award (M1) for correct substitution into the volume of a sphere formula (this may be implied by seeing 102.160…), (M1) for equating to the volume of a cylinder, (M1) for the height of the water level increase, \nh\n\n12\n. Accept \nh\n for \nh\n\n12\n if adding 12 is implied by their answer.

\n

 

\n

\n(\nh\n=\n)\n\n \n\n12.5\n\n (cm) \n\n\n(\n\n12.5081\n\n\n (cm)\n\n\n)\n\n     (A1)(ft)     (C4)

\n

 

\n

Note:     If 3 sf answer used, answer is 12.5 (12.4944…). Follow through from part (a) if first method is used.

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ2.T_12", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Srinivasa places the nine labelled balls shown below into a box.

\n

\n

Srinivasa then chooses two balls at random, one at a time, from the box. The first ball is not replaced before he chooses the second.

\n
\n

Find the probability that the first ball chosen is labelled A.

\n
[1]
\n
a.i.
\n
\n

Find the probability that the first ball chosen is labelled A or labelled N.

\n
[1]
\n
a.ii.
\n
\n

Find the probability that the second ball chosen is labelled A, given that the first ball chosen was labelled N.

\n
[2]
\n
b.
\n
\n

Find the probability that both balls chosen are labelled N.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

39 13, 0.333, 0.333333, 33.3%        (A1)   (C1)

\n


[1 mark]

\n
a.i.
\n
\n

59 0.556, 0.555555, 55.6%        (A1)   (C1)

\n


[1 mark]

\n
a.ii.
\n
\n

38 0.375, 37.5%        (A1)(A1)   (C2)

\n


Note:
Award (A1) for correct numerator, (A1) for correct denominator.

\n


[2 marks]

\n
b.
\n
\n

29×18        (M1)

\n


Note:
Award (M1) for a correct compound probability calculation seen.

\n


272 136, 0.0278, 0.0277777, 2.78%       (A1)  (C2)

\n


[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.SL.TZ0.T_6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-5-probability-concepts-expected-numbers" ] }, { "Question": "
\n

A cylinder with radius \nr\n and height \nh\n is shown in the following diagram.

\n

\n

The sum of \nr\n and \nh\n for this cylinder is 12 cm.

\n
\n

Write down an equation for the area, \nA\n, of the curved surface in terms of \nr\n.

\n
[2]
\n
a.
\n
\n

Find \n\n\n\nd\n\nA\n\n\n\nd\n\nr\n\n\n.

\n
[2]
\n
b.
\n
\n

Find the value of \nr\n when the area of the curved surface is maximized.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\nA\n=\n2\nπ\nr\n\n(\n\n12\n\nr\n\n)\n\n  OR  \nA\n=\n24\nπ\nr\n\n2\nπ\n\n\nr\n2\n\n\n        (A1)(M1)  (C2)

\n

Note: Award (A1) for  \nr\n+\nh\n=\n12\n  or  \nh\n=\n12\n\nr\n  seen. Award (M1) for correctly substituting into curved surface area of a cylinder. Accept \nA\n=\n2\nπ\nr\n\n(\n\n12\n\nr\n\n)\n\n  OR  \nA\n=\n24\nπ\nr\n\n2\nπ\n\n\nr\n2\n\n\n.

\n

[2 marks]

\n
a.
\n
\n

\n24\nπ\n\n4\nπ\nr\n       (A1)(ft)(A1)(ft)  (C2)

\n

Note: Award (A1)(ft) for \n24\nπ\n and  (A1)(ft) for \n\n4\nπ\nr\n . Follow through from part (a). Award at most (A1)(ft)(A0) if additional terms are seen.

\n

[2 marks]

\n
b.
\n
\n

\n24\nπ\n\n4\nπ\nr\n=\n0\n       (M1)

\n

Note: Award (M1) for setting their part (b) equal to zero.

\n

6 (cm)       (A1)(ft)  (C2)

\n

Note: Follow through from part (b).

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ1.T_15", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Anne-Marie planted four sunflowers in order of height, from shortest to tallest.

\n

\n

Flower C is 32cm tall.

\n

The median height of the flowers is 24cm.

\n
\n

The range of the heights is 50cm. The height of Flower A is pcm and the height of Flower D is qcm.

\n
\n

The mean height of the flowers is 27cm.

\n
\n

Find the height of Flower null.

\n
[2]
\n
a.
\n
\n

Using this information, write down an equation in p and q.

\n
[1]
\n
b.
\n
\n

Write down a second equation in p and q.

\n
[1]
\n
c.
\n
\n

Using your answers to parts (b) and (c), find the height of Flower A.

\n
[1]
\n
d.i.
\n
\n

Using your answers to parts (b) and (c), find the height of Flower D.

\n
[1]
\n
d.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

24-8  OR  24-32-24  OR  24=32+h2        (M1)

\n


Note:
Award (M1) for subtracting 8 from the median, or equivalent.

\n


16 cm       (A1)  (C2)

\n


[2 marks]

\n
a.
\n
\n

q-p=50  (or equivalent)      (A1)  (C1)

\n


[1 mark]

\n
b.
\n
\n

p+16+32+q4=27   OR   p+q=60  (or equvalent)      (A1)(ft)  (C1)

\n


Note: Follow through from part (a).

\n


[1 mark]

\n
c.
\n
\n

5cm       (A1)(ft)  (C1)

\n


Note: Follow through from parts (b) and (c).

\n


[1 mark]

\n
d.i.
\n
\n

55cm       (A1)(ft)  (C1)

\n


Note: Follow through from parts (b) and (c).

\n


[1 mark]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "20N.1.SL.TZ0.T_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

A balloon in the shape of a sphere is filled with helium until the radius is 6 cm.

\n
\n

The volume of the balloon is increased by 40%.

\n
\n

Calculate the volume of the balloon.

\n
[2]
\n
a.
\n
\n

Calculate the radius of the balloon following this increase.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

Units are required in parts (a) and (b).

\n

\n\n4\n3\n\nπ\n×\n\n\n6\n3\n\n\n    (M1)

\n

 

\n

Note:     Award (M1) for correct substitution into volume of sphere formula.

\n

 

\n

\n=\n905\n\n c\n\n\n\n\nm\n\n3\n\n\n\n \n\n(\n288\nπ\n\n c\n\n\n\n\nm\n\n3\n\n\n,\n\n \n\n904.778\n\n\n c\n\n\n\n\nm\n\n3\n\n\n)\n    (A1)     (C2)

\n

 

\n

Note:     Answers derived from the use of approximations of \nπ\n (3.14; 22/7) are awarded (A0).

\n

 

\n

[2 marks]

\n
a.
\n
\n

Units are required in parts (a) and (b).

\n

\n\n\n140\n\n\n100\n\n\n×\n904.778\n\n=\n\n4\n3\n\nπ\n\n\nr\n3\n\n\n OR \n\n\n140\n\n\n100\n\n\n×\n288\nπ\n=\n\n4\n3\n\nπ\n\n\nr\n3\n\n\n OR \n1266.69\n\n=\n\n4\n3\n\nπ\n\n\nr\n3\n\n\n     (M1)(M1)

\n

 

\n

Note:     Award (M1) for multiplying their part (a) by 1.4 or equivalent, (M1) for equating to the volume of a sphere formula.

\n

 

\n

\n\n\nr\n3\n\n\n=\n\n\n3\n×\n1266.69\n\n\n\n4\nπ\n\n\n OR \nr\n=\n\n\n\n\n3\n×\n1266.69\n\n\n\n4\nπ\n\n\n\n3\n\n OR \nr\n=\n\n\n(\n1.4\n)\n×\n\n\n6\n3\n\n\n\n3\n\n OR \n\n\nr\n3\n\n\n=\n302.4\n     (M1)

\n

 

\n

Note:     Award (M1) for isolating \nr\n.

\n

 

\n

\n(\nr\n=\n)\n\n \n\n6.71\n\n cm \n\n(\n6.71213\n\n)\n     (A1)(ft)     (C4)

\n

 

\n

Note:     Follow through from part (a).

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.T_7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

Consider the function fx=-2x-1x+3, for x. The following diagram shows part of the graph of f.

\n

\n

 

\n
\n

For the graph of f

\n
\n

find the x-coordinates of the x-intercepts.

\n
[2]
\n
a.i.
\n
\n

find the coordinates of the vertex.

\n
[3]
\n
a.ii.
\n
\n

The function f can be written in the form fx=-2x-h2+k.

\n

Write down the value of h and the value of k.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

setting fx=0                (M1)

\n

x=1, x=-3 (accept 1,0,-3,0)                   A1

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

METHOD 1

\n

x=-1 A1

\n

substituting their x-coordinate into f                (M1)

\n

y=8                  A1

\n

-1,8

\n

 

\n

METHOD 2

\n

attempt to complete the square   (M1)

\n

-2x+12-4              (M1)

\n

x=-1, y=8                  A1A1

\n

 -1,8

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

h=-1                 A1

\n

k=8                 A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.1.SL.TZ0.1", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-6-quadratic-function" ] }, { "Question": "
\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n\n48\n\nx\n\n+\nk\n\n\nx\n2\n\n\n\n58\n, where x > 0 and k is a constant.

\n

The graph of the function passes through the point with coordinates (4 , 2).

\n
\n

P is the minimum point of the graph of f (x).

\n
\n

Sketch the graph of y = f (x) for 0 < x ≤ 6 and −30 ≤ y ≤ 60.
Clearly indicate the minimum point P and the x-intercepts on your graph.

\n
", "Markscheme": "
\n

(A1)(A1)(ft)(A1)(ft)(A1)(ft)

\n

Note: Award (A1) for correct window. Axes must be labelled.
(A1)(ft) for a smooth curve with correct shape and zeros in approximately correct positions relative to each other.
(A1)(ft) for point P indicated in approximately the correct position. Follow through from their x-coordinate in part (c). (A1)(ft) for two x-intercepts identified on the graph and curve reflecting asymptotic properties.

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.2.SL.TZ1.T_4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing" ] }, { "Question": "
\n

Consider the curve C defined by y2=sinxy , y0.

\n
\n

Show that dydx=ycosxy2y-xcosxy.

\n
[5]
\n
a.
\n
\n

Prove that, when dydx=0 , y=±1.

\n
[5]
\n
b.
\n
\n

Hence find the coordinates of all points on C, for 0<x<4π, where dydx=0.

\n
[5]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt at implicit differentiation       M1

\n

2ydydx=cosxyxdydx+y       A1M1A1

\n


Note: Award A1 for LHS, M1 for attempt at chain rule, A1 for RHS.

\n


2ydydx=xdydxcosxy+ycosxy

\n

2ydydx-xdydxcosxy=ycosxy

\n

dydx2y-xcosxy=ycosxy       M1

\n


Note: Award M1 for collecting derivatives and factorising.

\n


dydx=ycosxy2y-xcosxy       AG

\n


[5 marks]

\n
a.
\n
\n

setting dydx=0

\n

ycosxy=0       (M1)

\n

y0cosxy=0       A1

\n

sinxy=±1-cos2xy=±1-0=±1  OR  xy=2n+1π2n  OR  xy=π2, 3π2,       A1

\n


Note: If they offer values for xy, award A1 for at least two correct values in two different ‘quadrants’ and no incorrect values.

\n


y2=sinxy>0       R1

\n

y2=1       A1

\n

y=±1       AG

\n


[5 marks]

\n
b.
\n
\n

y=±11=sin±xsinx=±1  OR  y=±10=cos±xcosx=0       (M1)

\n

sinx=1π2,1,5π2,1       A1A1

\n

sinx=-13π2,-1,7π2,-1       A1A1

\n


Note:
Allow ‘coordinates’ expressed as x=π2, y=1 for example.
Note: Each of the A marks may be awarded independently and are not dependent on (M1) being awarded.

\n

Note: Mark only the candidate’s first two attempts for each case of sinx.

\n

[5 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "20N.1.AHL.TZ0.H_11", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Give your answers in this question correct to the nearest whole number.

\n

Imon invested 25000 Singapore dollars (SGD) in a fixed deposit account with a nominal annual interest rate of 3.6%, compounded monthly.

\n
\n

Calculate the value of Imon’s investment after 5 years.

\n
[3]
\n
a.
\n
\n

At the end of the 5 years, Imon withdrew x SGD from the fixed deposit account and reinvested this into a super-savings account with a nominal annual interest rate of 5.7%, compounded half-yearly.

\n

The value of the super-savings account increased to 20000 SGD after 18 months.

\n

Find the value of x.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure. It appeared in a paper that permitted the use of a calculator, and so might not be suitable for all forms of practice.

FV= 25000×1+3.6100×1212×5       (M1)(A1)

\n

Note: Award (M1) for substituted compound interest formula, (A1) for correct substitutions.

OR

N=5
I%=3.6
PV=25000
P/Y=1
C/Y=12       (A1)(M1)

Note: Award (A1) for C/Y=12 seen, (M1) for all other correct entries.

OR

N=60
I%=3.6
PV=25000
P/Y=12
C/Y=12       (A1)(M1)

Note: Award (A1) for C/Y=12 seen, (M1) for all other correct entries.

FV= 29922 SGD      (A1)   (C3)

Note: Do not award the final (A1) if answer is not given correct to the nearest integer.

[3 marks]

\n
a.
\n
\n

20000=PV×1+5.7100×22×1.5       (M1)(A1)

\n

Note: Award (M1) for substituted compound interest equated to 20000. Award (A1) for correct substitutions.

OR

N=1.5
I%=5.7
FV=±20000
P/Y=1
C/Y=2       (A1)(M1)

Note: Award (A1) for C/Y=2 seen, (M1) for all other correct entries.

OR

N=3
I%=5.7
FV=±20000
P/Y=2
C/Y=2       (A1)(M1)

Note: Award (A1) for C/Y=2 seen, (M1) for all other correct entries.

x= 18383 SGD      (A1)   (C3)

Note: Do not award the final (A1) if answer is not given correct to the nearest integer (unless already penalized in part(a)).

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.1.SL.TZ0.T_8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

Consider the curve y = 2x3 − 9x2 + 12x + 2, for −1 < x < 3

\n
\n

Sketch the curve for −1 < x < 3 and −2 < y < 12.

\n
[4]
\n
a.
\n
\n

A teacher asks her students to make some observations about the curve.

\n

Three students responded.
Nadia said “The x-intercept of the curve is between −1 and zero”.
Rick said “The curve is decreasing when x < 1 ”.
Paula said “The gradient of the curve is less than zero between x = 1 and x = 2 ”.

\n

State the name of the student who made an incorrect observation.

\n
[1]
\n
b.
\n
\n

Find dy dx .

\n
[3]
\n
d.
\n
\n

Show that the stationary points of the curve are at x = 1 and x = 2.

\n
[2]
\n
e.
\n
\n

Given that y = 2x3 − 9x2 + 12x + 2 = k has three solutions, find the possible values of k.

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

(A1)(A1)(A1)(A1)

\n

Note: Award (A1) for correct window (condone a window which is slightly off) and axes labels. An indication of window is necessary. −1 to 3 on the x-axis and −2 to 12 on the y-axis and a graph in that window.
(A1) for correct shape (curve having cubic shape and must be smooth).
(A1) for both stationary points in the 1st quadrant with approximate correct position,
(A1) for intercepts (negative x-intercept and positive y intercept) with approximate correct position.

\n

[4 marks]

\n
a.
\n
\n

Rick     (A1)

\n

Note: Award (A0) if extra names stated.

\n

[1 mark]

\n
b.
\n
\n

6x2 − 18x + 12     (A1)(A1)(A1)

\n

Note: Award (A1) for each correct term. Award at most (A1)(A1)(A0) if extra terms seen.

\n

[3 marks]

\n
d.
\n
\n

6x2 − 18x + 12 = 0     (M1)

\n

Note: Award (M1) for equating their derivative to 0. If the derivative is not explicitly equated to 0, but a subsequent solving of their correct equation is seen, award (M1).

\n

6( − 1)(x − 2) = 0  (or equivalent)      (M1)

\n

Note: Award (M1) for correct factorization. The final (M1) is awarded only if answers are clearly stated.

\n

Award (M0)(M0) for substitution of 1 and of 2 in their derivative.

\n

x = 1, x = 2 (AG)

\n

[2 marks]

\n
e.
\n
\n

6 < k < 7     (A1)(A1)(ft)(A1)

\n

Note: Award (A1) for an inequality with 6, award (A1)(ft) for an inequality with 7 from their part (c) provided it is greater than 6, (A1) for their correct strict inequalities. Accept ]6, 7[ or (6, 7).

\n

[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "18M.2.SL.TZ2.T_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-2-increasing-and-decreasing-functions" ] }, { "Question": "
\n

On a school excursion, 100 students visited an amusement park. The amusement park’s main attractions are rollercoasters (R), water slides (W), and virtual reality rides (V).

\n

The students were asked which main attractions they visited. The results are shown in the Venn diagram.

\n

\n

A total of 74 students visited the rollercoasters or the water slides.

\n
\n

Find the value of a.

\n
[2]
\n
a.i.
\n
\n

Find the value of b.

\n
[2]
\n
a.ii.
\n
\n

Find the number of students who visited at least two types of main attraction.

\n
[2]
\n
b.
\n
\n

Write down the value of n( RW) .

\n
[1]
\n
c.
\n
\n

Find the probability that a randomly selected student visited the rollercoasters.

\n
[2]
\n
d.i.
\n
\n

Find the probability that a randomly selected student visited the virtual reality rides.

\n
[1]
\n
d.ii.
\n
\n

Hence determine whether the events in parts (d)(i) and (d)(ii) are independent. Justify your reasoning. 

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

74-32+12+10+9+5  OR  74-68     (M1)

\n


Note: Award (M1) for setting up a correct expression.

\n


a=  6       (A1)(G2)

\n


[2 marks]

\n
a.i.
\n
\n

100-74+18     (M1)

\n

OR

\n

100-92     (M1)

\n

OR

\n

100-32+9+5+12+10+18+6     (M1)

\n


Note:
Award (M1) for setting up a correct expression. Follow through from part (a)(i) but only for a0.

\n


b=  8       (A1)(ft)(G2)

\n


Note:
Follow through from part(a)(i). The value of b must be greater or equal to zero for the (A1)(ft) to be awarded.

\n


[2 marks]

\n
a.ii.
\n
\n

9+5+12+10     (M1)

\n


Note:
Award (M1) for adding 9, 5, 12 and 10.

\n


36       (A1)(G2)

\n


[2 marks]

\n
b.
\n
\n

14     (A1)

\n

[1 mark]

\n
c.
\n
\n

58100  2950, 0.58, 58%     (A1)(A1)(G2)

\n


Note: Award (A1) for correct numerator. Award(A1) for the correct denominator. Award (A0) for 58 only.

\n


[2 marks]

\n
d.i.
\n
\n

45100  920, 0.45, 45%     (A1)(ft)

\n


Note: Follow through from their denominator from part (d)(i).

\n


[1 mark]

\n
d.ii.
\n
\n

they are not independent     (A1)(ft)

\n

58100×4510017100  OR  0.2610.17     (R1)

\n


Note: Comparison of numerical values must be seen for (R1) to be awarded.
Do not award (A1)(R0). Follow through from parts (d)(i) and (d)(ii).

\n


[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "20N.2.SL.TZ0.T_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Jashanti is saving money to buy a car. The price of the car, in US Dollars (USD), can be modelled by the equation

\n

\nP\n=\n8500\n\n \n\n\n(\n0.95\n\n)\nt\n\n\n.\n

\n

Jashanti’s savings, in USD, can be modelled by the equation

\n

\nS\n=\n400\nt\n+\n2000.\n

\n

In both equations \nt\n is the time in months since Jashanti started saving for the car.

\n
\n

Jashanti does not want to wait too long and wants to buy the car two months after she started saving. She decides to ask her parents for the extra money that she needs.

\n
\n

Write down the amount of money Jashanti saves per month.

\n
[1]
\n
a.
\n
\n

Use your graphic display calculator to find how long it will take for Jashanti to have saved enough money to buy the car.

\n
[2]
\n
b.
\n
\n

Calculate how much extra money Jashanti needs.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

400 (USD)     (A1)     (C1)

\n

[1 mark]

\n
a.
\n
\n

8500   ( 0.95 ) t = 400 × t + 2000     (M1)

\n

 

\n

Note:     Award (M1) for equating 8500 ( 0.95 ) t to 400 × t + 2000 or for comparing the difference between the two expressions to zero or for showing a sketch of both functions.

\n

 

\n

( t = )   8.64  (months)  ( 8.6414  (months) )     (A1)     (C2)

\n

 

\n

Note:     Accept 9 months.

\n

 

\n

[2 marks]

\n
b.
\n
\n

8500 ( 0.95 ) 2 ( 400 × 2 + 2000 )     (M1)(M1)

\n

 

\n

Note:     Award (M1) for correct substitution of t = 2 into equation for P , (M1) for finding the difference between a value/expression for P and a value/expression for S . The first (M1) is implied if 7671.25 seen.

\n

 

\n

4870 (USD) (4871.25)     (A1)     (C3)

\n

 

\n

Note:     Accept 4871.3.

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.T_14", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

Given that dydx=cosx-π4 and y=2 when x=3π4, find y in terms of x.

\n
", "Markscheme": "
\n

METHOD 1

\n

recognition that y=cosx-π4dx                 (M1)

\n

y=sinx-π4+c                 (A1)

\n

substitute both x and y values into their integrated expression including c                 (M1)

\n

2=sinπ2+c

\n

c=1

\n

y=sinx-π4+1                 A1

\n

 

\n

METHOD 2

\n

2ydy=3π4xcosx-π4dx                 (M1)(A1)

\n

y-2=sinx-π4-sinπ2                 A1

\n

y=sinx-π4+1                 A1

\n

 

\n

[4 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21N.1.SL.TZ0.2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

The function \nf\n is of the form \nf\n(\nx\n)\n=\na\nx\n+\nb\n+\n\nc\nx\n\n, where \na\n , \nb\n and \nc\n are positive integers.

\n

Part of the graph of \ny\n=\nf\n(\nx\n)\n is shown on the axes below. The graph of the function has its local maximum at \n(\n\n2\n,\n\n \n\n\n2\n)\n and its local minimum at \n(\n2\n,\n\n \n\n6\n)\n.

\n

\"M17/5/MATSD/SP1/ENG/TZ1/12\"

\n
\n

Draw the line y = 6 on the axes.

\n
[1]
\n
b.i.
\n
\n

Write down the number of solutions to f ( x ) = 6 .

\n
[1]
\n
b.ii.
\n
\n

Find the range of values of k for which f ( x ) = k has no solution.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

\"M17/5/MATSD/SP1/ENG/TZ1/21.b.i/M\"     (A1)     (C1)

\n

 

\n

Note:     The command term “Draw” states: “A ruler (straight edge) should be used for straight lines”; do not accept a freehand y = 6 line.

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

2     (A1)(ft)     (C1)

\n

 

\n

Note:     Follow through from part (b)(i).

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

2 < k < 6     (A1)(A1)     (C2)

\n

 

\n

Note:     Award (A1) for both end points correct and (A1) for correct strict inequalities.

\n

Award at most (A1)(A0) if the stated variable is different from k or y for example 2 < x < 6 is (A1)(A0).

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ1.T_12", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Consider the function defined by fx=kx-5x-k, where x\\k and k25

\n
\n

Consider the case where k=3.

\n
\n

State the equation of the vertical asymptote on the graph of y=f(x).

\n
[1]
\n
a.
\n
\n

State the equation of the horizontal asymptote on the graph of y=f(x).

\n
[1]
\n
b.
\n
\n

Use an algebraic method to determine whether f is a self-inverse function.

\n
[4]
\n
c.
\n
\n

Sketch the graph of y=f(x), stating clearly the equations of any asymptotes and the coordinates of any points of intersections with the coordinate axes.

\n
[3]
\n
d.
\n
\n

The region bounded by the x-axis, the curve y=f(x), and the lines x=5 and x=7 is rotated through 2π about the x-axis. Find the volume of the solid generated, giving your answer in the form π(a+b ln2) , where a, b.

\n
[6]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

x=k      A1

\n


[1 mark]

\n
a.
\n
\n

y=k      A1

\n


[1 mark]

\n
b.
\n
\n

METHOD 1

\n

ffx=kkx-5x-k-5kx-5x-k-k        M1

\n

=kkx-5-5x-kkx-5-kx-k        A1

\n

=k2x-5k-5x+5kkx-5-kx+k2

\n

=k2x-5xk2-5        A1

\n

=xk2-5k2-5

\n

=x

\n

ffx=x , (hence f is self-inverse)        R1

\n


Note:
The statement f(f(x))=x could be seen anywhere in the candidate’s working to award R1.

\n

 

\n

METHOD 2

\n

fx=kx-5x-k

\n

x=ky-5y-k        M1

\n


Note:
Interchanging x and y can be done at any stage.

\n


xy-k=ky-5        A1

\n

xy-xk=ky-5

\n

xy-ky=xk-5

\n

yx-k=kx-5        A1

\n

y=f-1x=kx-5x-k  (hence f is self-inverse)        R1

\n


[4 marks]

\n
c.
\n
\n

\n

attempt to draw both branches of a rectangular hyperbola        M1

\n

x=3 and y=3        A1

\n

0, 53 and 53, 0        A1

\n


[3 marks]

\n
d.
\n
\n

METHOD 1

\n

volume=π573x-5x-32dx       (M1)

\n

EITHER

\n

attempt to express 3x-5x-3 in the form p+qx-3       M1

\n

3x-5x-3=3+4x-3       A1

\n

OR

\n

attempt to expand 3x-5x-32 or 3x-52 and divide out       M1

\n

3x-5x-32=9+24x-56x-32       A1

\n

THEN

\n

3x-5x-32=9+24x-3+16x-32       A1

\n

volume=π579+24x-3+16x-32dx

\n

=π9x+24lnx-3-16x-357       A1

\n

=π63+24ln4-4-45+24ln2-8

\n

=π22+24ln2       A1

\n

 

\n

METHOD 2

\n

volume=π573x-5x-32dx       (M1)

\n

substituting u=x-3dudx=1       A1

\n

3x-5=3u+3-5=3u+4

\n

volume=π243u+4u2du       M1

\n

=π249+16u2+24udu       A1

\n

=π9u-16u+24lnu24       A1

\n


Note: Ignore absence of or incorrect limits seen up to this point.

\n


=π22+24ln2       A1

\n


[6 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "20N.1.AHL.TZ0.H_12", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Find the equation of the tangent to the curve y=e2x3x at the point where x=0.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

x=0y=1        (A1)

\n

appreciate the need to find dydx        (M1)

\n

dydx=2e2x-3        A1

\n

x=0dydx=-1        A1

\n

y-1x-0=-1   y=1-x        A1

\n


[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.1.AHL.TZ0.H_2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Consider the equation 2z3-z*=i, where z=x+iy and x, y.

\n

Find the value of x and the value of y.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

substituting z=x+iy and z*=x-iy        M1

\n

2x+iy3-x-iy=i

\n

2x+2iy=-y+i3-x      

\n

equate real and imaginary:        M1

\n

y=-2x  AND  2y=3-x       A1

\n


Note: If they multiply top and bottom by the conjugate, the equations 6x-2x2+2y2=0 and 6y-4xy=3-x2+y2 may be seen. Allow for A1.

\n


solving simultaneously:

\n

x=-1, y=2  z=-1+2i      A1A1

\n


[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.1.AHL.TZ0.H_4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

The first term in an arithmetic sequence is 4 and the fifth term is log2625.

\n

Find the common difference of the sequence, expressing your answer in the form log2p, where p.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

u5=4+4d=log2625      (A1)

\n

4d=log2625-4

\n

attempt to write an integer (eg 4 or 1) in terms of log2        M1

\n

4d=log2625-log216

\n

attempt to combine two logs into one        M1

\n

4d=log262516

\n

d=14log262516

\n

attempt to use power rule for logs        M1

\n

d=log26251614

\n

d=log252       A1

\n


[5 marks]

\n


Note: Award method marks in any order.

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.1.AHL.TZ0.H_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

The plane Π1 has equation 3xy+z=13 and the line L has vector equation

\n

r=12-2+λ-3-14 , λ.

\n
\n

The plane Π2 contains the point O and the line L.

\n
\n

Given that L meets Π1 at the point P, find the coordinates of P.

\n
[4]
\n
a.
\n
\n

Find the shortest distance from the point O(0, 0, 0) to Π1.

\n
[4]
\n
b.
\n
\n

Find the equation of Π2, giving your answer in the form r.n=d.

\n
[3]
\n
c.
\n
\n

Determine the acute angle between Π1 and Π2.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

31-3λ-2-λ+-2+4λ=-13        (M1)

\n

λ=3         (A1)

\n

r=12-2+3-3-14=8-110        (M1)

\n

so  P-8, -1, 10         A1

\n


Note:
Do not award the final A1 if a vector given instead of coordinates

\n


[4 marks]

\n
a.
\n
\n

METHOD 1

\n

r=μ3-11

\n

substituting into equation of the plane       M1

\n

9μ+μ+μ=-13

\n

μ=-1311 =-1.18       A1

\n

distance =1332+-12+1211        (M1)

\n

=1311=131111=3.92       A1

\n



METHOD 2

\n

choice of any point on the plane, eg -8, -1, 10 to use in distance formula        (M1)

\n

so distance =-8-110·-31-1-32+12+-12       A1A1

\n


Note: Award A1 for numerator, A1 for denominator.

\n


=24-1-1011

\n

=1311=131111=3.92       A1

\n


[4 marks]

\n
b.
\n
\n

EITHER

\n

identify two vectors        (A1)

\n

eg12-2 and -3-14

\n

n=12-2×-3-14=625        (M1)

\n


OR

\n


identify three points in the plane        (A1)

\n

eg  λ=0,1 gives 12-2 and -212

\n

solving system of equations        (M1)

\n


THEN

\n


Π2:r.625=0        A1

\n


Note: Accept 6x+2y+5z=0.

\n


[3 marks]

\n
c.
\n
\n

vector normal to Π1 is eg n1=3-11

\n

vector normal to Π2 is eg n2=625        (A1)

\n

required angle is θ, where cosθ3-11·6251165        M1A1

\n

cosθ=211165=0.785        (A1)

\n

θ=0.667526

\n

θ=0.668  =38.2°      A1

\n

Note: Award the penultimate (A1) but not the final A1 for the obtuse angle 2.47406 or 142°.

\n


[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "20N.2.AHL.TZ0.H_10", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-16-vector-product" ] }, { "Question": "
\n

Using geometry software, Pedro draws a quadrilateral ABCD. AB=8cm and CD=9cm. Angle BAD=51.5° and angle ADB=52.5°. This information is shown in the diagram.

\n

\n
\n

CE=7cm, where point E is the midpoint of BD.

\n
\n

Calculate the length of BD.

\n
[3]
\n
a.
\n
\n

Show that angle EDC=48.0°, correct to three significant figures.

\n
[4]
\n
b.
\n
\n

Calculate the area of triangle BDC.

\n
[3]
\n
c.
\n
\n

Pedro draws a circle, with centre at point E, passing through point C. Part of the circle is shown in the diagram.

\n

\n

Show that point A lies outside this circle. Justify your reasoning.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

BDsin51.5°=8sin52.5°      (M1)(A1)

\n


Note: Award (M1) for substituted sine rule, (A1) for correct substitution.

\n


BD=  7.89 cm  7.89164      (A1)(G2)

\n


Note: If radians are used the answer is 9.58723 award at most (M1)(A1)(A0).

\n


[3 marks]

\n
a.
\n
\n

cosEDC=92+3.945822-722×9×3.94582      (A1)(ft)(M1)(A1)(ft)

\n


Note: Award (A1) for 3.94582 or 7.891642 seen, (M1) for substituted cosine rule, (A1)(ft) for correct substitutions.

\n


EDC=  47.9515°      (A1)

\n

48.0° (3 sig figures)      (AG)

\n


Note: Both an unrounded answer that rounds to the given answer and the rounded value must be seen for the final (M1) to be awarded.
Award at most (A1)(ft)(M1)(A1)(ft)(A0) if the known angle 48.0° is used to validate the result. Follow through from their BD in part (a).

\n


[4 marks]

\n
b.
\n
\n

Units are required in this question.

\n


area= 12×7.89164×9×sin48.0° 
     (M1)(A1)(ft)

\n


Note: Award (M1) for substituted area formula. Award (A1) for correct substitution.

\n


area= 26.4cm2  26.3908      (A1)(ft)(G3)

\n


Note: Follow through from part (a).

\n


[3 marks]

\n
c.
\n
\n

AE2=82+3.945822-2×8×3.94582cos76°        (A1)(M1)(A1)(ft)

\n


Note: Award (A1) for 76° seen. Award (M1) for substituted cosine rule to find AE, (A1)(ft) for correct substitutions.

\n


AE=  8.02cm  8.01849      (A1)(ft)(G3)

\n


Note: Follow through from part (a).

\n


OR

\n


AE2=9.784242+3.945822-2×9.78424×3.94582cos52.5°        (A1)(M1)(A1)(ft)

\n


Note: Award (A1) for AD (9.78424) or 76° seen. Award (M1) for substituted cosine rule to find AE (do not award (M1) for cosine or sine rule to find AD), (A1)(ft) for correct substitutions.

\n

 

\n

AE=  8.02cm  8.01849      (A1)(ft)(G3)

\n


Note: Follow through from part (a).

\n


8.02>7.      (A1)(ft)

\n

point A is outside the circle.      (AG)

\n


Note: Award (A1) for a numerical comparison of AE and CE. Follow through for the final (A1)(ft) within the part for their 8.02. The final (A1)(ft) is contingent on a valid method to find the value of AE.
Do not award the final (A1)(ft) if the (AG) line is not stated.
Do not award the final (A1)(ft) if their point A is inside the circle.

\n


[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "20N.2.SL.TZ0.T_3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A particle P moves in a straight line such that after time t seconds, its velocity, v in m s-1, is given by v=e3tsin6t, where 0<t<π2.

\n
\n

At time t, P has displacement s(t); at time t=0, s(0)=0.

\n
\n

At successive times when the acceleration of P is 0m s2 , the velocities of P form a geometric sequence. The acceleration of P is zero at times t1, t2, t3 where t1<t2<t3 and the respective velocities are v1, v2, v3.

\n
\n

Find the times when P comes to instantaneous rest.

\n
[2]
\n
a.
\n
\n

Find an expression for s in terms of t.

\n
[7]
\n
b.
\n
\n

Find the maximum displacement of P, in metres, from its initial position.

\n
[2]
\n
c.
\n
\n

Find the total distance travelled by P in the first 1.5 seconds of its motion.

\n
[2]
\n
d.
\n
\n

Show that, at these times, tan6t=2.

\n
[2]
\n
e.i.
\n
\n

Hence show that v2v1=v3v2=-e-π2.

\n
[5]
\n
e.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

π6=0.524      A1

\n

π3=1.05      A1

\n


[2 marks]

\n
a.
\n
\n

attempt to use integration by parts        M1

\n

s=e-3tsin6t dt

\n


EITHER

\n


=-e-3tsin6t3--2e-3t cos6t dt      A1

\n

=-e-3tsin6t3-2e-3t cos6t3--4e-3t sin6t dt      A1

\n

=-e-3tsin6t3-2e-3t cos6t3+4s

\n

5s=-3e-3tsin6t-6e-3t cos6t9        M1

\n


OR

\n


=-e-3t cos6t6-12e-3t cos6t dt      A1

\n

=-e-3t cos6t6-e-3t sin6t12+14e-3t sin6t dt      A1

\n

=-e-3t cos6t6-e-3t sin6t12+14s

\n

54s=-2e-3t cos6t-e-3t sin6t12        M1

\n


THEN

\n


s=-e-3t sin6t+2cos6t15+c      A1

\n

at t=0, s=00=-215+c        M1

\n

c=215      A1

\n

s=215-e-3t sin6t+2cos6t15

\n


[7 marks]

\n
b.
\n
\n

EITHER

\n

substituting t=π6 into their equation for s         (M1)

\n

s=215-e-π2 sinπ+2cosπ15

\n


OR

\n

using GDC to find maximum value         (M1)

\n

OR

\n

evaluating 0π6vdt         (M1)

\n


THEN

\n


=0.161=2151+e-π2       A1 

\n


[2 marks]

\n
c.
\n
\n

METHOD 1 

\n


EITHER

\n

distance required =01.5e-3tsin6tdt       (M1)

\n


OR

\n

distance required =0π6e-3tsin6tdt+π6π3e-3tsin6tdt+π31.5e-3tsin6tdt       (M1)

\n

=0.16105+0.033479+0.006806

\n


THEN

\n


=0.201 m       A1

\n

 

\n

METHOD 2

\n


using successive minimum and maximum values on the displacement graph       (M1)

\n

0.16105+0.16105-0.12757+0.13453-0.12757

\n

=0.201 m       A1

\n


[2 marks]

\n
d.
\n
\n

valid attempt to find dvdt using product rule and set dvdt=0       M1

\n

dvdt=e-3t6cos6t-3e-3tsin6t        A1

\n

dvdt=0tan6t=2        AG

\n


[2 marks]

\n
e.i.
\n
\n

attempt to evaluate t1, t2, t3 in exact form         M1

\n

6t1=arctan2t1=16arctan2

\n

6t2=π+arctan2t2=π6+16arctan2

\n

6t3=2π+arctan2t3=π3+16arctan2       A1

\n


Note: The A1 is for any two consecutive correct, or showing that 6t2=π+6t1 or 6t3=π+6t2.

\n


showing that sin6tn+1=-sin6tn

\n

eg  tan6t=2sin6t=±25         M1A1

\n

showing that e-3tn+1e-3tn=e-π2         M1

\n

eg   e-3π6+k÷e-3k=e-π2

\n


Note: Award the A1 for any two consecutive terms.

\n


v3v2=v2v1=-e-π2        AG

\n


[5 marks]

\n
e.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
", "question_id": "20N.2.AHL.TZ0.H_11", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

Hyungmin designs a concrete bird bath. The bird bath is supported by a pedestal. This is shown in the diagram.

\n

\n

The interior of the bird bath is in the shape of a cone with radius r, height h and a constant slant height of 50cm.

\n
\n

Let V be the volume of the bird bath.

\n
\n

Hyungmin wants the bird bath to have maximum volume.

\n
\n

Write down an equation in r and h that shows this information.

\n
[1]
\n
a.
\n
\n

Show that V=2500πh3-πh33.

\n
[1]
\n
b.
\n
\n

Find dVdh.

\n
[2]
\n
c.
\n
\n

Using your answer to part (c), find the value of h for which V is a maximum.

\n
[2]
\n
d.
\n
\n

Find the maximum volume of the bird bath.

\n
[2]
\n
e.
\n
\n

To prevent leaks, a sealant is applied to the interior surface of the bird bath.

\n

Find the surface area to be covered by the sealant, given that the bird bath has maximum volume.

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

h2+r2=502  (or equivalent)        (A1)

\n


Note: Accept equivalent expressions such as r=2500-h2 or h=2500-r2. Award (A0) for a final answer of ±2500-h2 or ±2500-r2, or any further incorrect working.

\n


[1 mark]

\n
a.
\n
\n

13×π×2500-h2×h  OR  13×π×2500-h22×h        (M1)

\n


Note: Award (M1) for correct substitution in the volume of cone formula.

\n


V=2500πh3-πh33        (AG)

\n


Note: The final line must be seen, with no incorrect working, for the (M1) to be awarded.

\n


[1 mark]

\n
b.
\n
\n

dVdh= 2500π3-πh2        (A1)(A1)

\n


Note: Award (A1) for 2500π3, (A1) for -πh2. Award at most (A1)(A0) if extra terms are seen. Award (A0) for the term -3πh23.

\n


[2 marks]

\n
c.
\n
\n

0=2500π3-πh2        (M1)

\n


Note:
Award (M1) for equating their derivative to zero. Follow through from part (c).

\n


OR

\n

sketch of dVdh        (M1)

\n


Note:
 Award (M1) for a labelled sketch of dVdh with the curve/axes correctly labelled or the x-intercept explicitly indicated.

\n


h=  28.9 cm  25003, 503, 5033, 28.8675       (A1)(ft)

\n


Note: An unsupported 28.9 cm is awarded no marks. Graphing the function Vh is not an acceptable method and (M0)(A0) should be awarded. Follow through from part (c). Given the restraints of the question, h50 is not possible.

\n


[2 marks]

\n
d.
\n
\n

V= 2500×π×28.86753-π28.867533        (M1)

\n

OR

\n

13π40.8282×28.8675        (M1)

\n


Note:
 Award (M1) for substituting their 28.8675 in the volume formula.

\n


V=  50400 cm3  50383.3       (A1)(ft)(G2)

\n


Note: Follow through from part (d).

\n


[2 marks]

\n
e.
\n
\n

S= π×2500-28.86752×50         (A1)(ft)(M1)

\n


Note:
 Award (A1) for their correct radius seen 40.8248, 2500-28.86752.
Award (M1) for correctly substituted curved surface area formula for a cone.

\n


S= 6410 cm2  6412.74       (A1)(ft)(G2)

\n


Note: Follow through from parts (a) and (d).

\n


[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "20N.2.SL.TZ0.T_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

A large underground tank is constructed at Mills Airport to store fuel. The tank is in the shape of an isosceles trapezoidal prism, ABCDEFGH.

\n

AB=70m , AF=200m, AD=40m, BC=40m and CD=110m. Angle ADC=60° and angle BCD=60°. The tank is illustrated below.

\n

\n
\n

Once construction was complete, a fuel pump was used to pump fuel into the empty tank. The amount of fuel pumped into the tank by this pump each hour decreases as an arithmetic sequence with terms u1, u2, u3, , un.

\n

Part of this sequence is shown in the table.

\n

\n
\n

At the end of the 2nd hour, the total volume of fuel in the tank was 88200m3.

\n
\n

Find h, the height of the tank.

\n
[2]
\n
a.
\n
\n

Show that the volume of the tank is 624000m3, correct to three significant figures.

\n
[3]
\n
b.
\n
\n

Write down the common difference, d.

\n
[1]
\n
c.
\n
\n

Find the amount of fuel pumped into the tank in the 13th hour.

\n
[2]
\n
d.
\n
\n

Find the value of n such that un=0.

\n
[2]
\n
e.i.
\n
\n

Write down the number of hours that the pump was pumping fuel into the tank.

\n
[1]
\n
e.ii.
\n
\n

Find the total amount of fuel pumped into the tank in the first 8 hours.

\n
[2]
\n
f.
\n
\n

Show that the tank will never be completely filled using this pump.

\n
[3]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

sin60°=h40  OR  tan60°=h20           (M1)

\n


Note:
 Award (M1) for correct substitutions in trig ratio.

\n


OR

\n

202+h2=402     402-202           (M1)

\n


Note: Award (M1) for correct substitutions in Pythagoras’ theorem.

\n


h= 34.6 m  1200, 203, 34.6410       (A1)(G2)

\n


[2 marks]

\n
a.
\n
\n

1270+11034.6410×200           (M1)(M1)

\n


Note:
Award (M1) for their correctly substituted area of trapezium formula, provided all substitutions are positive. Award (M1) for multiplying by 200. Follow through from part (a).

\n


OR

\n


2×12×20×34.6410+70×34.6410×200           (M1)(M1)

\n


Note: Award (M1) for the addition of correct areas for two triangles and one rectangle. Award (M1) for multiplying by 200. Follow through from part (a).

\n


OR

\n


70×34.6410×200+2×12×34.6410×20×200           (M1)(M1)

\n


Note:
 Award (M1) for their correct substitution in volume of cuboid formula. Award (M1) for correctly substituted volume of triangular prism(s). Follow through from part (a).

\n


623538         (A1)

\n

624000m3            (AG)

\n


Note:
Both an unrounded answer that rounds to the given answer and the rounded value must be seen for the (A1) to be awarded.

\n


[3 marks]

\n
b.
\n
\n

d=  -1800           (A1)

\n


[1 mark]

\n
c.
\n
\n

u13=   45000+13-1-1800           (M1)

\n


Note:
Award (M1) for correct substitutions in arithmetic sequence formula.
OR
Award (M1) for a correct 4th term seen as part of list.

\n


23400  m3        (A1)(ft)(G2)

\n


Note:
Follow through from part (c) for their value of d.

\n


[2 marks]

\n
d.
\n
\n

0=45000+n-1-1800           (M1)

\n


Note:
Award (M1) for their correct substitution into arithmetic sequence formula, equated to zero.

\n


n=   26        (A1)(ft)(G2)

\n


Note:
Follow through from part (c). Award at most (M1)(A0) if their n is not a positive integer.

\n


[2 marks]

\n
e.i.
\n
\n

25           (A1)(ft)

\n


Note:
Follow through from part (e)(i), but only if their final answer in (e)(i) is positive. If their n in part (e)(i) is not an integer, award  (A1)(ft) for the nearest lower integer.

\n


[1 mark]

\n
e.ii.
\n
\n

S8= 822×45000+8-1×-1800           (M1)

\n


Note:
Award (M1) for their correct substitutions in arithmetic series formula. If a list method is used, award (M1) for the addition of their 8 correct terms.

\n


310000 m3 309600       (A1)(ft)(G2)

\n


Note: Follow through from part (c). Award at most (M1)(A0) if their final answer is greater than 624000.

\n


[2 marks]

\n
f.
\n
\n

S25= 2522×45000+25-1×-1800  ,  S25= 25245000+1800           (M1)

\n


Note:
Award (M1) for their correct substitutions into arithmetic series formula.

\n


S25=585000 m3       (A1)(ft)(G1)

\n


Note: Award (M1)(A1) for correctly finding S26=585000 m3, provided working is shown e.g. S26= 2622×45000+26-1×-1800 , S26= 26245000+0. Follow through from part (c) and either their (e)(i) or (e)(ii). If d<0 and their final answer is greater than 624000, award at most (M1)(A1)(ft)(R0). If d>0, there is no maximum, award at most (M1)(A0)(R0). Award no marks if their number of terms is not a positive integer.

\n


585000 m3<624000 m3        (R1)

\n

Hence it will never be filled        (AG)

\n


Note: The (AG) line must be seen. If it is omitted do not award the final (R1). Do not follow through within the part.
For unsupported S25=585000 seen, award at most (G1)(R1)(AG). Working must be seen to follow through from parts (c) and (e)(i) or (e)(ii).

\n


OR

\n


Sn= n22×45000+n-1×-1800           (M1)

\n


Note: Award (M1) for their correct substitution into arithmetic series formula, with n.

\n


Maximum of this function 585225 m3       (A1)

\n


Note: Follow through from part (c). Award at most (M1)(A1)(ft)(R0) if their final answer is greater than 624000. Award at most (M1)(A0)(R0) if their common difference is not 1800. Award at most (M1)(A0)(R0) if 585225 is not explicitly identified as the maximum of the function.

\n


585225 m3<624000 m3        (R1)

Hence it will never be filled        (AG)

\n


Note: The (AG) line must be seen. If it is omitted do not award the final (R1). Do not follow through within the part.

\n


OR

\n


sketch with concave down curve and labelled 624000 horizontal line           (M1)

\n


Note: Accept a label of “tank volume” instead of a numerical value. Award (M0) if the line and the curve intersect.

\n


curve explicitly labelled as Sn= n22×45000+n-1×-1800 or equivalent       (A1)

Note:
Award (A1) for a written explanation interpreting the sketch. Accept a comparison of values, e.g 585225 m3<624000 m3, where 585225 is the graphical maximum. Award at most (M1)(A0)(R0) if their common difference is not 1800.

\n


the line and the curve do not intersect        (R1)

\n

hence it will never be filled        (AG)

\n


Note: The (AG) line must be seen. If it is omitted do not award the final (R1). Do not follow through within the part.

\n


OR

\n


624000=n22×45000+n-1×-1800           (M1)

\n


Note: Award (M1) for their correctly substituted arithmetic series formula equated to 624000 (623538).

\n


Demonstrates there is no solution       (A1)

\n


Note: Award (A1) for a correct working that the discriminant is less than zero OR correct working indicating there is no real solution in the quadratic formula.

\n


There is no (real) solution (to this equation)       (R1)

\n

hence it will never be filled        (AG)

\n


Note: At most (M1)(A0)(R0) for their correctly substituted arithmetic series formula =624000, 623538 or 622800 with a statement \"no solution\". Follow through from their part (b).

\n


[3 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "20N.2.SL.TZ0.T_5", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

There are three fair six-sided dice. Each die has two green faces, two yellow faces and two red faces.

\n

All three dice are rolled.

\n
\n

Ted plays a game using these dice. The rules are:

\n\n
\n

The random variable \nD\n ($) represents how much is added to his winnings after a turn.

\n

The following table shows the distribution for \nD\n, where $\nw\n represents his winnings in the game so far.

\n

\n
\n

Find the probability of rolling exactly one red face.

\n
[2]
\n
a.i.
\n
\n

Find the probability of rolling two or more red faces.

\n
[3]
\n
a.ii.
\n
\n

Show that, after a turn, the probability that Ted adds exactly $10 to his winnings is \n\n\n1\n3\n\n\n.

\n
[5]
\n
b.
\n
\n

Write down the value of \nx\n.

\n
[1]
\n
c.i.
\n
\n

Hence, find the value of \ny\n.

\n
[2]
\n
c.ii.
\n
\n

Ted will always have another turn if he expects an increase to his winnings.

\n

Find the least value of \nw\n for which Ted should end the game instead of having another turn.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

valid approach to find P(one red)     (M1)

\n

eg  \n\n\n\nn\n\n\n\nC\na\n\n\n×\n\n\np\na\n\n\n×\n\n\nq\n\nn\n\na\n\n\n\n,  \n\nB\n\n\n(\n\nn\n\n\n\np\n\n)\n\n,  \n3\n\n(\n\n\n1\n3\n\n\n)\n\n\n\n\n(\n\n\n2\n3\n\n\n)\n\n2\n\n\n,  \n\n(\n\n\n\n\n3\n\n\n\n\n1\n\n\n\n\n)\n\n

\n

listing all possible cases for exactly one red (may be indicated on tree diagram)

\n

P(1 red) = 0.444 \n\n(\n\n=\n\n4\n9\n\n\n)\n\n   [0.444, 0.445]           A1  N2

\n

 [3 marks] [5 maximum for parts (a.i) and (a.ii)]

\n
a.i.
\n
\n

valid approach     (M1)

\n

eg  P(\nX\n=\n2\n) + P(\nX\n=\n3\n), 1 − P(\nX\n ≤ 1),  binomcdf\n\n(\n\n3\n\n,\n\n\n\n\n1\n3\n\n\n,\n\n\n\n2\n\n,\n\n\n\n3\n\n)\n\n

\n

correct working       (A1)

\n

eg   \n\n2\n9\n\n+\n\n1\n\n27\n\n\n,   0.222 + 0.037 ,  \n1\n\n\n\n\n(\n\n\n2\n3\n\n\n)\n\n3\n\n\n\n\n4\n9\n\n

\n

0.259259

\n

P(at least two red) = 0.259 \n\n(\n\n=\n\n7\n27\n\n\n)\n\n          A1  N3

\n

[3 marks]  [5 maximum for parts (a.i) and (a.ii)]

\n
a.ii.
\n
\n

recognition that winning $10 means rolling exactly one green        (M1)

\n

recognition that winning $10 also means rolling at most 1 red        (M1)

\n

eg “cannot have 2 or more reds”

\n

correct approach        A1

\n

eg  P(1G ∩ 0R) + P(1G ∩ 1R),  P(1G) − P(1G ∩ 2R),

\n

      “one green and two yellows or one of each colour”

\n

Note: Because this is a “show that” question, do not award this A1 for purely numerical expressions.

\n

one correct probability for their approach        (A1)

\n

eg   \n3\n\n(\n\n\n1\n3\n\n\n)\n\n\n\n\n(\n\n\n1\n3\n\n\n)\n\n2\n\n\n,  \n\n\n6\n27\n\n\n\n3\n\n(\n\n\n1\n3\n\n\n)\n\n\n\n\n(\n\n\n2\n3\n\n\n)\n\n2\n\n\n\n\n\n1\n9\n\n\n,  \n\n\n2\n9\n\n\n

\n

correct working leading to \n\n\n1\n3\n\n\n      A1

\n

eg   \n\n3\n\n27\n\n\n+\n\n6\n\n27\n\n\n\n\n12\n\n27\n\n\n\n\n3\n\n27\n\n\n,  \n\n1\n\n9\n\n\n+\n\n2\n\n9\n\n\n

\n

probability = \n\n\n1\n3\n\n\n      AG N0

\n

[5 marks]

\n
b.
\n
\n

\nx\n=\n\n7\n\n27\n\n\n,  0.259 (check FT from (a)(ii))      A1 N1

\n

[1 mark]

\n
c.i.
\n
\n

evidence of summing probabilities to 1       (M1)

\n

eg   \n\n\n=\n1\n\n,  \nx\n+\ny\n+\n\n1\n3\n\n+\n\n2\n9\n\n+\n\n1\n\n27\n\n\n=\n1\n,  \n1\n\n\n7\n\n27\n\n\n\n\n9\n\n27\n\n\n\n\n6\n\n27\n\n\n\n\n1\n\n27\n\n\n

\n

0.148147  (0.148407 if working with their \nx\n value to 3 sf)

\n

\ny\n=\n\n4\n\n27\n\n\n  (exact), 0.148     A1 N2

\n

[2 marks]

\n
c.ii.
\n
\n

correct substitution into the formula for expected value      (A1)

\n

eg   \n\nw\n\n\n7\n\n27\n\n\n+\n10\n\n\n9\n\n27\n\n\n+\n20\n\n\n6\n\n27\n\n\n+\n30\n\n\n1\n\n27\n\n\n

\n

correct critical value (accept inequality)       A1

\n

eg   \nw\n = 34.2857  \n\n(\n\n=\n\n\n240\n\n7\n\n\n)\n\n\nw\n > 34.2857

\n

$40      A1 N2

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.2.SL.TZ1.S_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-5-probability-concepts-expected-numbers" ] }, { "Question": "
\n

In a group of 20 girls, 13 take history and 8 take economics. Three girls take both history and economics, as shown in the following Venn diagram. The values \np\n and \nq\n represent numbers of girls.

\n

\"M17/5/MATME/SP1/ENG/TZ1/01\"

\n
\n

Find the value of \np\n;

\n
[2]
\n
a.i.
\n
\n

Find the value of \nq\n.

\n
[2]
\n
a.ii.
\n
\n

A girl is selected at random. Find the probability that she takes economics but not history.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\np\n+\n3\n=\n13\n,\n\n \n\n13\n\n3\n

\n

\np\n=\n10\n     A1     N2

\n

[2 marks]

\n
a.i.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\np\n+\n3\n+\n5\n+\nq\n=\n20\n,\n\n \n\n10\n\n10\n\n8\n

\n

\nq\n=\n2\n     A1     N2

\n

[2 marks]

\n
a.ii.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n20\n\np\n\nq\n\n3\n,\n\n \n\n1\n\n\n\n15\n\n\n20\n\n\n,\n\n \n\nn\n(\nE\n\n\nH\n\n\n)\n=\n5\n

\n

\n\n5\n\n20\n\n\n\n\n\n\n(\n\n\n1\n4\n\n\n)\n\n     A1     N2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ1.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-5-probability-concepts-expected-numbers" ] }, { "Question": "
\n

A bag contains \nn\n marbles, two of which are blue. Hayley plays a game in which she randomly draws marbles out of the bag, one after another, without replacement. The game ends when Hayley draws a blue marble.

\n
\n

 Let \nn\n = 5. Find the probability that the game will end on her

\n
\n

Find the probability, in terms of \nn\n, that the game will end on her first draw.

\n
[1]
\n
a.i.
\n
\n

Find the probability, in terms of \nn\n, that the game will end on her second draw.

\n
[3]
\n
a.ii.
\n
\n

third draw.

\n
[2]
\n
b.i.
\n
\n

fourth draw.

\n
[2]
\n
b.ii.
\n
\n

Hayley plays the game when \nn\n = 5. She pays $20 to play and can earn money back depending on the number of draws it takes to obtain a blue marble. She earns no money back if she obtains a blue marble on her first draw. Let M be the amount of money that she earns back playing the game. This information is shown in the following table.

\n

\n

Find the value of \nk\n so that this is a fair game.

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

\n\n2\nn\n\n     A1 N1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

correct probability for one of the draws      A1

\n

eg   P(not blue first) = \n\n\nn\n\n2\n\nn\n\n,   blue second = \n\n2\n\nn\n\n1\n\n\n

\n

valid approach      (M1)

\n

eg   recognizing loss on first in order to win on second, P(B' then B),  P(B') × P(B | B'),  tree diagram

\n

correct expression in terms of \nn\n       A1 N3

\n

eg   \n\n\nn\n\n2\n\nn\n\n×\n\n2\n\nn\n\n1\n\n\n\n\n\n2\nn\n\n4\n\n\n\n\nn\n2\n\n\n\nn\n\n\n,  \n\n\n2\n\n(\n\nn\n\n2\n\n)\n\n\n\nn\n\n(\n\nn\n\n1\n\n)\n\n\n\n

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

correct working      (A1)

\n

eg   \n\n3\n5\n\n×\n\n2\n4\n\n×\n\n2\n3\n\n

\n

\n\n\n12\n\n\n60\n\n\n\n\n\n\n(\n\n=\n\n1\n5\n\n\n)\n\n     A1  N2

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

correct working      (A1)

\n

eg  \n\n3\n5\n\n×\n\n2\n4\n\n×\n\n1\n3\n\n×\n\n2\n2\n\n

\n

\n\n6\n\n60\n\n\n\n\n\n\n(\n\n=\n\n1\n\n10\n\n\n\n)\n\n    A1  N2

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

correct probabilities (seen anywhere)      (A1)(A1)

\n

eg   \n\nP\n\n\n(\n\n1\n\n)\n\n=\n\n2\n5\n\n,  \n\nP\n\n\n(\n\n2\n\n)\n\n=\n\n6\n\n20\n\n\n  (may be seen on tree diagram)

\n

valid approach to find E (M) or expected winnings using their probabilities      (M1)

\n

eg   \n\nP\n\n\n(\n\n1\n\n)\n\n×\n\n(\n0\n)\n\n+\n\nP\n\n\n(\n\n2\n\n)\n\n×\n\n(\n\n20\n\n)\n\n+\n\nP\n\n\n(\n\n3\n\n)\n\n×\n\n(\n\n8\nk\n\n)\n\n+\n\nP\n\n\n(\n\n4\n\n)\n\n×\n\n(\n\n12\nk\n\n)\n\n,

\n

\n\nP\n\n\n(\n\n1\n\n)\n\n×\n\n(\n\n\n20\n\n)\n\n+\n\nP\n\n\n(\n\n2\n\n)\n\n×\n\n(\n0\n)\n\n+\n\nP\n\n\n(\n\n3\n\n)\n\n×\n\n(\n\n8\nk\n\n20\n\n)\n\n+\n\nP\n\n\n(\n\n4\n\n)\n\n×\n\n(\n\n12\nk\n\n20\n\n)\n\n

\n

correct working to find E (M) or expected winnings      (A1)

\n

eg   \n\n2\n5\n\n\n(\n0\n)\n\n+\n\n3\n\n10\n\n\n\n(\n\n20\n\n)\n\n+\n\n1\n5\n\n\n(\n\n8\nk\n\n)\n\n+\n\n1\n\n10\n\n\n\n(\n\n12\nk\n\n)\n\n,

\n

\n\n2\n5\n\n\n(\n\n\n20\n\n)\n\n+\n\n3\n\n10\n\n\n\n(\n0\n)\n\n+\n\n1\n5\n\n\n(\n\n8\nk\n\n20\n\n)\n\n+\n\n1\n\n10\n\n\n\n(\n\n12\nk\n\n20\n\n)\n\n

\n

correct equation for fair game      A1

\n

eg   \n\n3\n\n10\n\n\n\n(\n\n20\n\n)\n\n+\n\n1\n5\n\n\n(\n\n8\nk\n\n)\n\n+\n\n1\n\n10\n\n\n\n(\n\n12\nk\n\n)\n\n=\n20\n\n\n2\n5\n\n\n(\n\n\n20\n\n)\n\n+\n\n1\n5\n\n\n(\n\n8\nk\n\n20\n\n)\n\n+\n\n1\n\n10\n\n\n\n(\n\n12\nk\n\n20\n\n)\n\n=\n0\n

\n

correct working to combine terms in \nk\n       (A1)

\n

eg   \n\n8\n+\n\n\n14\n\n5\n\nk\n\n4\n\n2\n=\n0\n,  \n6\n+\n\n\n14\n\n5\n\nk\n=\n20\n,  \n\n\n14\n\n5\n\nk\n=\n14\n

\n

\nk\n = 5    A1 N0

\n

Note: Do not award the final A1 if the candidate’s FT probabilities do not sum to 1.

\n

 

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.1.SL.TZ0.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-5-probability-concepts-expected-numbers" ] }, { "Question": "
\n

The following diagram shows part of the graph of y=p+qsin(rx) . The graph has a local maximum point at -9π4, 5 and a local minimum point at -3π4, -1.

\n

\n
\n

Determine the values of p, q and r.

\n
[4]
\n
a.
\n
\n

Hence find the area of the shaded region.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

the principal axis is 5+-12=2

\n

so p=2       A1

\n

the amplitude is 5--12=3

\n

so q=3       A1

\n


EITHER

\n

one period is 2-3π4--9π4       (M1)

\n

=3π

\n

2πr=3π

\n


OR

\n

Substituting a point eg -1=2+sin-3π4r

\n

sin-3π4r=-1-3π4r=-5π2, -π2, 3π2,

\n

Choice of correct solution -3π4r=-π2       (M1)

\n


THEN

\n

r=23       A1

\n

y=2+3sin2x3

\n


Note:
q and r can be both given as negatives for full marks

\n


[4 marks]

\n
a.
\n
\n

roots are x=-1.09459, x=-3.617797       (A1)

\n

-3.617797-1.094592+3sin2x3dx       (M1)

\n

=-1.66=-1.66179       (A1)

\n

so area =1.66  units2       A1

\n


[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.2.AHL.TZ0.H_3", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

At Penna Airport the probability, P(A), that all passengers arrive on time for a flight is 0.70. The probability, P(D), that a flight departs on time is 0.85. The probability that all passengers arrive on time for a flight and it departs on time is 0.65.

\n
\n

The number of hours that pilots fly per week is normally distributed with a mean of 25 hours and a standard deviation \nσ\n. 90 % of pilots fly less than 28 hours in a week.

\n
\n

Show that event A and event D are not independent.

\n
[2]
\n
a.
\n
\n

Find \n\nP\n\n\n(\n\nA\n\n\nD\n\n\n\n)\n\n.

\n
[2]
\n
b.i.
\n
\n

 Given that all passengers for a flight arrive on time, find the probability that the flight does not depart on time.

\n
[3]
\n
b.ii.
\n
\n

Find the value of \nσ\n.

\n
[3]
\n
c.
\n
\n

All flights have two pilots. Find the percentage of flights where both pilots flew more than 30 hours last week.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1

\n

multiplication of P(A) and P(D)     (A1)

\n

eg   0.70 × 0.85,  0.595

\n

correct reasoning for their probabilities       R1

\n

eg   \n0.595\n\n0.65\n,   \n0.70\n×\n0.85\n\n\nP\n\n\n(\n\nA\n\nD\n\n)\n\n

\n

A and D are not independent      AG N0

\n

 

\n

METHOD 2

\n

calculation of \n\nP\n\n\n(\n\nD\n\n|\nA\n\n\n\n)\n\n       (A1)

\n

eg   \n\n\n13\n\n\n14\n\n\n,  0.928

\n

correct reasoning for their probabilities       R1

\n

eg   \n0.928\n\n0.85\n,   \n\n\n0.65\n\n\n0.7\n\n\n\nP\n\n\n(\nD\n)\n\n

\n

A and D are not independent      AG N0

\n

[2 marks]

\n
a.
\n
\n

correct working       (A1)

\n

eg   \n\nP\n\n\n(\nA\n)\n\n\n\nP\n\n\n(\n\nA\n\nD\n\n)\n\n ,  0.7 − 0.65 , correct shading and/or value on Venn diagram

\n

\n\nP\n\n\n(\n\nA\n\n\nD\n\n\n\n)\n\n=\n0.05\n       A1  N2

\n

[2 marks]

\n

 

\n
b.i.
\n
\n

recognizing conditional probability (seen anywhere)       (M1)

\n

eg   \n\n\n\nP\n\n\n(\n\n\nD\n\n\n\nA\n\n)\n\n\n\n\nP\n\n\n(\nA\n)\n\n\n\n,  \n\nP\n\n\n(\n\nA\n\n|\nB\n\n\n\n)\n\n

\n

correct working       (A1)

\n

eg    \n\n\n0.05\n\n\n0.7\n\n\n

\n

0.071428

\n

\n\nP\n\n\n(\n\n\nD\n\n\n\n|\nA\n\n\n\n)\n\n=\n\n1\n\n14\n\n\n , 0.0714     A1  N2

\n

[3 marks]

\n
b.ii.
\n
\n

finding standardized value for 28 hours (seen anywhere)       (A1)

\n

eg   \nz\n=\n1.28155\n

\n

correct working to find \nσ\n       (A1)

\n

eg    \n1.28155\n=\n\n\n28\n\n25\n\nσ\n\n\n\n\n28\n\n25\n\n\n1.28155\n\n\n

\n

2.34091

\n

\nσ\n=\n2.34\n     A1  N2

\n

[3 marks]

\n
c.
\n
\n

\n\nP\n\n\n(\n\nX\n>\n30\n\n)\n\n=\n0.0163429\n       (A1)

\n

valid approach (seen anywhere)        (M1)

\n

eg   \n\n\n\n[\n\n\nP\n\n\n(\n\nX\n>\n30\n\n)\n\n\n]\n\n2\n\n\n ,  (0.01634)2 ,  B(2, 0.0163429) , 2.67E-4 , 2.66E-4

\n

0.0267090

\n

0.0267 %    A2  N3

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.2.SL.TZ2.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Emlyn plays many games of basketball for his school team. The number of minutes he plays in each game follows a normal distribution with mean m minutes.

\n

In any game there is a 30% chance he will play less than 13.6 minutes.

\n
\n

In any game there is a 70% chance he will play less than 17.8 minutes.

\n
\n

The standard deviation of the number of minutes Emlyn plays in any game is 4.

\n
\n

There is a 60% chance Emlyn plays less than x minutes in a game.

\n
\n

Emlyn will play in two basketball games today.

\n
\n

Emlyn and his teammate Johan each practise shooting the basketball multiple times from a point X. A record of their performance over the weekend is shown in the table below.

\n

\n

On Monday, Emlyn and Johan will practise and each will shoot 200 times from point X.

\n
\n

Sketch a diagram to represent this information.

\n
[2]
\n
a.
\n
\n

Show that m=15.7.

\n
[2]
\n
b.
\n
\n

Find the probability that Emlyn plays between 13 minutes and 18 minutes in a game.

\n
[2]
\n
c.i.
\n
\n

Find the probability that Emlyn plays more than 20 minutes in a game.

\n
[2]
\n
c.ii.
\n
\n

Find the value of x.

\n
[2]
\n
d.
\n
\n

Find the probability he plays between 13 minutes and 18 minutes in one game and more than 20 minutes in the other game.

\n
[3]
\n
e.
\n
\n

Find the expected number of successful shots Emlyn will make on Monday, based on the results from Saturday and Sunday.

\n
[2]
\n
f.
\n
\n

Emlyn claims the results from Saturday and Sunday show that his expected number of successful shots will be more than Johan’s.

\n

Determine if Emlyn’s claim is correct. Justify your reasoning.

\n
[2]
\n
g.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

         (A1)(A1)

\n


Note: Award (A1) for bell shaped curve with mean m or 13.6 indicated. Award (A1) for approximately correct shaded region.

\n


[2 marks]

\n
a.
\n
\n

PT>17.8=0.3         (M1)

\n


OR

\n

        (M1)

\n


Note: Award (M1) for correct probability equation using 0.3 OR correctly shaded diagram indicating 17.8. Strict or weak inequalities are accepted in parts (b), (c) and (d).

\n


13.6+17.82   17.8-17.8-13.62  OR  13.6+17.8-13.62         (M1)

\n


Note:
Award (M0)(M1) for unsupported 13.6+17.82 OR 17.8-17.8-13.62 OR 13.6+17.8-13.62 OR the midpoint of 13.6 and 17.8 is 15.7.
Award at most (M1)(M0) if the final answer is not seen. Award (M0)(M0) for using known values m=15.7 and σ=4 to validate PT<17.8=0.7 or PT<13.6=0.3.

\n


15.7         (AG)

\n


[2 marks]

\n
b.
\n
\n

P13T18         (M1)

\n


OR

\n

        (M1)

\n


Note: Award (M1) for correct probability equation OR correctly shaded diagram indicating 13 and 18.

\n


0.468  46.8%, 0.467516         (A1)(G2)

\n


[2 marks]

\n
c.i.
\n
\n

PT20         (M1)

\n


OR

\n

        (M1)

\n


Note: Award (M1) for correct probability equation OR correctly shaded diagram indicating 20.

\n


0.141  14.1%, 0.141187         (A1)(G2)

\n


[2 marks]

\n
c.ii.
\n
\n

PT<t=0.6         (M1)

\n


OR

\n

        (M1)

\n


Note: Award (M1) for correct probability equation OR for a correctly shaded region with x indicated to the right-hand side of the mean.

\n


16.7  16.7133         (A1)(G2)

\n


[2 marks]

\n
d.
\n
\n

0.467516×0.141187×2         (M1)(M1)

\n


OR

\n


0.467516×0.141187+0.141187×0.467516        (M1)(M1)

\n


Note: Award (M1) for the multiplication of their parts (c)(i) and (c)(ii), (M1) for multiplying their product by 2 or for adding their products twice. Follow through from part (c).

\n


0.132  13.2%, 0.132014         (A1)(ft)(G2)

\n


Note: Award (G0) for an unsupported final answer of 0.066007

\n


[3 marks]

\n
e.
\n
\n

69102×200         (M1)

\n


Note: Award (M1) for correct probability multiplied by 200.

\n


135  135.294         (A1)(G2)

\n


[2 marks]

\n
f.
\n
\n

6798×200= 136.734         (A1)

\n


Note: Award (M1) for 137 or 136.734 seen.

\n


Emlyn is incorrect, 135<137     135.294<136.734         (R1)

\n


Note:
To award the final (R1), both the conclusion and the comparison must be seen. Award at most (A0)(R1)(ft) for consistent incorrect methods in parts (f) and (g).

\n


OR

\n


6798= 0.684  0.683673     69102= 0.676  0.676470         (A1)

\n


Note: Award (A1) for both correct probabilities seen.

\n


Emlyn is incorrect, 0.676<0.684         (R1)

\n


Note:
 To award the final (R1), both the conclusion and the comparison must be seen. Award at most (A0)(R1)(ft) for consistent incorrect methods in parts (f) and (g).

\n


[2 marks]

\n
g.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
\n[N/A]\n
g.
\n
", "question_id": "20N.2.SL.TZ0.T_6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

In a group of 35 students, some take art class (A) and some take music class (M). 5 of these students do not take either class. This information is shown in the following Venn diagram.

\n

\n
\n

One student from the group is chosen at random. Find the probability that

\n
\n

Write down the number of students in the group who take art class.

\n
[2]
\n
a.
\n
\n

the student does not take art class.

\n
[2]
\n
b.i.
\n
\n

the student takes either art class or music class, but not both.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach      (M1)

\n

\n\n(\n\nA\n\n\nM\n\n\n\n)\n\n+\n\n(\n\nA\n\nM\n\n)\n\n,  \n\n\n17\n\n\n35\n\n\n,   11 + 6

\n

number of students taking art class = 17        A1 N2

\n

 

\n

[2 marks]

\n
a.
\n
\n

valid approach      (M1)

\n

13 + 5,   35 − 17,   18,   1 − P(A)

\n

0.514285

\n

P(A') = \n\n\n18\n\n\n35\n\n\n  (exact), 0.514         A1 N2

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

valid approach      (M1)

\n

11 + 13,   35 − 6 − 5,   24

\n

0.685714

\n

P(A or M but not both) = \n\n\n24\n\n\n35\n\n\n  (exact), 0.686         A1 N2

\n

 

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "18N.2.SL.TZ0.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-5-probability-concepts-expected-numbers" ] }, { "Question": "
\n

Find the term independent of x in the expansion of 1x313x2-x29.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

use of Binomial expansion to find a term in either 13x2-x29, 13x73-x2329, 13-x329, 13x3-129 or 2-3x39         (M1)(A1)

\n


Note: Award M1 for a product of three terms including a binomial coefficient and powers of the two terms, and A1 for a correct expression of a term in the expansion.

\n


finding the powers required to be 2 and 7         (M1)(A1)

\n

constant term is C29×132×-127         (M1)

\n


Note: Ignore all x’s in student’s expression.

therefore term independent of x is -132 =-0.03125       A1

\n


[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.2.AHL.TZ0.H_4", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Use mathematical induction to prove that dndxnxepx=pn-1px+nepx for n+, p.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

n=1: LHS=dxepxdx=xpepx+epx=px+1epx, RHS=p0px+1epx

\n

LHS=RHS so true for n=1:       A1

\n


Note: Award A1 if n=0 is proved.

\n


assume proposition true for n=k, i.e. dkdxkxepx=pk-1px+kepx       M1

\n


Notes: Do not award M1 if using n instead of k.
Assumption of truth must be present.
Subsequent marks are not dependent on this M1 mark.

\n


dk+1dxk+1xepx=ddxdkdxkxepx        (M1)

\n

=ddxpk-1px+kepx       M1

\n

=pk-1px+kpepx+epxpk

\n

=pkpx+kepx+epxpk       A1

\n


Note: Award A1 for correct derivative.

\n


=pkpx+k+1epx       A1

\n

=pk+1-1px+k+1epx

\n


Note: The final A1 can be awarded for either of the two lines above.

\n


hence true for n=1 and n=k true n=k+1 true       R1

\n

therefore true for all n+

\n


Note: Only award the final R1 if the three method marks have been awarded.

\n


[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.2.AHL.TZ0.H_6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

At a gathering of 12 teachers, seven are male and five are female. A group of five of these teachers go out for a meal together. Determine the possible number of groups in each of the following situations:

\n
\n

There are more males than females in the group.

\n
[4]
\n
a.
\n
\n

Two of the teachers, Gary and Gerwyn, refuse to go out for a meal together.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

identifying two or three possible cases        (M1)

\n

total number of possible groups is 75+7451+7352        (A1)(A1)

\n


Note: Award A1 for any two correct cases, A1 for the other one.

\n


=21+35×5+35×10

\n

=546       A1

\n


[4 marks]

\n
a.
\n
\n

METHOD 1

\n

identifying at least two of the three possible cases- Gary goes, Gerwyn goes or neither goes        (M1)

\n

total number of possible groups is 105+104+104        (A1)

\n

=252+210+210

\n

=672       A1

\n

 

\n

METHOD 2

\n

identifying the overall number of groups and no. of cases where both Gary and Gerwyn go.        (M1)

\n

total number of possible groups is 125-103        (A1)

\n

=792-120

\n

=672       A1

\n


[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.2.AHL.TZ0.H_7", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

The following Venn diagram shows the events \nA\n and \nB\n, where \n\nP\n\n\n(\nA\n)\n\n=\n0.3\n. The values shown are probabilities.

\n

\n
\n

Find the value of p .

\n
[2]
\n
a.
\n
\n

Find the value of q .

\n
[2]
\n
b.
\n
\n

Find P ( A B ) .

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

valid approach        (M1)

\n

eg      0.30 − 0.1, p + 0.1 = 0.3

\n

p  = 0.2        A1 N2

\n

[2 marks]

\n
a.
\n
\n

valid approach        (M1)

\n

eg     1 − (0.3 + 0.4), 1 − 0.4 − 0.1 −  p

\n

q  = 0.3        A1 N2

\n

[2 marks]

\n
b.
\n
\n

valid approach        (M1)

\n

eg      0.7 + 0.5 0.3 p + q + 0.4 1 0.1 ,   P ( A B ) = P ( A ) + P ( B ) P ( A B )

\n

\n

P ( A B ) = 0.9        A1 N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.1.SL.TZ1.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A small bead is free to move along a smooth wire in the shape of the curve y=103-2e-0.5xx0.

\n
\n

Find an expression for dydx.

\n
[3]
\n
a.
\n
\n

At the point on the curve where x=4, it is given that dydt=-0.1m s-1

\n

Find the value of dxdt at this exact same instant.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid attempt to use chain rule or quotient rule       (M1)

\n

dydx=-10e-0.5x3-2e-0.5x2  OR   dydx=-10e-0.5x3-2e-0.5x-2      A1A1

\n


[3 marks]

\n


Note: Award A1 for numerator and A1 for denominator, or A1 for each part if the second alternative given.

\n
a.
\n
\n

valid attempt to use chain rule eg  dydt=dydx×dxdt      (M1)

\n

dxdt=-0.1÷-10e-23-2e-22 =-0.1÷-0.181676  or equivalent      (A1)

\n

=0.550428

\n

dxdt=0.550 ms-1       A1

\n


[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.2.AHL.TZ0.H_8", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

Events \nA\n and \nB\n are independent with \n\nP\n\n(\nA\n\nB\n)\n=\n0.2\n and \n\nP\n\n(\n\nA\n\n\n\nB\n)\n=\n0.6\n.

\n
\n

Find P ( B ) .

\n
[2]
\n
a.
\n
\n

Find P ( A B ) .

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

valid interpretation (may be seen on a Venn diagram)     (M1)

\n

eg P ( A B ) + P ( A B ) ,   0.2 + 0.6

\n

P ( B ) = 0.8      A1     N2

\n

[2 marks]

\n
a.
\n
\n

valid attempt to find P ( A )      (M1)

\n

eg P ( A B ) = P ( A ) × P ( B ) ,   0.8 × A = 0.2

\n

correct working for P ( A )      (A1)

\n

eg 0.25 ,   0.2 0.8

\n

correct working for P ( A B )      (A1)

\n

eg 0.25 + 0.8 0.2 ,   0.6 + 0.2 + 0.05

\n

P ( A B ) = 0.85      A1     N3

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.1.SL.TZ0.S_5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

The nth term of an arithmetic sequence is given by un=15-3n.

\n
\n

State the value of the first term, u1.

\n
[1]
\n
a.
\n
\n

Given that the nth term of this sequence is -33, find the value of n.

\n
[2]
\n
b.
\n
\n

Find the common difference, d.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

u1=12          A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

15-3n=-33           (A1)

\n

n=16           A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

valid approach to find d          (M1)

\n

u2-u1=9-12  OR  recognize gradient is 3  OR  attempts to solve -33=12+15d

\n

d=-3           A1

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n

A large majority of candidates earned full marks for this question. In part (a), a surprising number of candidates did not substitute n=1 into the given expression, erroneously stating u1=15. Many of these candidates were able to earn follow-through marks in later parts of the question. In part (b), algebraic errors led a few candidates to find inappropriate values for n, such as n=-6.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.1.SL.TZ2.2", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

The weights, in grams, of individual packets of coffee can be modelled by a normal distribution, with mean 102g and standard deviation 8g.

\n
\n

Find the probability that a randomly selected packet has a weight less than 100g.

\n
[2]
\n
a.
\n
\n

The probability that a randomly selected packet has a weight greater than w grams is 0.444. Find the value of w.

\n
[2]
\n
b.
\n
\n

A packet is randomly selected. Given that the packet has a weight greater than 105g, find the probability that it has a weight greater than 110g.

\n
[3]
\n
c.
\n
\n

From a random sample of 500 packets, determine the number of packets that would be expected to have a weight lying within 1.5 standard deviations of the mean.

\n
[3]
\n
d.
\n
\n

Packets are delivered to supermarkets in batches of 80. Determine the probability that at least 20 packets from a randomly selected batch have a weight less than 95g.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

Χ~N102, 82

\n

PΧ<100=0.401        (M1)A1

\n


[2 marks]

\n
a.
\n
\n

PΧ>w=0.444       (M1)

\n

w=103 g        A1

\n


[2 marks]

\n
b.
\n
\n

PΧ>100Χ>105=PΧ>100Χ>105PΧ>105       (M1)

\n

=PΧ>100PΧ>105        (A1)

\n

=0.158650.35383

\n

=0.448       A1

\n


[3 marks]

\n
c.
\n
\n

EITHER

\n


P90<Χ<114=0.866        (A1)

\n


OR

\n


P-1.5<Z<1.5=0.866        (A1)

\n


THEN

\n


0.866×500       (M1)

\n

=433         A1

\n


[3 marks]

\n
d.
\n
\n

p=PΧ<95=0.19078         (A1)

\n

recognising  Y~B80, p        (M1)

\n

now using  Y~B80, 0.19078        (M1)

\n

PY20=0.116          A1

\n


[4 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "20N.2.AHL.TZ0.H_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

A function f is defined by fx=2x-1x+1, where x, x-1.

\n
\n

The graph of y=f(x) has a vertical asymptote and a horizontal asymptote.

\n
\n

Write down the equation of the vertical asymptote.

\n
[1]
\n
a.i.
\n
\n

Write down the equation of the horizontal asymptote.

\n
[1]
\n
a.ii.
\n
\n

On the set of axes below, sketch the graph of y=f(x).

\n

On your sketch, clearly indicate the asymptotes and the position of any points of intersection with the axes.

\n

\n
[3]
\n
b.
\n
\n

Hence, solve the inequality 0<2x-1x+1<2.

\n
[1]
\n
c.
\n
", "Markscheme": "
\n

x=-1          A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

y=2          A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

\n

 

\n

rational function shape with two branches in opposite quadrants, with two correctly positioned asymptotes and asymptotic behaviour shown         A1

\n

 

\n

Note: The equations of the asymptotes are not required on the graph provided there is a clear indication of asymptotic behaviour at x=-1 and y=2 (or at their FT asymptotes from part (a)).

\n

 

\n

axes intercepts clearly shown at x=12 and y=-1         A1A1

\n

 

\n

[3 marks]

\n
b.
\n
\n

x>12         A1

\n

 

\n

Note: Accept correct alternative correct notation, such as 12,  and ]12,[.

\n

 

\n

[1 mark]

\n
c.
\n
", "Examiners report": "
\n

It is pleasing to note that many candidates were familiar with the shape of the graph of a rational function of the form f(x)=ax+bcx+d, and a large number of them were able to sketch an appropriate graph. Part (c) was a struggle for the majority of candidates, with only a few answering correctly. Despite the word \"hence\" and the single mark available in this part, most candidates who attempted part (c) did so by trying to solve the inequality algebraically, rather than seeing the connection to the values in their graph.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.1.SL.TZ2.4", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing" ] }, { "Question": "
\n

Consider any three consecutive integers, n-1, n and n+1.

\n
\n

Prove that the sum of these three integers is always divisible by 3.

\n
[2]
\n
a.
\n
\n

Prove that the sum of the squares of these three integers is never divisible by 3.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

n-1+n+n+1          (A1)

\n

=3n           A1

\n

which is always divisible by 3           AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

n-12+n2+n+12   =n2-2n+1+n2+n2+2n+1           A1

\n

attempts to expand either n-12 or n+12    (do not accept n2-1 or n2+1)          (M1)

\n

=3n2+2           A1

\n

demonstrating recognition that 2 is not divisible by 3 or 23 seen after correct expression divided by 3            R1

\n

 

\n

3n2 is divisible by 3 and so 3n2+2 is never divisible by 3

\n

OR  the first term is divisible by 3, the second is not

\n

OR  3n2+23  OR  3n2+23=n2+23

\n

hence the sum of the squares is never divisible by 3          AG

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n

Most candidates were able to earn full marks in part (a), though some were not able to provide the required reasoning to earn full marks in part (b). In many cases, candidates did not seem to understand the nature of a general deductive proof, and instead substituted different consecutive integers (such as 1, 2,3 ), showing the desired result for these specific values, rather than an algebraic generalization for any three consecutive integers.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.SL.TZ2.3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-6-simple-proof" ] }, { "Question": "
\n

A discrete random variable \nX\n has the following probability distribution.

\n

\"N17/5/MATME/SP2/ENG/TZ0/04\"

\n
\n

Find the value of \nk\n.

\n
[4]
\n
a.
\n
\n

Write down \n\nP\n\n(\nX\n=\n2\n)\n.

\n
[1]
\n
b.
\n
\n

Find \n\nP\n\n(\nX\n=\n2\n\n|\n\nX\n>\n0\n)\n.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)

\n

eg\n\n\n\n\n\ntotal probability = 1

\n

correct equation     (A1)

\n

eg\n\n\n\n\n\n\n0.475\n+\n2\n\n\nk\n2\n\n\n+\n\nk\n\n10\n\n\n+\n6\n\n\nk\n2\n\n\n=\n1\n,\n\n \n\n8\n\n\nk\n2\n\n\n+\n0.1\nk\n\n0.525\n=\n0\n

\n

\nk\n=\n0.25\n     A2     N3

\n

[4 marks]

\n
a.
\n
\n

\n\nP\n\n(\nX\n=\n2\n)\n=\n0.025\n     A1     N1

\n

[1 mark]

\n
b.
\n
\n

valid approach for finding \n\nP\n\n(\nX\n>\n0\n)\n     (M1)

\n

eg\n\n\n\n\n\n\n1\n\n0.475\n,\n\n \n\n2\n(\n\n\n0.25\n2\n\n\n)\n+\n0.025\n+\n6\n(\n\n\n0.25\n2\n\n\n)\n,\n\n \n\n1\n\n\nP\n\n(\nX\n=\n0\n)\n,\n\n \n\n2\n\n\nk\n2\n\n\n+\n\nk\n\n10\n\n\n+\n6\n\n\nk\n2\n\n\n

\n

correct substitution into formula for conditional probability     (A1)

\n

eg\n\n\n\n\n\n\n\n\n0.025\n\n\n1\n\n0.475\n\n\n,\n\n \n\n\n\n0.025\n\n\n0.525\n\n\n

\n

0.0476190

\n

\n\nP\n\n(\nX\n=\n2\n\n|\n\nX\n>\n0\n)\n=\n\n1\n\n21\n\n\n (exact), 0.0476     A1     N2

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17N.2.SL.TZ0.S_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Find the least positive value of x for which cosx2+π3=12.

\n
", "Markscheme": "
\n

determines π4 (or 45°) as the first quadrant (reference) angle           (A1)

\n

attempts to solve x2+π3=π4           (M1)

\n

 

\n

Note: Award M1 for attempting to solve x2+π3=π4,7π4,

\n

 

\n

x2+π3=π4x<0 and so π4 is rejected           (R1)

\n

x2+π3=2π-π4 =7π4           A1

\n

x=17π6  (must be in radians)           A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n

This question proved to be a struggle for many candidates, and some candidates made no attempt here. While a good number of candidates recognized the reference angle of π4, this led to a final answer of x=-π6, which many left as their final answer. In other cases, some candidates heeded the requirement that x must be a positive value, however they gave an incorrect final answer of x=11π6. Few candidates correctly rejected their initial reference angle of π4 and correctly solved an equation using x2+π3=7π4.

\n
", "question_id": "22M.1.SL.TZ2.5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule" ] }, { "Question": "
\n

The following diagram shows part of the graph of a quadratic function f.

\n

The graph of f has its vertex at (3, 4), and it passes through point Q as shown.

\n

\n
\n

The function can be written in the form f(x)=a(x-h)2+k.

\n
\n

The line L is tangent to the graph of f at Q.

\n
\n

Now consider another function y=g(x). The derivative of g is given by g(x)=f(x)-d, where d.

\n
\n

Write down the equation of the axis of symmetry.

\n
[1]
\n
a.
\n
\n

Write down the values of h and k.

\n
[2]
\n
b.i.
\n
\n

Point Q has coordinates (5, 12). Find the value of a.

\n
[2]
\n
b.ii.
\n
\n

Find the equation of L.

\n
[4]
\n
c.
\n
\n

Find the values of d for which g is an increasing function.

\n
[3]
\n
d.
\n
\n

Find the values of x for which the graph of g is concave-up.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

x=3            A1

\n

 

\n

Note: Must be an equation in the form “ x= ”. Do not accept 3 or -b2a=3.

\n

 

\n

[1 mark]

\n
a.
\n
\n

h=3, k=4   (accept ax-32+4)            A1A1

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

attempt to substitute coordinates of Q             (M1)

\n

12=a5-32+4,  4a+4=12

\n

a=2             A1

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

recognize need to find derivative of f            (M1)

\n

f'x=4x-3  or  f'x=4x-12             A1

\n

f'5=8  (may be seen as gradient in their equation)            (A1)

\n

y-12=8x-5  or  y=8x-28             A1

\n

 

\n

Note: Award A0 for L=8x28.

\n

 

\n

[4 marks]

\n
c.
\n
\n

METHOD 1

\n

Recognizing that for g to be increasing, fx-d>0, or g'>0          (M1)

\n

The vertex must be above the x-axis, 4-d>0, d-4<0          (R1)

\n

d<4             A1

\n

 

\n

METHOD 2

\n

attempting to find discriminant of g'          (M1)

\n

-122-4222-d

\n

recognizing discriminant must be negative          (R1)

\n

-32+8d<0   OR  Δ<0

\n

d<4             A1

\n

 

\n

[3 marks]

\n
d.
\n
\n

recognizing that for g to be concave up, g''>0          (M1)

\n

g''>0 when f'>0, 4x-12>0, x-3>0          (R1)

\n

x>3          A1

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n

In parts (a) and (b) of this question, a majority of candidates recognized the connection between the coordinates of the vertex and the axis of symmetry and the values of h and k, and most candidates were able to successfully substitute the coordinates of point Q to find the value of a. In part (c), the candidates who recognized the need to use the derivative to find the gradient of the tangent were generally successful in finding the equation of the line, although many did not give their equation in the proper form in terms of x and y, and instead wrote L=8x-28, thus losing the final mark. Parts (d) and (e) were much more challenging for candidates. Although a good number of candidates recognized that g'(x)>0 in part (d), and g''(x)>0 in part (e), very few were able to proceed beyond this point and find the correct inequalities for their final answers.

\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "22M.1.SL.TZ2.7", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-6-quadratic-function", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion", "sl-2-1-equations-of-straight-lines-parallel-and-perpendicular", "sl-5-2-increasing-and-decreasing-functions" ] }, { "Question": "
\n

Consider the binomial expansion (x+1)7=x7+ax6+bx5+35x4++1 where x0 and a, b+.

\n
\n

Show that b=21.

\n
[2]
\n
a.
\n
\n

The third term in the expansion is the mean of the second term and the fourth term in the expansion.

\n

Find the possible values of x.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

EITHER

\n

recognises the required term (or coefficient) in the expansion           (M1)

\n

bx5=C27x512   OR   b=C27  OR  C57

\n

b=7!2!5! =7!2!7-2!

\n

correct working           A1

\n

7×6×5×4×3×2×12×1×5×4×3×2×1   OR   7×62!   OR   422

\n


OR

\n

lists terms from row 7 of Pascal’s triangle           (M1)

\n

1, 7, 21,           A1

\n


THEN

\n

b=21           AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

a=7            (A1)

\n

correct equation            A1

\n

21x5=ax6+35x42   OR   21x5=7x6+35x42

\n

correct quadratic equation            A1

\n

7x2-42x+35=0  OR  x2-6x+5=0  (or equivalent)

\n

valid attempt to solve their quadratic            (M1)

\n

x-1x-5=0   OR   x=6±-62-41521

\n

x=1, x=5            A1

\n

 

\n

Note: Award final A0 for obtaining x=0, x=1, x=5.

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n

The majority of candidates answered part (a) correctly, either by using the Crn formula or Pascal's Triangle. In part (b) of the question, most candidates were able to correctly find the value of a=7 and set up a correct equation showing the mean of the second and fourth terms. While some struggled to complete the required algebra to solve the equation, the majority of candidates who found a correct quadratic equation were able to solve it correctly. A few candidates included x=0 in their final answer, thus not earning the final mark.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.SL.TZ2.6", "topics": [ "topic-1-number-and-algebra", "topic-2-functions" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer", "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

A biased four-sided die with faces labelled 1, 2, 3 and 4 is rolled and the result recorded. Let X be the result obtained when the die is rolled. The probability distribution for X is given in the following table where p and q are constants.

\n

\n

For this probability distribution, it is known that E(X)=2.

\n
\n

Nicky plays a game with this four-sided die. In this game she is allowed a maximum of five rolls. Her score is calculated by adding the results of each roll. Nicky wins the game if her score is at least ten.

\n

After three rolls of the die, Nicky has a score of four.

\n
\n

David has two pairs of unbiased four-sided dice, a yellow pair and a red pair.

\n

Both yellow dice have faces labelled 1, 2, 3 and 4. Let S represent the sum obtained by rolling the two yellow dice. The probability distribution for S is shown below.

\n

\n

The first red die has faces labelled 1, 2, 2 and 3. The second red die has faces labelled 1, a, a and b, where a<b and a, b+. The probability distribution for the sum obtained by rolling the red pair is the same as the distribution for the sum obtained by rolling the yellow pair.

\n
\n

Show that p=0.4 and q=0.2.

\n
[5]
\n
a.
\n
\n

Find P(X>2).

\n
[2]
\n
b.
\n
\n

Assuming that rolls of the die are independent, find the probability that Nicky wins the game.

\n
[5]
\n
c.
\n
\n

Determine the value of b.

\n
[2]
\n
d.
\n
\n

Find the value of a, providing evidence for your answer.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

uses PX=x=1 to form a linear equation in p and q           (M1)

\n

correct equation in terms of p and q from summing to 1          A1

\n

p+0.3+q+0.1=1  OR  p+q=0.6  (or equivalent)

\n

uses EX=2 to form a linear equation in p and q           (M1)

\n

correct equation in terms of p and q from EX=2          A1

\n

p+0.6+3q+0.4=2  OR  p+3q=1  (or equivalent)

\n

 

\n

Note: The marks for using PX=x=1 and the marks for using EX=2 may be awarded independently of each other.

\n

 

\n

evidence of correctly solving these equations simultaneously          A1

\n

for example, 2q=0.4q=0.2  or  p+3×0.6-p=1p=0.4

\n

so p=0.4 and q=0.2          AG

\n

 

\n

[5 marks]

\n
a.
\n
\n

valid approach        (M1)

\n

P(X>2)=P(X=3)+P(X=4)  OR  P(X>2)=1-P(X=1)-P(X=2)

\n

=0.3          A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

recognises at least one of the valid scores (6, 7, or 8) required to win the game           (M1)

\n

 

\n

Note: Award M0 if candidate also considers scores other than 6, 7, or 8 (such as 5).

\n

 

\n

let T represent the score on the last two rolls

\n

a score of 6 is obtained by rolling 2,4, 4,2 or 3,3

\n

PT=6=20.30.1+0.22  =0.1          A1

\n

a score of 7 is obtained by rolling 3,4 or 4,3

\n

PT=7=20.20.1  =0.04          A1

\n

a score of 8 is obtained by rolling 4,4

\n

PT=8=0.12  =0.01          A1

\n

 

\n

Note: The above 3 A1 marks are independent of each other.

\n

 

\n

P(Nicky wins)=0.1+0.04+0.01

\n

=0.15          A1

\n

 

\n

[5 marks]

\n
c.
\n
\n

3+b=8           (M1)

\n

b=5          A1 

\n

 

\n

[2 marks]

\n
d.
\n
\n

METHOD 1

\n

EITHER

\n

PS=5=416

\n

PS=a+2=416          A1 

\n

a+2=5

\n


OR

\n

PS=6=316

\n

PS=a+3=216  and  PS=5+1=116          A1 

\n

a+3=6

\n


OR

\n

PS=4=316

\n

PS=a+1=216  and  PS=1+3=116          A1 

\n

a+1=4

\n


THEN

\n

a=3          A1 

\n

 

\n

Note: Award A0A0 for a=3 obtained without working/reasoning/justification.

\n

 

\n

METHOD 2

\n

EITHER

\n

correctly lists a relevant part of the sample space          A1 

\n

for example, S=4=3,1,1,a,1,a  or  S=5=2,a,2,a,2,a,2,a

\n

or S=6=3,a,3,a,1,5

\n

a+3=6

\n


OR

\n

eliminates possibilities (exhaustion) for a<5

\n

convincingly shows that a2,4          A1 

\n

a4, for example, PS=7=216 from 2,5,2,5 and so

\n

3,a,3,aa+37

\n

 

\n

THEN

\n

a=3          A1 

\n

 

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n

A majority of candidates knew to set up equations using the sum of the probabilities in the distribution equal to 1 and/or the expected value equal to 2, however some candidates simply substituted the given values of p and q into their equations, which is considered working backwards and not doing what is required by the command term \"show that\". For the candidates who did set up both equations in terms of p and q, nearly all were successful in solving the resulting system of equations. Many candidates answered part (b) correctly using the given values from part (a). In part (c), most candidates recognized a sum of 6 (or more) was required in the final two rolls, but very few were able to find all the different outcomes to make this happen, especially for sums that can happen in more than one way, such as 3+4 and 4+3. While some candidates were able to correctly answer parts (d) and (e), some did not attempt
these questions parts, and many did not justify their final answer in part (e).

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "22M.1.SL.TZ2.9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables", "sl-4-5-probability-concepts-expected-numbers" ] }, { "Question": "
\n

Use l’Hôpital’s rule to find

\n

limx1cosx2-1-1ex-1-x.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

attempt to use l’Hôpital’s rule        M1

\n

=limx1-2xsinx2-1ex-1-1       A1A1

\n


Note: Award A1 for the numerator and A1 for the denominator.

\n


substitution of 1 into their expression        (M1)

\n

=00 hence use l’Hôpital’s rule again

\n


Note: If the first use of l’Hôpital’s rule results in an expression which is not in indeterminate form, do not award any further marks.

\n


attempt to use product rule in numerator       M1

\n

=limx1-4x2cosx2-1-2sinx2-1ex-1       A1

\n

=-4       A1

\n


[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "20N.3.AHL.TZ0.HCA_1", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

The weights, in grams, of oranges grown in an orchard, are normally distributed with a mean of 297 g. It is known that 79 % of the oranges weigh more than 289 g and 9.5 % of the oranges weigh more than 310 g.

\n
\n

The weights of the oranges have a standard deviation of σ.

\n
\n

The grocer at a local grocery store will buy the oranges whose weights exceed the 35th percentile.

\n
\n

The orchard packs oranges in boxes of 36.

\n
\n

Find the probability that an orange weighs between 289 g and 310 g.

\n
[2]
\n
a.
\n
\n

Find the standardized value for 289 g.

\n
[2]
\n
b.i.
\n
\n

Hence, find the value of σ.

\n
[3]
\n
b.ii.
\n
\n

To the nearest gram, find the minimum weight of an orange that the grocer will buy.

\n
[3]
\n
c.
\n
\n

Find the probability that the grocer buys more than half the oranges in a box selected at random.

\n
[5]
\n
d.
\n
\n

The grocer selects two boxes at random.

\n

Find the probability that the grocer buys more than half the oranges in each box.

\n
[2]
\n
e.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct approach indicating subtraction      (A1)

\n

eg  0.79 − 0.095, appropriate shading in diagram

\n

P(289 < w < 310) = 0.695 (exact), 69.5 %      A1 N2

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

valid approach      (M1)

\n

eg    1 − p, 21

\n

−0.806421

\n

z = −0.806      A1 N2

\n

 

\n

METHOD 2

\n

(i) & (ii)

\n

correct expression for z (seen anywhere)   (A1)

\n

eg  \n\n\n289\n\nu\n\nσ\n\n

\n

valid approach      (M1)

\n

eg    1 − p, 21

\n

−0.806421

\n

z = −0.806 (seen anywhere)      A1 N2

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

METHOD 1

\n

attempt to standardize     (M1)

\n

eg    \nσ\n=\n\n\n289\n\n297\n\nz\n\n,\n\n\n\n\n289\n\n297\n\nσ\n\n

\n

correct substitution with their z (do not accept a probability)     A1

\n

eg  \n\n0.806\n=\n\n\n289\n\n297\n\nσ\n\n,\n\n\n\n\n289\n\n297\n\n\n\n0.806\n\n\n

\n

9.92037

\n

σ = 9.92      A1 N2

\n

 

\n

METHOD 2

\n

(i) & (ii)

\n

correct expression for z (seen anywhere)   (A1)

\n

eg  \n\n\n289\n\nu\n\nσ\n\n

\n

valid approach      (M1)

\n

eg    1 − p, 21

\n

−0.806421

\n

z = −0.806 (seen anywhere)      A1 N2

\n

valid attempt to set up an equation with their z (do not accept a probability)     (M1)

\n

eg  \n\n0.806\n=\n\n\n289\n\n297\n\nσ\n\n,\n\n\n\n\n289\n\n297\n\n\n\n0.806\n\n\n

\n

9.92037

\n

σ = 9.92      A1 N2

\n

[3 marks]

\n
b.ii.
\n
\n

valid approach      (M1)

\n

eg  P(W < w) = 0.35, −0.338520 (accept 0.385320), diagram showing values in a standard normal distribution

\n

correct score at the 35th percentile      (A1)

\n

eg  293.177

\n

294 (g)       A1 N2

\n

Note: If working shown, award (M1)(A1)A0 for 293.
If no working shown, award N1 for 293.177, N1 for 293.

\n

Exception to the FT rule: If the score is incorrect, and working shown, award A1FT for correctly finding their minimum weight (by rounding up)

\n

[3 marks]

\n
c.
\n
\n

evidence of recognizing binomial (seen anywhere)     (M1)

\n

eg  \nX\n\n\nB\n\n\n(\n\n36\n,\n\n\np\n\n)\n\n,\n\n\n\n\n\nn\n\n\n\nC\na\n\n\n×\n\n\np\na\n\n\n×\n\n\nq\n\nn\n\na\n\n\n\n

\n

correct probability (seen anywhere) (A1)

\n

eg 0.65

\n

EITHER

\n

finding P(X ≤ 18) from GDC     (A1)

\n

eg 0.045720

\n

evidence of using complement      (M1)

\n

eg 1−P(X ≤ 18)

\n

0.954279

\n

P(X > 18) = 0.954     A1  N2

\n

OR

\n

recognizing P(X > 18) = P(X ≥ 19)     (M1)

\n

summing terms from 19 to 36      (A1)

\n

eg  P(X = 19) + P(X = 20) + … + P(X = 36)

\n

0.954279

\n

P(X > 18) = 0.954     A1  N2

\n

[5 marks]

\n
d.
\n
\n

correct calculation      (A1)

\n

\n\n\n0.954\n2\n\n\n,\n\n\n\n(\n\n\n\n2\n\n\n\n\n2\n\n\n\n)\n\n\n\n0.954\n2\n\n\n\n\n\n(\n\n1\n\n0.954\n\n)\n\n0\n\n\n

\n

0.910650

\n

0.911      A1 N2

\n

[2 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "18M.2.SL.TZ1.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Consider the functions fx=1x-4+1, for x4, and gx=x-3 for x.

\n

The following diagram shows the graphs of f and g.

\n

\n

The graphs of f and g intersect at points A and B. The coordinates of A are (3, 0).

\n
\n

In the following diagram, the shaded region is enclosed by the graph of f, the graph of g, the x-axis, and the line x=k, where k.

\n

\n

The area of the shaded region can be written as ln(p)+8, where p.

\n
\n

Find the coordinates of B.

\n
[5]
\n
a.
\n
\n

Find the value of k and the value of p.

\n
[10]
\n
b.
\n
", "Markscheme": "
\n

1x-4+1=x-3           (M1)

\n

x2-8x+15=0  OR  x-42=1           (A1)

\n

valid attempt to solve their quadratic           (M1)

\n

x-3x-5=0  OR  x=8±82-411521  OR  x-4=±1

\n

x=5  x=3, x=5 (may be seen in answer)          A1

\n

B5, 2  (accept x=5, y=2)          A1

\n

 

\n

[5 marks]

\n
a.
\n
\n

recognizing two correct regions from x=3 to x=5 and from x=5 to x=k           (R1)

\n

triangle +5kfxdx  OR  35gxdx+5kfxdx  OR  35x-3dx+5k1x-4+1dx

\n

area of triangle is 2  OR  2·22  OR  522-35-322-33           (A1)

\n

correct integration           (A1)(A1)

\n

1x-4+1dx=lnx-4+x +C

\n

 

\n

Note: Award A1 for lnx-4 and A1 for x.
Note: The first three A marks may be awarded independently of the R mark.

\n

 

\n

substitution of their limits (for x) into their integrated function (in terms of x)           (M1)

\n

lnk-4+k-ln1+5

\n

lnx-4+x5k=lnk-4+k-5          A1

\n

adding their two areas (in terms of k) and equating to lnp+8           (M1)

\n

2+lnk-4+k-5=lnp+8

\n

equating their non-log terms to 8 (equation must be in terms of k)           (M1)

\n

k-3=8

\n

k=11          A1

\n

11-4=p

\n

p=7          A1

\n

 

\n

[10 marks]

\n
b.
\n
", "Examiners report": "
\n

Nearly all candidates knew to set up an equation with f(x)=g(x) in order to find the intersection of the two graphs, and most were able to solve the resulting quadratic equation. Candidates were not as successful in part (b), however. While some candidates recognized that there were two regions to be added together, very few were able to determine the correct boundaries of these regions, with many candidates integrating one or both functions from x=3to x=k. While a good number of candidates were able to correctly integrate the function(s), without the correct bounds the values of k and p were unattainable.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.SL.TZ2.8", "topics": [ "topic-2-functions", "topic-1-number-and-algebra" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-1-5-intro-to-logs" ] }, { "Question": "
\n

A random variable \nX\n is normally distributed with mean, \nμ\n. In the following diagram, the shaded region between 9 and \nμ\n represents 30% of the distribution.

\n

\"M17/5/MATME/SP2/ENG/TZ1/09\"

\n
\n

The standard deviation of \nX\n is 2.1.

\n
\n

The random variable \nY\n is normally distributed with mean \nλ\n and standard deviation 3.5. The events \nX\n>\n9\n and \nY\n>\n9\n are independent, and \nP\n\n(\n\n(\nX\n>\n9\n)\n\n(\nY\n>\n9\n)\n\n)\n\n=\n0.4\n.

\n
\n

Find \n\nP\n\n(\nX\n<\n9\n)\n.

\n
[2]
\n
a.
\n
\n

Find the value of \nμ\n.

\n
[3]
\n
b.
\n
\n

Find \nλ\n.

\n
[5]
\n
c.
\n
\n

Given that \nY\n>\n9\n, find \n\nP\n\n(\nY\n<\n13\n)\n.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\nP\n\n(\nX\n<\nμ\n)\n=\n0.5\n,\n\n \n\n0.5\n\n0.3\n

\n

\n\nP\n\n(\nX\n<\n9\n)\n=\n0.2\n (exact)     A1     N2

\n

[2 marks]

\n
a.
\n
\n

\nz\n=\n\n0.841621\n (may be seen in equation)     (A1)

\n

valid attempt to set up an equation with their \nz\n     (M1)

\n

eg\n\n\n\n\n\n\n\n0.842\n=\n\n\nμ\n\nX\n\nσ\n\n,\n\n \n\n\n0.842\n=\n\n\nX\n\nμ\n\nσ\n\n,\n\n \n\nz\n=\n\n\n9\n\nμ\n\n\n2.1\n\n\n

\n

10.7674

\n

\nμ\n=\n10.8\n     A1     N3

\n

[3 marks]

\n
b.
\n
\n

\n\nP\n\n(\nX\n>\n9\n)\n=\n0.8\n (seen anywhere)     (A1)

\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\nP\n\n(\nA\n)\n×\n\nP\n\n(\nB\n)\n

\n

correct equation     (A1)

\n

eg\n\n\n\n\n\n\n0.8\n×\n\nP\n\n(\nY\n>\n9\n)\n=\n0.4\n

\n

\n\nP\n\n(\nY\n>\n9\n)\n=\n0.5\n     A1

\n

\nλ\n=\n9\n     A1     N3

\n

[5 marks]

\n
c.
\n
\n

finding \n\nP\n\n(\n9\n<\nY\n<\n13\n)\n=\n0.373450\n (seen anywhere)     (A2)

\n

recognizing conditional probability     (M1)

\n

eg\n\n\n\n\n\n\n\nP\n\n(\nA\n\n|\n\nB\n)\n,\n\n P\n\n(\nY\n<\n13\n\n|\n\nY\n>\n9\n)\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n\n\n\n0.373\n\n\n\n0.5\n\n\n

\n

0.746901

\n

0.747     A1     N3

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "17M.2.SL.TZ1.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A random variable Z is normally distributed with mean 0 and standard deviation 1. It is known that P(\nz\n < −1.6) = \na\n and P(\nz\n > 2.4) = \nb\n. This is shown in the following diagram.

\n

\n
\n

A second random variable \nX\n is normally distributed with mean \nm\n and standard deviation \ns\n.

\n

It is known that P(\nx\n < 1) = \na\n.

\n
\n

Find P(−1.6 < \nz\n < 2.4). Write your answer in terms of \na\n and \nb\n.

\n
[2]
\n
a.
\n
\n

Given that \nz\n > −1.6, find the probability that z < 2.4 . Write your answer in terms of \na\n and \nb\n.

\n
[4]
\n
b.
\n
\n

Write down the standardized value for \nx\n=\n1\n.

\n
[1]
\n
c.
\n
\n

It is also known that P(\nx\n > 2) = \nb\n.

\n

Find \ns\n.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognizing area under curve = 1        (M1)

\n

eg   \na\n+\nx\n+\nb\n=\n1\n,  \n100\n\na\n\nb\n,  \n1\n\na\n+\nb\n

\n

\n\nP\n\n\n(\n\n\n1.6\n<\nz\n<\n2.4\n\n)\n\n=\n1\n\na\n\nb\n\n\n\n(\n\n=\n1\n\n\n(\n\na\n+\nb\n\n)\n\n\n)\n\n               A1  N2

\n

[2 marks]

\n
a.
\n
\n

\n\nP\n\n\n(\n\nz\n>\n\n1.6\n\n)\n\n=\n1\n\na\n (seen anywhere)        (A1)

\n

recognizing conditional probability        (M1)

\n

eg   \n\nP\n\n\n(\n\nA\n\n|\nB\n\n\n\n)\n\n,  \n\nP\n\n\n(\n\nB\n\n|\nA\n\n\n\n)\n\n

\n

correct working       (A1)

\n

eg   \n\n\n\nP\n\n\n(\n\nz\n<\n2.4\n\nz\n>\n\n1.6\n\n)\n\n\n\n\nP\n\n\n(\n\nz\n>\n\n1.6\n\n)\n\n\n\n\n\n\n\nP\n\n\n(\n\n\n1.6\n<\nz\n<\n2.4\n\n)\n\n\n\n\nP\n\n\n(\n\nz\n>\n\n1.6\n\n)\n\n\n\n 

\n

\n\nP\n\n\n(\n\nz\n<\n2.4\n\n|\nz\n\n\n>\n\n1.6\n\n)\n\n=\n\n\n1\n\na\n\nb\n\n\n1\n\na\n\n\n      A1  N4

\n

Note: Do not award the final A1 if correct answer is seen followed by incorrect simplification.

\n

[4 marks]

\n
b.
\n
\n

\nz\n=\n\n1.6\n (may be seen in part (d))     A1  N1

\n

Note: Depending on the candidate’s interpretation of the question, they may give \n\n\n1\n\nm\n\ns\n\n as the answer to part (c). Such answers should be awarded the first (M1) in part (d), even when part (d) is left blank. If the candidate goes on to show \nz\n=\n\n1.6\n as part of their working in part (d), the A1 in part (c) may be awarded.

\n

[1 mark]

\n
c.
\n
\n

attempt to standardize \nx\n (do not accept \n\n\nx\n\nμ\n\nσ\n\n)       (M1)

\n

eg   \n\n\n1\n\nm\n\ns\n\n (may be seen in part (c)), \n\n\nm\n\n2\n\ns\n\n,  \n\n\nx\n\nm\n\nσ\n\n

\n

correct equation with each \nz\n-value      (A1)(A1)

\n

eg   \n\n1.6\n=\n\n\n1\n\nm\n\ns\n\n,  \n2.4\n=\n\n\n2\n\nm\n\ns\n\n,  \nm\n+\n2.4\ns\n=\n2\n

\n

valid approach (to set up equation in one variable)       M1

\n

eg   \n2.4\n=\n\n\n2\n\n\n(\n\n1.6\ns\n+\n1\n\n)\n\n\ns\n\n,   \n\n\n1\n\nm\n\n\n\n1.6\n\n\n=\n\n\n2\n\nm\n\n\n2.4\n\n\n

\n

correct working        (A1)

\n

eg   \n1.6\ns\n+\n1\n=\n2\n\n2.4\ns\n,  \n4\ns\n=\n1\n,  \nm\n=\n\n7\n5\n\n

\n

\ns\n=\n\n1\n4\n\n       A1 N2

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "19M.1.SL.TZ1.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

In a class of 30 students, 19 play tennis, 3 play both tennis and volleyball, and 6 do not play either sport.

\n

The following Venn diagram shows the events “plays tennis” and “plays volleyball”. The values t and v represent numbers of students.

\n

\n
\n

Find the value of t.

\n
[2]
\n
a.i.
\n
\n

Find the value of v.

\n
[2]
\n
a.ii.
\n
\n

Find the probability that a randomly selected student from the class plays tennis or volleyball, but not both.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

valid approach to find t       (M1)

\n

eg  t+3=19, 19-3

\n

t=16 (may be seen on Venn diagram)        A1 N2

\n

[2 marks]

\n
a.i.
\n
\n

valid approach to find v       (M1)

\n

eg  t+3+v+6=30, 30-19-6

\n

v=5 (may be seen on Venn diagram)        A1 N2

\n

[2 marks]

\n
a.ii.
\n
\n

valid approach       (M1)

\n

eg  16+521 students, 1-3+630

\n

2130 =710        A1 N2

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
", "question_id": "20N.1.SL.TZ0.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A nationwide study on reaction time is conducted on participants in two age groups. The participants in Group X are less than 40 years old. Their reaction times are normally distributed with mean 0.489 seconds and standard deviation 0.07 seconds.

\n
\n

The participants in Group Y are 40 years or older. Their reaction times are normally distributed with mean 0.592 seconds and standard deviation σ seconds.

\n
\n

In the study, 38 % of the participants are in Group X.

\n
\n

A person is selected at random from Group X. Find the probability that their reaction time is greater than 0.65 seconds.

\n
[2]
\n
a.
\n
\n

The probability that the reaction time of a person in Group Y is greater than 0.65 seconds is 0.396. Find the value of σ.

\n
[4]
\n
b.
\n
\n

A randomly selected participant has a reaction time greater than 0.65 seconds. Find the probability that the participant is in Group X.

\n
[6]
\n
c.
\n
\n

Ten of the participants with reaction times greater than 0.65 are selected at random. Find the probability that at least two of them are in Group X.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

0.010724

\n

0.0107      A2 N2

\n

 

\n

[2 marks]

\n
a.
\n
\n

correct z-value      (A1)

\n

0.263714…

\n

evidence of appropriate approach      (M1)

\n

eg    \n\n\n0.65\n\n0.592\n\nσ\n\n,   \n0.264\n=\n\n\nx\n\nu\n\nσ\n\n

\n

correct substitution      (A1)

\n

eg    \n0.263714\n=\n\n\n0.65\n\n0.592\n\nσ\n\n,   \nσ\n=\n\n\n0.65\n\n0.592\n\n\n0.264\n\n\n

\n

0.219934

\n

σ = 0.220     A1 N3

\n

 

\n

[4 marks]

\n
b.
\n
\n

correct work for P(group X and \nt\n > 0.65) or P(group Y and \nt\n > 0.65)  (may be seen anywhere)     (A1)

\n

eg    \n\nP\n\n\n(\n\n\ngroup X\n\n\n)\n\n×\n\nP\n\n\n(\n\nt\n>\n0.65\n\n|\n\nX\n\n\n\n\n)\n\n,   \n\nP\n\n\n(\n\n\nX\n\n\nt\n>\n0.65\n\n)\n\n=\n0.0107\n×\n0.38\n\n(\n\n=\n0.004075\n\n)\n\n,

\n

\n\nP\n\n\n(\n\n\nY\n\n\nt\n>\n0.65\n\n)\n\n=\n0.396\n×\n0.62\n

\n

recognizing conditional probability (seen anywhere)      (M1)

\n

eg    \n\nP\n\n\n(\n\n\n\n\nX\n\n|\n\nt\n>\n0.65\n\n)\n\n,   \n\nP\n\n\n(\n\n\n\nA\n|\n\nB\n\n)\n\n=\n\n\n\nP\n\n\n(\n\nA\n\nB\n\n)\n\n\n\n\nP\n\n\n(\nB\n)\n\n\n\n

\n

valid approach to find \n\nP\n\n\n(\n\nt\n>\n0.65\n\n)\n\n     (M1)

\n

eg   ,  \n\nP\n\n\n(\n\n\nX and \n\nt\n>\n0.65\n\n)\n\n+\n\nP\n\n\n(\n\n\nY and \n\nt\n>\n0.65\n\n)\n\n

\n

correct work for \n\nP\n\n\n(\n\nt\n>\n0.65\n\n)\n\n     (A1)

\n

eg   0.0107 × 0.38 + 0.396 × 0.62,  0.249595

\n

correct substitution into conditional probability formula      A1

\n

eg   \n\n\n0.0107\n×\n0.38\n\n\n0.0107\n×\n0.38\n+\n0.396\n×\n0.62\n\n\n,  \n\n\n0.004075\n\n\n0.249595\n\n\n

\n

0.016327

\n

\n\nP\n\n\n(\n\n\n\n\nX\n\n|\n\nt\n>\n0.65\n\n)\n\n=\n0.0163270\n     A1 N3

\n

 

\n

[6 marks]

\n
c.
\n
\n

recognizing binomial probability      (M1)

\n

eg    \nX\n\nB\n\n(\n\nn\n,\n\n\np\n\n)\n\n,  \n\n(\n\n\n\n\nn\n\n\n\n\nr\n\n\n\n\n)\n\n\n\np\nr\n\n\n\n\nq\n\nn\n\nr\n\n\n\n,  (0.016327)2(0.983672)8,  \n\n(\n\n\n\n\n\n10\n\n\n\n\n\n2\n\n\n\n\n)\n\n

\n

valid approach      (M1)

\n

eg    \n\nP\n\n\n(\n\nX\n\n2\n\n)\n\n=\n1\n\n\nP\n\n\n(\n\nX\n\n1\n\n)\n\n,   \n1\n\n\nP\n\n\n(\n\nX\n<\na\n\n)\n\n,  summing terms from 2 to 10 (accept binomcdf(10, 0.0163, 2, 10))

\n

0.010994

\n

\n\nP\n\n\n(\n\nX\n\n2\n\n)\n\n=\n0.0110\n     A1 N2

\n

 

\n

[3 marks] 

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "18N.2.SL.TZ0.S_9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Write down the remainder when 142022 is divided by 7.

\n
[1]
\n
a.i.
\n
\n

Use Fermat’s little theorem to find the remainder when 142022 is divided by 17.

\n
[4]
\n
a.ii.
\n
\n

Prove that a number in base 13 is divisible by 6 if, and only if, the sum of its digits is divisible by 6.

\n
[4]
\n
b.i.
\n
\n

The base 13 number 1y93y25 is divisible by 6. Find the possible values of the digit y.

\n
[4]
\n
b.ii.
\n
", "Markscheme": "
\n

the remainder is 0       A1

\n


[1 mark]

\n
a.i.
\n
\n

14161mod17  (from Fermat’s little theorem)        (A1)

\n

142022=1416×126+6        (M1)

\n


Note: Award M1 for a RHS exponent consistent with the correct use of Fermat’s little theorem.

\n


142022146mod17  15mod17       A1

\n

the remainder is 15       A1

\n


[4 marks]

\n
a.ii.
\n
\n

METHOD 1

\n

let N=an13n+an-113n-1++a113+a0       M1

\n


Note: The above M1 is independent of the A marks below.

\n


131mod6       A1

\n


EITHER

\n

13x1mod6  (for all x)       A1

\n


OR

\n

Nan1n+an-11n-1++a11+a0mod6  Nan+an-1++a1+a0mod6       A1

\n


THEN

\n

so N0mod6 if and only if an+an-1++a1+a00mod6       R1

\n

so 6N if and only if 6an+an-1++a1+a0       AG

\n

 

\n

METHOD 2

\n

let N=an13n+an-113n-1++a113+a0       (M1)

\n

N=an+an-1++a1+a0+13-1an13n-1++130+an-113n-2++130++a1130       M1A1

\n


Note: Award M1 for attempting to express N in the form N=an+an-1++a1+a0+13-1M.

\n


as 613-1M       R1

\n

so 6N if and only if 6an+an-1++a1+a0       AG

\n


[4 marks]

\n
b.i.
\n
\n

METHOD 1

\n

the sum of the digits is 2y+20       (A1)

\n

uses 2y+20=6k  (or equivalent) to attempt to find a valid value of y       (M1)

\n

y=2,5,8,11B       A1A1

\n


Note: Award A1 for y=2,5,8 and A1 for y=11(B).

\n

 

\n

METHOD 2

\n

1y93y2513=1×136+y×135+9×134+3×133+y×132+2×131+5×130       (A1)

\n

=371462y+5090480

\n

attempts to find a valid value of y such that

\n

371462y+50904800mod6       (M1)

\n

y=2,5,8,11B       A1A1

\n


Note: Award A1 for y=2,5,8 and A1 for y=11(B).

\n


[4 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "20N.3.AHL.TZ0.HDM_3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-7-laws-of-exponents-and-logs" ] }, { "Question": "
\n

A biased four-sided die is rolled. The following table gives the probability of each score.

\n

\n
\n

Find the value of k.

\n
[2]
\n
a.
\n
\n

Calculate the expected value of the score.

\n
[2]
\n
b.
\n
\n

The die is rolled 80 times. On how many rolls would you expect to obtain a three?

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of summing to 1      (M1)

\n

eg   0.28 + k + 1.5 + 0.3 = 1,  0.73 + k = 1

\n

k = 0.27     A1 N2

\n

[2 marks]

\n
a.
\n
\n

correct substitution into formula for E (X)      (A1)
eg  1 × 0.28 + 2 × k + 3 × 0.15 + 4 × 0.3

\n

E (X) = 2.47  (exact)      A1 N2

\n

[2 marks]

\n
b.
\n
\n

valid approach      (M1)

\n

eg  np, 80 × 0.15

\n

12     A1 N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.2.SL.TZ1.S_2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

The mass M of apples in grams is normally distributed with mean μ. The following table shows probabilities for values of M.

\n

\n
\n

The apples are packed in bags of ten.

\n

Any apples with a mass less than 95 g are classified as small.

\n
\n

Write down the value of k.

\n
[2]
\n
a.i.
\n
\n

Show that μ = 106.

\n
[2]
\n
a.ii.
\n
\n

Find P(M < 95) .

\n
[5]
\n
b.
\n
\n

Find the probability that a bag of apples selected at random contains at most one small apple.

\n
[3]
\n
c.
\n
\n

Find the expected number of bags in this crate that contain at most one small apple.

\n
[3]
\n
d.i.
\n
\n

Find the probability that at least 48 bags in this crate contain at most one small apple.

\n
[2]
\n
d.ii.
\n
", "Markscheme": "
\n

evidence of using \n\n\n\n\np\ni\n\n\n\n=\n1\n     (M1)

\n

eg   k + 0.98 + 0.01 = 1

\n

k = 0.01     A1 N2

\n

[2 marks]

\n
a.i.
\n
\n

recognizing that 93 and 119 are symmetrical about μ       (M1)

\n

eg   μ is midpoint of 93 and 119

\n

correct working to find μ       A1

\n

\n\n\n119\n+\n93\n\n2\n\n

\n

μ = 106     AG N0

\n

[2 marks]

\n
a.ii.
\n
\n

finding standardized value for 93 or 119      (A1)
eg   z = −2.32634, z = 2.32634

\n

correct substitution using their z value      (A1)
eg  \n\n\n93\n\n106\n\nσ\n\n=\n\n2.32634\n,\n\n\n\n\n119\n\n106\n\n\n2.32634\n\n\n=\nσ\n

\n

σ = 5.58815     (A1)

\n

0.024508

\n

P(X < 95) = 0.0245      A2 N3

\n

[5 marks]

\n
b.
\n
\n

evidence of recognizing binomial    (M1) 

\n

eg 10, ananaCpqn−=××and 0.024B(5,,)pnp

\n

valid approach    (M1) 

\n

eg P(1),P(0)P(1)XXX≤=+= 

\n

0.976285 

\n

0.976     A1 N2 

\n

[3 marks]

\n
c.
\n
\n

recognizing new binomial probability      (M1)
eg     B(50, 0.976)

\n

correct substitution      (A1)
eg     E(X) = 50 (0.976285)

\n

48.81425

\n

48.8    A1 N2

\n

[3 marks]

\n
d.i.
\n
\n

valid approach      (M1)

\n

eg   P(X ≥ 48), 1 − P(X ≤ 47)

\n

0.884688

\n

0.885       A1 N2

\n

[2 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "18M.2.SL.TZ2.S_10", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

The function f is defined for all x. The line with equation y=6x-1 is the tangent to the graph of f at x=4.

\n
\n

The function g is defined for all x where gx=x2-3x and hx=fgx.

\n
\n

Write down the value of f(4).

\n
[1]
\n
a.
\n
\n

Find f(4).

\n
[1]
\n
b.
\n
\n

Find h(4).

\n
[2]
\n
c.
\n
\n

Hence find the equation of the tangent to the graph of h at x=4.

\n
[3]
\n
d.
\n
", "Markscheme": "
\n

f'(4)=6               A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

f(4)=6×4-1=23               A1

\n

 

\n

[1 mark]

\n
b.
\n
\n

h4=fg4                 (M1)

\n

h4=f42-3×4=f4

\n

h4=23                 A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

attempt to use chain rule to find h'                 (M1)

\n

f'gx×g'x   OR   x2-3x'×f'x2-3x

\n

h'4=2×4-3f'42-3×4                 A1

\n

         =30 

\n

y-23=30x-4   OR   y=30x-97                 A1

\n

 

\n

[3 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21N.1.SL.TZ0.5", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-1-equations-of-straight-lines-parallel-and-perpendicular" ] }, { "Question": "
\n

A particle P moves along the x-axis. The velocity of P is vms-1 at time t seconds, where v(t)=4+4t-3t2 for 0t3. When t=0, P is at the origin O.

\n
\n

Find the value of t when P reaches its maximum velocity.

\n
[2]
\n
a.i.
\n
\n

Show that the distance of P from O at this time is 8827 metres.

\n
[5]
\n
a.ii.
\n
\n

Sketch a graph of v against t, clearly showing any points of intersection with the axes.

\n
[4]
\n
b.
\n
\n

Find the total distance travelled by P.

\n
[5]
\n
c.
\n
", "Markscheme": "
\n

valid approach to find turning point (v'=0, -b2a, average of roots)                 (M1)

\n

4-6t=0   OR   -42-3   OR   -23+22

\n

t=23 (s)                 A1

\n

  

\n

[2 marks]

\n
a.i.
\n
\n

attempt to integrate v                 (M1)

\n

vdt=4+4t-3t2 dt=4t+2t2-t3+c                 A1A1

\n


Note: Award A1 for 4t+2t2, A1 for -t3.

\n


attempt to substitute their t into their solution for the integral                 (M1)

\n

distance=423+2232-233

\n

=83+89-827 (or equivalent)                           A1

\n

=8827 (m)                   AG

\n

  

\n

[5 marks]

\n
a.ii.
\n
\n

\n

valid approach to solve 4+4t-3t2=0   (may be seen in part (a))                 (M1)

\n

2-t2+3t  OR  -4±16+48-6

\n

correct x- intercept on the graph at t=2                 A1

\n


Note: The following two A marks may only be awarded if the shape is a concave down parabola. These two marks are independent of each other and the (M1).

\n


correct domain from 0 to 3 starting at (0,4)                 A1

\n


Note: The 3 must be clearly indicated.

\n


vertex in approximately correct place for t=23 and v>4                 A1

\n

 

\n

[4 marks]

\n
b.
\n
\n

recognising to integrate between 0 and 2, or 2 and 3   OR   034+4t-3t2dt                (M1)

\n

024+4t-3t2dt

\n

=8                 A1

\n

234+4t-3t2dt

\n

=-5                 A1

\n

valid approach to sum the two areas (seen anywhere)                (M1)

\n

02vdt-23vdt   OR   02vdt+23vdt

\n

total distance travelled =13 (m)                 A1

\n

 

\n

[5 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21N.1.SL.TZ0.7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

A jar contains 5 red discs, 10 blue discs and \nm\n green discs. A disc is selected at random and replaced. This process is performed four times.

\n
\n

Write down the probability that the first disc selected is red.

\n
[1]
\n
a.
\n
\n

Let \nX\n be the number of red discs selected. Find the smallest value of \nm\n for which \n\nVar\n\n(\nX\n\n \n\n)\n<\n0.6\n.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nP(red)\n\n=\n\n5\n\n15\n+\nm\n\n\n     A1     N1

\n

[1 mark]

\n
a.
\n
\n

recognizing binomial distribution     (M1)

\n

eg\n\n\n\n\n\n\nX\n\nB\n(\nn\n,\n\n \n\np\n)\n

\n

correct value for the complement of their \np\n (seen anywhere)     A1

\n

eg\n\n\n\n\n\n\n1\n\n\n5\n\n15\n+\nm\n\n\n,\n\n \n\n\n\n10\n+\nm\n\n\n15\n+\nm\n\n\n

\n

correct substitution into \n\nVar\n\n(\nX\n)\n=\nn\np\n(\n1\n\np\n)\n     (A1)

\n

eg\n\n\n\n\n\n\n4\n\n(\n\n\n5\n\n15\n+\nm\n\n\n\n)\n\n\n(\n\n\n\n10\n+\nm\n\n\n15\n+\nm\n\n\n\n)\n\n,\n\n \n\n\n\n20\n(\n10\n+\nm\n)\n\n\n\n\n\n(\n15\n+\nm\n)\n\n2\n\n\n\n\n<\n0.6\n

\n

\nm\n>\n12.2075\n     (A1)

\n

\nm\n=\n13\n     A1     N3

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "16N.2.SL.TZ0.S_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

Consider the function fx=ax where x, a and x>0, a>1.

\n

The graph of f contains the point 23,4.

\n
\n

Consider the arithmetic sequence log827 , log8p , log8q , log8125 , where p>1 and q>1.

\n
\n

Show that a=8.

\n
[2]
\n
a.
\n
\n

Write down an expression for f-1x.

\n
[1]
\n
b.
\n
\n

Find the value of f-132.

\n
[3]
\n
c.
\n
\n

Show that 27, p, q and 125 are four consecutive terms in a geometric sequence.

\n
[4]
\n
d.i.
\n
\n

Find the value of p and the value of q.

\n
[5]
\n
d.ii.
\n
", "Markscheme": "
\n

f23=4   OR   a23=4             (M1)

\n

a=432   OR   a=2232   OR   a2=64   OR   a3=2                 A1

\n

a=8                 AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

f-1x=log8x                 A1

\n


Note:
Accept f-1x=logax.
         Accept any equivalent expression for f-1 e.g. f-1x=lnxln8.

\n

 

\n

[1 mark]

\n
b.
\n
\n

correct substitution                 (A1)

\n

log832   OR   8x=3212

\n

correct working involving log/index law                 (A1)

\n

12log832   OR   52log82   OR   log82=13   OR   log2252   OR   log28=3   OR   ln252ln23   OR   23x=252

\n

f-132=56                 A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

METHOD 1

\n

equating a pair of differences               (M1)

\n

u2-u1=u4-u3=u3-u2

\n

log8p-log827=log8125-log8q

\n

log8125-log8q=log8q-log8p

\n

log8p27=log8125q, log8125q=log8qp           A1A1

\n

p27=125q  and  125q=qp           A1

\n

27, p, q and 125 are in geometric sequence           AG

\n


Note:
If candidate assumes the sequence is geometric, award no marks for part (i). If r=53 has been found, this will be awarded marks in part (ii).

\n

 

\n

METHOD 2

\n

expressing a pair of consecutive terms, in terms of d               (M1)

\n

p=8d×27 and q=82d×27   OR   q=82d×27 and 125=83d×27

\n

two correct pairs of consecutive terms, in terms of d                 A1

\n

8d×2727=82d×278d×27=83d×2782d×27  (must include 3 ratios)                 A1

\n

all simplify to 8d                 A1

\n

27, p, q and 125 are in geometric sequence           AG

\n

 

\n

[4 marks]

\n
d.i.
\n
\n

METHOD 1 (geometric, finding r)

\n

u4=u1r3   OR   125=27r3                 (M1)

\n

r=53  (seen anywhere)                 A1

\n

p=27r   OR   125q=53                 (M1)

\n

p=45, q=75       A1A1

\n

 

\n

METHOD 2 (arithmetic)

\n

u4=u1+3d   OR   log8125=log827+3d                 (M1)

\n

d=log853  (seen anywhere)                 A1

\n

log8p=log827+log853   OR   log8q=log827+2log853                 (M1)

\n

p=45, q=75       A1A1

\n

 

\n

METHOD 3 (geometric using proportion)

\n

recognizing proportion                 (M1)

\n

pq=125×27   OR   q2=125p   OR   p2=27q

\n

two correct proportion equations                 A1

\n

attempt to eliminate either p or q                 (M1)

\n

q2=125×125×27q   OR   p2=27×125×27p

\n

p=45, q=75       A1A1

\n

 

\n

[5 marks]

\n
d.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
", "question_id": "21N.1.SL.TZ0.8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

In a large university the probability that a student is left handed is 0.08. A sample of 150 students is randomly selected from the university. Let \nk\n be the expected number of left-handed students in this sample.

\n
\n

Find k .

\n
[2]
\n
a.
\n
\n

Hence, find the probability that exactly k students are left handed;

\n
[2]
\n
b.i.
\n
\n

Hence, find the probability that fewer than k students are left handed.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

evidence of binomial distribution (may be seen in part (b))     (M1)

\n

eg n p ,   150 × 0.08

\n

k = 12     A1     N2

\n

[2 marks]

\n
a.
\n
\n

P ( X = 12 ) = ( 150 12 ) ( 0.08 ) 12 ( 0.92 ) 138     (A1)

\n

0.119231

\n

probability = 0.119     A1     N2

\n

[2 marks]

\n
b.i.
\n
\n

recognition that X 11     (M1)

\n

0.456800

\n

P ( X < 12 ) = 0.457     A1     N2

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "17M.2.SL.TZ1.S_4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-8-binomial-distribution" ] }, { "Question": "
\n

The following table shows the probability distribution of a discrete random variable \nX\n.

\n

\n
\n

Find the value of \nk\n.

\n
[3]
\n
a.
\n
\n

Find \n\nE\n\n\n(\nX\n)\n\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of using \n\n\np\n=\n1\n\n      (M1)

\n

correct working      (A1)

\n

eg   \n\n3\n\n13\n\n\n+\n\n1\n\n13\n\n\n+\n\n4\n\n13\n\n\n+\nk\n=\n1\n,  \n1\n\n\n8\n\n13\n\n\n

\n

\nk\n=\n\n5\n\n13\n\n\n      A1 N2

\n

[3 marks]

\n

 

\n
a.
\n
\n

valid approach to find \n\nE\n\n\n(\nX\n)\n\n     (M1)

\n

eg   \n1\n×\n\n1\n\n13\n\n\n+\n2\n×\n\n4\n\n13\n\n\n+\n3\n×\nk\n,  \n0\n×\n\n3\n\n13\n\n\n+\n1\n×\n\n1\n\n13\n\n\n+\n2\n×\n\n4\n\n13\n\n\n+\n3\n×\n\n5\n\n13\n\n\n

\n

correct working      (A1)

\n

eg   \n\n1\n\n13\n\n\n+\n\n8\n\n13\n\n\n+\n\n\n15\n\n\n13\n\n\n

\n

\n\nE\n\n\n(\nX\n)\n\n=\n\n\n24\n\n\n13\n\n\n      A1  N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "19M.1.SL.TZ2.S_1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-7-discrete-random-variables" ] }, { "Question": "
\n

The heights of adult males in a country are normally distributed with a mean of 180 cm and a standard deviation of \nσ\n\n cm\n\n. 17% of these men are shorter than 168 cm. 80% of them have heights between \n(\n192\n\nh\n)\n\n cm\n\n and 192 cm.

\n

Find the value of \nh\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

finding the \nz\n-value for 0.17     (A1)

\n

eg\n\n\n\n\n\n\nz\n=\n\n0.95416\n

\n

setting up equation to find \nσ\n,     (M1)

\n

eg\n\n\n\n\n\n\nz\n=\n\n\n168\n\n180\n\nσ\n\n,\n\n \n\n\n0.954\n=\n\n\n\n12\n\nσ\n\n

\n

\nσ\n=\n12.5765\n     (A1)

\n

EITHER (Properties of the Normal curve)

\n

correct value (seen anywhere)     (A1)

\n

eg\n\n\n\n\n\n\n\nP\n\n(\nX\n<\n192\n)\n=\n0.83\n,\n\n P\n\n(\nX\n>\n192\n)\n=\n0.17\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n\nP\n\n(\nX\n<\n192\n\nh\n)\n=\n0.83\n\n0.8\n,\n\n P\n\n(\nX\n<\n192\n\nh\n)\n=\n1\n\n0.8\n\n0.17\n,\n

\n

\n\nP\n\n(\nX\n>\n192\n\nh\n)\n=\n0.8\n+\n0.17\n

\n

correct equation in \nh\n

\n

eg\n\n\n\n\n\n\n\n\n(\n192\n\nh\n)\n\n180\n\n\n12.576\n\n\n=\n\n1.88079\n,\n\n \n\n192\n\nh\n=\n156.346\n     (A1)

\n

35.6536

\n

\nh\n=\n35.7\n     A1     N3

\n

OR (Trial and error using different values of h)

\n

two correct probabilities whose 2 sf will round up and down, respectively, to 0.8     A2

\n

eg\n\n\n\n\n\n\n\nP\n\n(\n192\n\n35.6\n<\nX\n<\n192\n)\n=\n0.799706\n,\n\n P\n\n(\n157\n<\nX\n<\n192\n)\n=\n0.796284\n,\n

\n

\n\nP\n\n(\n192\n\n36\n<\nX\n<\n192\n)\n=\n0.801824\n

\n

\nh\n=\n35.7\n     A2

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.2.SL.TZ0.S_7", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

The weights, \nW\n, of newborn babies in Australia are normally distributed with a mean 3.41 kg and standard deviation 0.57 kg. A newborn baby has a low birth weight if it weighs less than \nw\n kg.

\n
\n

Given that 5.3% of newborn babies have a low birth weight, find \nw\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)

\n

eg\n\n\n\n\n\n\nz\n=\n\n1.61643\n\"N16/5/MATME/SP2/ENG/TZ0/05.a/M\"

\n

2.48863

\n

\nw\n=\n2.49\n\n (kg)\n\n     A2     N3

\n

[3 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.2.SL.TZ0.S_5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Show that 2x-3-6x-1=2x2-5x-3x-1, x, x1.

\n
[2]
\n
a.
\n
\n

Hence or otherwise, solve the equation  2sin2θ-3-6sin2θ-1=0  for  0θπ, θπ4.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

attempt to write all LHS terms with a common denominator of x-1                 (M1)

\n

2x-3-6x-1=2xx-1-3x-1-6x-1   OR   2x-3x-1x-1-6x-1

\n

=2x2-2x-3x+3-6x-1   OR   2x2-5x+3x-1-6x-1                 A1

\n

=2x2-5x-3x-1                 AG

\n

 

\n

METHOD 2

\n

attempt to use algebraic division on RHS                 (M1)

\n

correctly obtains quotient of 2x-3 and remainder -6                 A1

\n

=2x-3-6x-1 as required.                 AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

consider the equation 2sin22θ-5sin2θ-3sin2θ-1=0                 (M1)

\n

2sin22θ-5sin2θ-3=0

\n


EITHER

\n

attempt to factorise in the form 2sin2θ+asin2θ+b                 (M1)

\n


Note:
Accept any variable in place of sin2θ.

\n


2sin2θ+1sin2θ-3=0

\n


OR

\n

attempt to substitute into quadratic formula                 (M1)

\n

sin2θ=5±494

\n


THEN

\n

sin2θ=-12  or  sin2θ=3                 (A1)

\n


Note:
Award A1 for sin2θ=-12 only.

\n


one of 7π6  OR  11π6   (accept 210 or 330)                 (A1)

\n

θ=7π12,11π12  (must be in radians)                 A1

\n


Note:
Award A0 if additional answers given.

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.1.SL.TZ0.6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-6-simple-proof" ] }, { "Question": "
\n

Consider f(x), g(x) and h(x), for x∈ R where h(x) =  ( f g ) (x).

\n

Given that g(3) = 7 , g′ (3) = 4 and f ′ (7) = −5 , find the gradient of the normal to the curve of h at x = 3.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

recognizing the need to find h′      (M1)

\n

recognizing the need to find h′ (3) (seen anywhere)      (M1)

\n

evidence of choosing chain rule        (M1)

\n

eg    d y d x = d y d u × d u d x , f ( g ( 3 ) ) × g ( 3 ) , f ( g ) × g

\n

correct working       (A1)

\n

eg   f ( 7 ) × 4 , 5 × 4

\n

h ( 3 ) = 20       (A1)

\n

evidence of taking their negative reciprocal for normal       (M1)

\n

eg   1 h ( 3 ) , m 1 m 2 = 1

\n

gradient of normal is  1 20       A1 N4

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18M.1.SL.TZ1.S_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

The random variable \nX\n is normally distributed with a mean of 100. The following diagram shows the normal curve for \nX\n.

\n

\"M17/5/MATME/SP1/ENG/TZ2/03\"

\n

Let \nR\n be the shaded region under the curve, to the right of 107. The area of \nR\n is 0.24.

\n
\n

Write down \n\nP\n\n(\nX\n>\n107\n)\n.

\n
[1]
\n
a.
\n
\n

Find \n\nP\n\n(\n100\n<\nX\n<\n107\n)\n.

\n
[3]
\n
b.
\n
\n

Find \n\nP\n\n(\n93\n<\nX\n<\n107\n)\n.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n\nP\n\n(\nX\n>\n107\n)\n=\n0.24\n\n\n\n\n(\n\n=\n\n6\n\n25\n\n\n,\n\n \n\n24\n%\n\n)\n\n     A1     N1

\n

[1 mark]

\n
a.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\nP\n\n(\nX\n>\n100\n)\n=\n0.5\n,\n\n P\n\n(\nX\n>\n100\n)\n\n\nP\n\n(\nX\n>\n107\n)\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n0.5\n\n0.24\n,\n\n \n\n0.76\n\n0.5\n

\n

\n\nP\n\n(\n100\n<\nX\n<\n107\n)\n=\n0.26\n\n\n\n\n(\n\n=\n\n\n13\n\n\n50\n\n\n,\n\n \n\n26\n%\n\n)\n\n     A1     N2

\n

[3 marks]

\n
b.
\n
\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n2\n×\n0.26\n,\n\n \n\n1\n\n2\n(\n0.24\n)\n,\n\n P\n\n(\n93\n<\nX\n<\n100\n)\n=\n\nP\n\n(\n100\n<\nX\n<\n107\n)\n

\n

\n\nP\n\n(\n93\n<\nX\n<\n107\n)\n=\n0.52\n\n\n\n\n(\n\n=\n\n\n13\n\n\n25\n\n\n,\n\n \n\n52\n%\n\n)\n\n     A1 N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ2.S_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\nx\n3\n\n\n\n2\n\n\nx\n2\n\n\n+\na\nx\n+\n6\n. Part of the graph of \nf\n is shown in the following diagram.

\n

\n

The graph of \nf\n crosses the \ny\n-axis at the point P. The line L is tangent to the graph of \nf\n at P.

\n
\n

Find f ( x ) .

\n
[2]
\n
b.i.
\n
\n

Hence, find the equation of L in terms of a .

\n
[4]
\n
b.ii.
\n
\n

The graph of f has a local minimum at the point Q. The line L passes through Q.

\n

Find the value of a .

\n
[8]
\n
c.
\n
", "Markscheme": "
\n

f = 3 x 2 4 x + a      A2 N2

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

valid approach      (M1)

\n

eg    f ( 0 )

\n

correct working      (A1)

\n

eg    3 ( 0 ) 2 4 ( 0 ) + a ,  slope =  a ,   f ( 0 ) = a

\n

attempt to substitute gradient and coordinates into linear equation      (M1)

\n

eg    y 6 = a ( x 0 ) ,   y 0 = a ( x 6 ) ,   6 = a ( 0 ) + c L  = a x + 6

\n

correct equation      A1 N3

\n

eg   y = a x + 6 ,   y 6 = a x ,   y 6 = a ( x 0 )

\n

 

\n

[4 marks]

\n
b.ii.
\n
\n

valid approach to find intersection      (M1)

\n

eg    f ( x ) = L

\n

correct equation      (A1)

\n

eg    x 3 2 x 2 + a x + 6 = a x + 6

\n

correct working      (A1)

\n

eg    x 3 2 x 2 = 0 ,   x 2 ( x 2 ) = 0

\n

x = 2 at Q      (A1)

\n

 

\n

valid approach to find minimum      (M1)

\n

eg    f ( x ) = 0

\n

correct equation      (A1)

\n

eg    3 x 2 4 x + a = 0

\n

substitution of their value of x at Q into their f ( x ) = 0 equation      (M1)

\n

eg    3 ( 2 ) 2 4 ( 2 ) + a = 0 ,   12 8 + a = 0

\n

a = −4     A1 N0

\n

 

\n

[8 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.1.SL.TZ0.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Consider the function \nf\n\n(\nx\n)\n\n=\n\n\nx\n2\n\n\n\n\n\ne\n\n\n3\nx\n\n\n\n,  \nx\n\n\nR\n\n.

\n
\n

The graph of f has a horizontal tangent line at x = 0 and at x = a . Find a .

\n
", "Markscheme": "
\n

valid method    (M1)

\n

eg    f ( x ) = 0

\n

a = 0.667 ( = 2 3 )   (accept  x = 0.667 )     A1 N2

\n

[2 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.2.SL.TZ1.S_3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

A closed cylindrical can with radius r centimetres and height h centimetres has a volume of 20\nπ\n cm3.

\n

\n
\n

The material for the base and top of the can costs 10 cents per cm2 and the material for the curved side costs 8 cents per cm2. The total cost of the material, in cents, is C.

\n
\n

Express h in terms of r.

\n
[2]
\n
a.
\n
\n

Show that \nC\n=\n20\nπ\n\n\nr\n2\n\n\n+\n\n\n320\nπ\n\nr\n\n.

\n
[4]
\n
b.
\n
\n

Given that there is a minimum value for C, find this minimum value in terms of \nπ\n.

\n
[9]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

correct equation for volume      (A1)
eg  \nπ\n\n\nr\n2\n\n\nh\n=\n20\nπ\n

\n

\nh\n=\n\n\n20\n\n\n\n\nr\n2\n\n\n\n\n     A1 N2

\n

[2 marks]

\n

 

\n
a.
\n
\n

attempt to find formula for cost of parts      (M1)
eg  10 × two circles, 8 × curved side

\n

correct expression for cost of two circles in terms of r (seen anywhere)      A1
eg  \n2\nπ\n\n\nr\n2\n\n\n×\n10\n

\n

correct expression for cost of curved side (seen anywhere)      (A1)
eg  \n2\nπ\nr\n×\nh\n×\n8\n

\n

correct expression for cost of curved side in terms of     A1
eg  \n8\n×\n2\nπ\nr\n×\n\n\n20\n\n\n\n\nr\n2\n\n\n\n\n,\n\n\n\n\n320\nπ\n\n\n\n\nr\n2\n\n\n\n\n

\n

\nC\n=\n20\nπ\n\n\nr\n2\n\n\n+\n\n\n320\nπ\n\nr\n\n      AG N0

\n

[4 marks]

\n
b.
\n
\n

recognize \n\nC\n\n\n=\n0\n at minimum       (R1)
eg  \n\nC\n\n\n=\n0\n,\n\n\n\n\n\nd\n\nC\n\n\n\nd\n\nr\n\n\n=\n0\n

\n

correct differentiation (may be seen in equation)

\n

\n\nC\n\n\n=\n40\nπ\nr\n\n\n\n320\nπ\n\n\n\n\nr\n2\n\n\n\n\n        A1A1

\n

correct equation      A1
eg  \n40\nπ\nr\n\n\n\n320\nπ\n\n\n\n\nr\n2\n\n\n\n\n=\n0\n,\n\n\n40\nπ\nr\n\n\n320\nπ\n\n\n\n\nr\n2\n\n\n\n\n

\n

correct working     (A1)
eg  \n40\n\n\nr\n3\n\n\n=\n320\n,\n\n\n\n\nr\n3\n\n\n=\n8\n

\n

r = 2 (m)     A1

\n

attempt to substitute their value of r into C
eg  \n20\nπ\n×\n4\n+\n320\n×\n\nπ\n2\n\n     (M1)

\n

correct working
eg  \n80\nπ\n+\n160\nπ\n        (A1)

\n

\n240\nπ\n (cents)      A1 N3

\n

Note: Do not accept 753.6, 753.98 or 754, even if 240\nπ\n is seen.

\n

[9 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18M.1.SL.TZ2.S_9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Consider a function f with domain a<x<b. The following diagram shows the graph of f', the derivative of f.

\n

\n

The graph of f', the derivative of f, has x-intercepts at x=p, x=0 and x=t . There are local maximum points at x=q and x=t and a local minimum point at x=r.

\n
\n

Find all the values of x where the graph of f is increasing. Justify your answer.

\n
[2]
\n
a.
\n
\n

Find the value of x where the graph of f has a local maximum.

\n
[1]
\n
b.
\n
\n

Find the value of x where the graph of f has a local minimum. Justify your answer.

\n
[2]
\n
c.i.
\n
\n

Find the values of x where the graph of f has points of inflexion. Justify your answer.

\n
[3]
\n
c.ii.
\n
\n

The total area of the region enclosed by the graph of f', the derivative of f, and the x-axis is 20.

\n

Given that fp+ft=4, find the value of f0.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

Special note: In this question if candidates use the word 'gradient' in their reasoning. e.g. gradient is positive, it must be clear whether this is the gradient of f or the gradient of f' to earn the R mark.

\n

 

\n

f increases when p<x<0                A1

\n

f increases when f'x>0   OR   f' is above the x-axis                R1

\n


Note: Do not award A0R1.

\n

 

\n

[2 marks]

\n
a.
\n
\n

Special note: In this question if candidates use the word 'gradient' in their reasoning. e.g. gradient is positive, it must be clear whether this is the gradient of f or the gradient of f' to earn the R mark.

\n

 

\n

x=0               A1

\n

 

\n

[1 mark]

\n
b.
\n
\n

Special note: In this question if candidates use the word 'gradient' in their reasoning. e.g. gradient is positive, it must be clear whether this is the gradient of f or the gradient of f' to earn the R mark.

\n

 

\n

f is minimum when x=p               A1

\n

because f'p=0, f'x<0 when x<p and f'x>0 when x>p

\n

(may be seen in a sign diagram clearly labelled as f')

\n

OR because f' changes from negative to positive at x=p

\n

OR f'p=0 and slope of f' is positive at x=p               R1

\n

 

\n

Note: Do not award A0 R1

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

Special note: In this question if candidates use the word 'gradient' in their reasoning. e.g. gradient is positive, it must be clear whether this is the gradient of f or the gradient of f' to earn the R mark.

\n

 

\n

f has points of inflexion when x=q, x=r and x=t               A2

\n


f' has turning points at x=q, x=r and x=t

\n

OR

\n

f''q=0, f''r=0 and f''t=0 and f' changes from increasing to decreasing or vice versa at each of these x-values (may be seen in a sign diagram clearly labelled as f'' and f')              R1

\n

 

\n

Note: Award A0 if any incorrect answers are given. Do not award A0R1

\n

 

\n

[3 marks]

\n
c.ii.
\n
\n

Special note: In this question if candidates use the word 'gradient' in their reasoning. e.g. gradient is positive, it must be clear whether this is the gradient of f or the gradient of f' to earn the R mark.

\n

 

\n

recognizing area from p to t (seen anywhere)               M1

\n

ptf'xdx

\n

recognizing to negate integral for area below x-axis               (M1)

\n

p0f'xdx-0tf'xdx   OR   p0f'xdx+t0f'xdx

\n

mnf'xdx=fn-fm (for any integral)               (M1)

\n

f0-fp-ft-f0   OR   f0-fp+f0-ft               (A1)

\n

2f0-ft+fp=20,  2f0-4=20               (A1)

\n

f0=12               A1

\n

 

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "21N.1.SL.TZ0.9", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-2-increasing-and-decreasing-functions" ] }, { "Question": "
\n

The function f is defined by fx=2x+43-x, where x, x3.

\n
\n

Write down the equation of

\n
\n

Find the coordinates where the graph of f crosses

\n
\n

the vertical asymptote of the graph of f.

\n
[1]
\n
a.i.
\n
\n

the horizontal asymptote of the graph of f.

\n
[1]
\n
a.ii.
\n
\n

the x-axis.

\n
[1]
\n
b.i.
\n
\n

the y-axis.

\n
[1]
\n
b.ii.
\n
\n

Sketch the graph of f on the axes below.

\n

\n
[1]
\n
c.
\n
\n

The function g is defined by gx=ax+43-x, where x, x3 and a.

\n

Given that gx=g-1x, determine the value of a.

\n
[4]
\n
d.
\n
", "Markscheme": "
\n

x=3                 A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

y=-2                 A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

-2,0   (accept x=-2)                 A1

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

0,43   (accept y=43 and f0=43)                 A1

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

               A1

\n


Note:
Award A1 for completely correct shape: two branches in correct quadrants with asymptotic behaviour.

\n

 

\n

[1 mark]

\n
c.
\n
\n

METHOD 1

\n

gx=y=ax+43-x

\n

attempt to find x in terms of y                (M1)

\n

OR exchange x and y and attempt to find y in terms of x

\n

3y-xy=ax+4                A1

\n

ax+xy=3y-4

\n

xa+y=3y-4

\n

x=3y-4y+a

\n

g-1x=3x-4x+a                A1

\n


Note: Condone use of y=

\n


gxg-1x

\n

ax+43-x3x-4x+a

\n

a=-3                A1

\n

 

\n

METHOD 2

\n

gx=ax+43-x

\n

attempt to find an expression for ggx and equate to x                (M1)

\n

ggx=aax+43-x+43-ax+43-x=x                A1

\n

aax+4+43-x9-3x-ax+4=x

\n

aax+4+43-x5-3+ax=x

\n

aax+4+43-x=x5-3+ax                A1

\n

equating coefficients of x2  (or similar)

\n

a=-3                A1

\n

 

\n

[4 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "21N.1.AHL.TZ0.2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

The equation 3px2+2px+1=p has two real, distinct roots.

\n
\n

Find the possible values for p.

\n
[5]
\n
a.
\n
\n

Consider the case when p=4. The roots of the equation can be expressed in the form x=a±136, where a. Find the value of a.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

attempt to use discriminant b2-4ac>0                M1

\n

2p2-43p1-p>0

\n

16p2-12p>0                (A1)

\n

p4p-3>0

\n

attempt to find critical values p=0, p=34                M1

\n

recognition that discriminant >0                (M1)

\n

p<0 or p>34                 A1

\n


Note:
Condone ‘or’ replaced with ‘and’, a comma, or no separator

\n

 

\n

[5 marks]

\n
a.
\n
\n

p=412x2+8x-3=0

\n

valid attempt to use x=-b±b2-4ac2a (or equivalent)                M1

\n

x=-8±20824

\n

x=-2±136

\n

a=-2                 A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.1.AHL.TZ0.7", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

Prove by mathematical induction that dndxnx2ex=x2+2nx+nn-1ex for n+.

\n
[7]
\n
a.
\n
\n

Hence or otherwise, determine the Maclaurin series of fx=x2ex in ascending powers of x, up to and including the term in x4.

\n
[3]
\n
b.
\n
\n

Hence or otherwise, determine the value of limx0x2ex-x23x9.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

For n=1

\n

LHS: ddxx2ex=x2ex+2xex=exx2+2x              A1

\n

RHS: x2+21x+11-1ex=exx2+2x              A1

\n

so true for n=1

\n

now assume true for n=k; i.e. dkdxkx2ex=x2+2kx+kk-1ex                             M1

\n


Note:
Do not award M1 for statements such as \"let n=k\". Subsequent marks can still be awarded.

\n


attempt to differentiate the RHS                             M1

\n

dk+1dxk+1x2ex=ddxx2+2kx+kk-1ex

\n

=2x+2kex+x2+2kx+kk-1ex              A1

\n

=x2+2k+1x+kk+1ex              A1

\n

so true for n=k implies true for n=k+1

\n

therefore n=1 true and n=k true n=k+1 true

\n

therefore, true for all n+                    R1

\n


Note:
Award R1 only if three of the previous four marks have been awarded

\n

 

\n

[7 marks]

\n
a.
\n
\n

METHOD 1

\n

attempt to use dndxnx2ex=x2+2nx+nn-1ex             (M1)

\n


Note: For x=0dndxnx2exx=0=nn-1 may be seen.

\n


f0=0,  f'0=0,  f''0=2,  f'''0=6,  f40=12

\n

use of fx=f0+xf'0+x22!f''0+x33!f'''0+x44!f40+              (M1)

\n

fxx2+x3+12x4              A1

\n

 

\n

METHOD 2

\n

'x2× Maclaurin series of ex'             (M1)

\n

x21+x+x22!+             (A1)

\n

fxx2+x3+12x4              A1

\n

 

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

attempt to substitute x2exx2+x3+12x4 into x2ex-x23x9              M1

\n

x2ex-x23x9x2+x3+12x4+-x23x9             (A1)

\n


EITHER

\n

=x3+12x4+3x9                   A1

\n

=x9+higher order termsx9

\n


OR

\n

x3+12x4+x33                   A1

\n

1+12x+3

\n


THEN

\n

=1 + higher order terms

\n

so limx0x2ex-x23x9=1                   A1

\n

 

\n

METHOD 2

\n

limx0x2ex-x23x9=limx0x2ex-x2x33                  M1

\n

=limx0ex-1x3                  (A1)

\n

attempt to use L'Hôpital's rule                  M1

\n

=limx0ex-013

\n

=limx0ex3

\n

=1                  A1

\n

 

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21N.1.AHL.TZ0.11", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

Consider the equation z-13=i, z. The roots of this equation are ω1ω2 and ω3, where Imω2>0 and Imω3<0.

\n
\n

The roots ω1, ω2 and ω3 are represented by the points A, B and C respectively on an Argand diagram.

\n
\n

Consider the equation z-13=iz3, z.

\n
\n

Verify that ω1=1+eiπ6 is a root of this equation.

\n
[2]
\n
a.i.
\n
\n

Find ω2 and ω3, expressing these in the form a+eiθ, where a and θ>0.

\n
[4]
\n
a.ii.
\n
\n

Plot the points A, B and C on an Argand diagram.

\n
[4]
\n
b.
\n
\n

Find AC.

\n
[3]
\n
c.
\n
\n

By using de Moivre’s theorem, show that α=11-eiπ6 is a root of this equation.

\n
[3]
\n
d.
\n
\n

Determine the value of Reα.

\n
[6]
\n
e.
\n
", "Markscheme": "
\n

1+eiπ6-13

\n

=eiπ63                   A1

\n

=eiπ2                  A1

\n

=cosπ2+isinπ2

\n

=i                  AG

\n

 

\n

Note: Candidates who solve the equation correctly can be awarded the above two marks. The working for part (i) may be seen in part (ii).

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

z-13=eiπ2+2πk                  (M1)

\n

z-1=eiπ6+4πk6                  (M1)

\n

k=1ω2=1+ei5π6                  A1

\n

k=2ω3=1+ei9π6                  A1

\n

 

\n

[4 marks]

\n
a.ii.
\n
\n

EITHER

\n

attempt to express eiπ6ei5π6ei9π6 in Cartesian form and translate 1 unit in the positive direction of the real axis                  (M1)

\n


OR

\n

attempt to express w1w2 and w3 in Cartesian form                  (M1)

\n


THEN

\n

\n

Note: To award A marks, it is not necessary to see AB or C, the w1, or the solid lines

\n

                  A1A1A1

\n

 

\n

[4 marks]

\n
b.
\n
\n

valid attempt to find ω1-ω3 or ω3-ω1                     M1

\n

ω1-ω3=1+32+12i-1-i=32+32i  OR  cosπ6+isinπ6+isinπ2

\n

valid attempt to find 32+32i                     M1

\n

=34+94

\n

AC=3                     A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

METHOD 1

\n

z-13=iz3z-1z3=i                     M1

\n

z-1z3=eiπ2                     A1

\n

α-1α=eiπ6                     A1

\n


Note:
This step to change from z to α may occur at any point in MS.

\n


α-1=αeiπ6

\n

α-αeiπ6=1

\n

α1-eiπ6=1

\n

α=11-eiπ6                     AG

\n

 

\n

METHOD 2

\n

z-13=iz3z-1z3=i                     M1

\n

1-1z3=eiπ2                     A1

\n

1-1z=eiπ6                     A1

\n


Note:
 This step to change from z to α may occur at any point in MS.

\n


1-eiπ6=1α

\n

α=11-eiπ6                     AG

\n

 

\n

METHOD 3

\n

LHS=z-13=11-eiπ6-13

\n

=eiπ61-eiπ63

\n

=i1-eiπ63 =i52-332+i332-52                      M1A1

\n


Note: Award M1 for applying de Moivre’s theorem (may be seen in modulus- argument form.)

\n


RHS=iz3=i11-eiπ63

\n

=i1-eiπ63                     A1

\n

 z-13=iz3                     AG

\n

 

\n

METHOD 4

\n

z-13=iz3

\n

z3-3z2+3z-1=iz3

\n

1-iz3-3z2+3z-1=0                     (M1)

\n

1-i11-eiπ63-311-eiπ62+311-eiπ6-1

\n

=1-i-31-eiπ6+31-eiπ62-1-eiπ63                     (A1)

\n

=1-i-31-eiπ6+31-2eiπ6+eiπ3-1-3eiπ6+3eiπ3-eiπ2                     A1

\n

=0                     AG

\n


Note: If the candidate does not interpret their conclusion, award (M1)(A1)A0 as appropriate.

\n

 

\n

[3 marks]

\n
d.
\n
\n

METHOD 1

\n

11-eiπ6=11-cosπ6+isinπ6                    M1

\n

=22-3-i                     A1

\n

attempt to use conjugate to rationalise                    M1

\n

=4-23+2i2-32+1                     A1

\n

=4-23+2i8-43                     A1

\n

=12+14-23i

\n

Reα=12                     A1

\n


Note: Their final imaginary part does not have to be correct in order for the final three A marks to be awarded

\n

 

\n

METHOD 2

\n

11-eiπ6=11-cosπ6+isinπ6                    M1

\n

attempt to use conjugate to rationalise                    M1

\n

=11-cosπ6-isinπ6×1-cosπ6+isinπ61-cosπ6+isinπ6                     A1

\n

=1-cosπ6+isinπ61-cosπ62+sin2π6                     A1

\n

=1-cosπ6+isinπ61-2cosπ6+cos2π6+sin2π6

\n

=1-cosπ6+isinπ62-2cosπ6                     A1

\n

=12+isinπ62-2cosπ6

\n

Reα=12                     A1

\n


Note: Their final imaginary part does not have to be correct in order for the final three A marks to be awarded

\n

 

\n

METHOD 3

\n

attempt to multiply through by -e-iπ12e-iπ12                    M1

\n

11-eiπ6=-e-iπ12eiπ12-e-iπ12                     A1

\n

attempting to re-write in r-cis form                    M1

\n

=-cos-π12+isin-π12cosπ12+isinπ12-cos-π12+isin-π12                     A1

\n

=-cosπ12-isinπ122isinπ12                     A1

\n

=12-12icotπ12 =12+12icotπ12

\n

Reα=12                     A1

\n

 

\n

METHOD 4

\n

attempt to multiply through by 1-e-iπ61-e-iπ6                    M1

\n

11-eiπ6=1-e-iπ61-e-iπ6-eiπ6+1                     A1

\n

attempting to re-write in r-cis form                    M1

\n

=1-cosπ6-isinπ62-2cosπ6                    A1

\n

attempt to re-write in Cartesian form                    M1

\n

=1-32-12i2-3 =2-322-3+i122-3

\n

Reα=12                     A1

\n


Note: Their final imaginary part does not have to be correct in order for the final A mark to be awarded

\n

 

\n

[6 marks]

\n
e.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "21N.1.AHL.TZ0.12", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag" ] }, { "Question": "
\n

Solve the differential equation dydx=ln2xx2-2yx, x>0, given that y=4 at x=12.

\n

Give your answer in the form y=fx.

\n
", "Markscheme": "
\n

dydx+2yx=ln2xx2                 (M1)

\n

attempt to find integrating factor                 (M1)

\n

e2xdx=e2lnx=x2                 (A1)

\n

x2dydx+2xy=ln2x

\n

ddxx2y=ln2x

\n

x2y=ln2xdx

\n

attempt to use integration by parts                 (M1)

\n

x2y=xln2x-x+c                 A1

\n

y=ln2xx-1x+cx2

\n

substituting x=12, y=4 into an integrated equation involving c                 M1

\n

4=0-2+4c

\n

c=32

\n

y=ln2xx-1x+32x2                 A1

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21N.1.AHL.TZ0.8", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-16-integration-by-substitution-parts-and-repeated-parts" ] }, { "Question": "
\n

Solve the equation log3x=12log23+log34x3, where x>0.

\n
", "Markscheme": "
\n

attempt to use change the base                (M1)

\n

log3x=log322+log34x3

\n

attempt to use the power rule                (M1)

\n

log3x=log32+log34x3

\n

attempt to use product or quotient rule for logs, lna+lnb=lnab                (M1)

\n

log3x=log342x3

\n


Note:
The M marks are for attempting to use the relevant log rule and may be applied in any order and at any time during the attempt seen.

\n


x=42x3

\n

x=32x6

\n

x5=132                (A1)

\n

x=12                A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21N.1.AHL.TZ0.3", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-7-laws-of-exponents-and-logs" ] }, { "Question": "
\n

Consider the expression 11+ax-1-x where a, a0.

\n

The binomial expansion of this expression, in ascending powers of x, as far as the term in x2 is 4bx+bx2, where b.

\n
\n

Find the value of a and the value of b.

\n
[6]
\n
a.
\n
\n

State the restriction which must be placed on x for this expansion to be valid.

\n
[1]
\n
b.
\n
", "Markscheme": "
\n

attempt to expand binomial with negative fractional power                 (M1)

\n

11+ax=1+ax-12=1-ax2+3a2x28+                A1

\n

1-x=1-x12=1-x2-x28+                A1

\n

11+ax-1-x=1-a2x+3a2+18x2+

\n

attempt to equate coefficients of x or x2                 (M1)

\n

x :  1-a2=4b;  x2 : 3a2+18=b

\n

attempt to solve simultaneously                 (M1)

\n

a=-13, b=16                A1

\n

 

\n

[6 marks]

\n
a.
\n
\n

x<1              A1

\n

 

\n

[1 mark]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.1.AHL.TZ0.9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

Let \nf\n(\nx\n)\n=\ncos\n\nx\n.

\n
\n

Let \ng\n(\nx\n)\n=\n\n\nx\nk\n\n\n, where \nk\n\n\n\n\nZ\n\n+\n\n\n.

\n
\n

Let \nk\n=\n21\n and \nh\n(\nx\n)\n=\n\n(\n\n\n\nf\n\n(\n19\n)\n\n\n\n(\nx\n)\n×\n\n\ng\n\n(\n19\n)\n\n\n\n(\nx\n)\n\n)\n\n.

\n
\n

(i)     Find the first four derivatives of \nf\n(\nx\n)\n.

\n

(ii)     Find \n\n\nf\n\n(\n19\n)\n\n\n\n(\nx\n)\n.

\n
[4]
\n
a.
\n
\n

(i)     Find the first three derivatives of \ng\n(\nx\n)\n.

\n

(ii)     Given that \n\n\ng\n\n(\n19\n)\n\n\n\n(\nx\n)\n=\n\n\nk\n!\n\n\n(\nk\n\np\n)\n!\n\n\n(\n\n\nx\n\nk\n\n19\n\n\n\n)\n, find \np\n.

\n
[5]
\n
b.
\n
\n

(i)     Find \n\nh\n\n\n(\nx\n)\n.

\n

(ii)     Hence, show that \n\nh\n\n\n(\nπ\n)\n=\n\n\n\n21\n!\n\n2\n\n\n\nπ\n2\n\n\n.

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

(i)     \n\nf\n\n\n(\nx\n)\n=\n\nsin\n\nx\n,\n\n \n\n\nf\n\n\n(\nx\n)\n=\n\ncos\n\nx\n,\n\n \n\n\n\nf\n\n(\n3\n)\n\n\n\n(\nx\n)\n=\nsin\n\nx\n,\n\n \n\n\n\nf\n\n(\n4\n)\n\n\n\n(\nx\n)\n=\ncos\n\nx\n     A2     N2

\n

(ii)     valid approach     (M1)

\n

eg\n\n\n\n\n\nrecognizing that 19 is one less than a multiple of 4, \n\n\nf\n\n(\n19\n)\n\n\n\n(\nx\n)\n=\n\n\nf\n\n(\n3\n)\n\n\n\n(\nx\n)\n

\n

\n\n\nf\n\n(\n19\n)\n\n\n\n(\nx\n)\n=\nsin\n\nx\n     A1     N2

\n

[4 marks]

\n
a.
\n
\n

(i)     \n\ng\n\n\n(\nx\n)\n=\nk\n\n\nx\n\nk\n\n1\n\n\n\n

\n

\n\ng\n\n\n(\nx\n)\n=\nk\n(\nk\n\n1\n)\n\n\nx\n\nk\n\n2\n\n\n\n,\n\n \n\n\n\ng\n\n(\n3\n)\n\n\n\n(\nx\n)\n=\nk\n(\nk\n\n1\n)\n(\nk\n\n2\n)\n\n\nx\n\nk\n\n3\n\n\n\n     A1A1     N2

\n

(ii)     METHOD 1

\n

correct working that leads to the correct answer, involving the correct expression for the 19th derivative     A2

\n

eg\n\n\n\n\n\n\nk\n(\nk\n\n1\n)\n(\nk\n\n2\n)\n\n(\nk\n\n18\n)\n×\n\n\n(\nk\n\n19\n)\n!\n\n\n(\nk\n\n19\n)\n!\n\n\n,\n\n\n\n \n\nk\n\n\n\n\nP\n\n19\n\n\n\n

\n

\np\n=\n19\n (accept \n\n\nk\n!\n\n\n(\nk\n\n19\n)\n!\n\n\n\n\nx\n\nk\n\n19\n\n\n\n)     A1     N1

\n

METHOD 2

\n

correct working involving recognizing patterns in coefficients of first three derivatives (may be seen in part (b)(i)) leading to a general rule for 19th coefficient     A2

\n

eg\n\n\n\n\n\n\n\ng\n\n\n=\n2\n!\n\n(\n\n\n\n\nk\n\n\n\n\n2\n\n\n\n\n)\n\n,\n\n \n\nk\n(\nk\n\n1\n)\n(\nk\n\n2\n)\n=\n\n\nk\n!\n\n\n(\nk\n\n3\n)\n!\n\n\n,\n\n \n\n\n\ng\n\n(\n3\n)\n\n\n\n(\nx\n)\n\n\n=\nk\n\n\n\n\nP\n3\n\n\n(\n\n\nx\n\nk\n\n3\n\n\n\n)\n

\n

\n\n\ng\n\n(\n19\n)\n\n\n\n(\nx\n)\n=\n19\n!\n\n(\n\n\n\n\nk\n\n\n\n\n\n19\n\n\n\n\n\n)\n\n,\n\n \n\n19\n!\n×\n\n\nk\n!\n\n\n(\nk\n\n19\n)\n!\n×\n19\n!\n\n\n,\n\n\n\n \n\nk\n\n\n\n\nP\n\n19\n\n\n\n

\n

\np\n=\n19\n (accept \n\n\nk\n!\n\n\n(\nk\n\n19\n)\n!\n\n\n\n\nx\n\nk\n\n19\n\n\n\n)     A1     N1

\n

[5 marks]

\n
b.
\n
\n

(i)     valid approach using product rule     (M1)

\n

eg\n\n\n\n\n\n\nu\n\nv\n\n\n+\nv\n\nu\n\n\n,\n\n \n\n\n\nf\n\n(\n19\n)\n\n\n\n\n\ng\n\n(\n20\n)\n\n\n\n+\n\n\nf\n\n(\n20\n)\n\n\n\n\n\ng\n\n(\n19\n)\n\n\n\n

\n

correct 20th derivatives (must be seen in product rule)     (A1)(A1)

\n

eg\n\n\n\n\n\n\n\n\ng\n\n(\n20\n)\n\n\n\n(\nx\n)\n=\n\n\n21\n!\n\n\n(\n21\n\n20\n)\n!\n\n\nx\n,\n\n \n\n\n\nf\n\n(\n20\n)\n\n\n\n(\nx\n)\n=\ncos\n\nx\n

\n

\n\nh\n\n\n(\nx\n)\n=\nsin\n\nx\n(\n21\n!\nx\n)\n+\ncos\n\nx\n\n(\n\n\n\n21\n!\n\n2\n\n\n\nx\n2\n\n\n\n)\n\n\n \n\n\n(\n\n\naccept \n\nsin\n\nx\n\n(\n\n\n\n21\n!\n\n\n1\n!\n\n\nx\n\n)\n\n+\ncos\n\nx\n\n(\n\n\n\n21\n!\n\n\n2\n!\n\n\n\n\nx\n2\n\n\n\n)\n\n\n)\n\n    A1     N3

\n

(ii)     substituting \nx\n=\nπ\n (seen anywhere)     (A1)

\n

eg\n\n\n\n\n\n\n\n\nf\n\n(\n19\n)\n\n\n\n(\nπ\n)\n\n\ng\n\n(\n20\n)\n\n\n\n(\nπ\n)\n+\n\n\nf\n\n(\n20\n)\n\n\n\n(\nπ\n)\n\n\ng\n\n(\n19\n)\n\n\n\n(\nπ\n)\n,\n\n \n\nsin\n\nπ\n\n\n21\n!\n\n\n1\n!\n\n\nπ\n+\ncos\n\nπ\n\n\n21\n!\n\n\n2\n!\n\n\n\n\nπ\n2\n\n\n

\n

evidence of one correct value for \nsin\n\nπ\n or \ncos\n\nπ\n (seen anywhere)     (A1)

\n

eg\n\n\n\n\n\n\nsin\n\nπ\n=\n0\n,\n\n \n\ncos\n\nπ\n=\n\n1\n

\n

evidence of correct values substituted into \n\nh\n\n\n(\nπ\n)\n     A1

\n

eg\n\n\n\n\n\n\n21\n!\n(\nπ\n)\n\n(\n\n0\n\n\nπ\n\n2\n!\n\n\n\n)\n\n,\n\n \n\n21\n!\n(\nπ\n)\n\n(\n\n\n\nπ\n2\n\n\n)\n\n,\n\n \n\n0\n+\n(\n\n1\n)\n\n\n21\n!\n\n2\n\n\n\nπ\n2\n\n\n

\n

 

\n

Note: If candidates write only the first line followed by the answer, award A1A0A0.

\n

 

\n

\n\n\n\n21\n!\n\n2\n\n\n\nπ\n2\n\n\n     AG     N0

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "16N.1.SL.TZ0.S_10", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-3-differentiating-polynomials-n-e-z" ] }, { "Question": "
\n

Consider \nf\n(\nx\n)\n=\nlog\n\nk\n(\n6\nx\n\n3\n\n\nx\n2\n\n\n)\n, for \n0\n<\nx\n<\n2\n, where \nk\n>\n0\n.

\n

The equation \nf\n(\nx\n)\n=\n2\n has exactly one solution. Find the value of \nk\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 – using discriminant

\n

correct equation without logs     (A1)

\n

eg\n\n\n\n\n\n\n6\nx\n\n3\n\n\nx\n2\n\n\n=\n\n\nk\n2\n\n\n

\n

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\n3\n\n\nx\n2\n\n\n+\n6\nx\n\n\n\nk\n2\n\n\n=\n0\n,\n\n \n\n3\n\n\nx\n2\n\n\n\n6\nx\n+\n\n\nk\n2\n\n\n=\n0\n

\n

recognizing discriminant must be zero (seen anywhere)     M1

\n

eg\n\n\n\n\n\n\nΔ\n=\n0\n

\n

correct discriminant     (A1)

\n

eg\n\n\n\n\n\n\n\n\n6\n2\n\n\n\n4\n(\n\n3\n)\n(\n\n\n\nk\n2\n\n\n)\n,\n\n \n\n36\n\n12\n\n\nk\n2\n\n\n=\n0\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n12\n\n\nk\n2\n\n\n=\n36\n,\n\n \n\n\n\nk\n2\n\n\n=\n3\n

\n

\nk\n=\n\n3\n\n     A2     N2

\n

METHOD 2 – completing the square

\n

correct equation without logs     (A1)

\n

eg\n\n\n\n\n\n\n6\nx\n\n3\n\n\nx\n2\n\n\n=\n\n\nk\n2\n\n\n

\n

valid approach to complete the square     (M1)

\n

eg\n\n\n\n\n\n\n3\n(\n\n\nx\n2\n\n\n\n2\nx\n+\n1\n)\n=\n\n\n\nk\n2\n\n\n+\n3\n,\n\n \n\n\n\nx\n2\n\n\n\n2\nx\n+\n1\n\n1\n+\n\n\n\n\nk\n2\n\n\n\n3\n\n=\n0\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n3\n\n(\nx\n\n1\n\n)\n2\n\n\n=\n\n\n\nk\n2\n\n\n+\n3\n,\n\n \n\n\n(\nx\n\n1\n\n)\n2\n\n\n\n1\n+\n\n\n\n\nk\n2\n\n\n\n3\n\n=\n0\n

\n

recognizing conditions for one solution     M1

\n

eg\n\n\n\n\n\n\n\n(\nx\n\n1\n\n)\n2\n\n\n=\n0\n,\n\n \n\n\n1\n+\n\n\n\n\nk\n2\n\n\n\n3\n\n=\n0\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n\n\n\n\nk\n2\n\n\n\n3\n\n=\n1\n,\n\n \n\n\n\nk\n2\n\n\n=\n3\n

\n

\nk\n=\n\n3\n\n     A2     N2

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17N.1.SL.TZ0.S_7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

Let \n\nf\n\n\n\n(\nx\n)\n\n=\n\n(\n\n\ncos\n\n\n2\nx\n\n)\n\n\n(\n\n\nsin\n\n\n6\nx\n\n)\n\n, for 0 ≤ \nx\n ≤ 1.

\n
\n

Sketch the graph of \n\n\nf\n\n\n\n on the grid below:

\n

\n
[3]
\n
a.
\n
\n

Find the \nx\n-coordinates of the points of inflexion of the graph of \nf\n.

\n
[3]
\n
b.
\n
\n

Hence find the values of \nx\n for which the graph of \nf\n is concave-down.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

  A1A1A1 N3

\n

Note: Only if the shape is approximately correct with exactly 2 maximums and 1 minimum on the interval 0 ≤ \nx\n ≤ 0, award the following:
A1 for correct domain with both endpoints within circle and oval.
A1 for passing through the other \nx\n-intercepts within the circles.
A1 for passing through the three turning points within circles (ignore \nx\n-intercepts and extrema outside of the domain).

\n

[3 marks]

\n
a.
\n
\n

evidence of reasoning (may be seen on graph)      (M1)

\n

eg  \n\nf\n\n\n=\n0\n,  (0.524, 0),  (0.785, 0)

\n

0.523598,  0.785398

\n

\nx\n=\n0.524\n\n\n\n(\n\n=\n\nπ\n6\n\n\n)\n\n,  \nx\n=\n0.785\n\n\n\n(\n\n=\n\nπ\n4\n\n\n)\n\n     A1A1  N3

\n

Note: Award M1A1A0 if any solution outside domain (eg \nx\n=\n0\n) is also included.

\n

[3 marks]

\n
b.
\n
\n

\n0.524\n<\nx\n<\n0.785\n\n\n\n\n(\n\n\nπ\n6\n\n<\nx\n<\n\nπ\n4\n\n\n)\n\n     A2  N2

\n

Note: Award A1 if any correct interval outside domain also included, unless additional solutions already penalized in (b).
Award A0 if any incorrect intervals are also included.

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.SL.TZ1.S_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

In Lucy’s music academy, eight students took their piano diploma examination and achieved scores out of 150. For her records, Lucy decided to record the average number of hours per week each student reported practising in the weeks prior to their examination. These results are summarized in the table below.

\n

\n
\n

Find Pearson’s product-moment correlation coefficient, r, for these data.

\n
[2]
\n
a.
\n
\n

The relationship between the variables can be modelled by the regression equation D=ah+b. Write down the value of a and the value of b.

\n
[1]
\n
b.
\n
\n

One of these eight students was disappointed with her result and wished she had practised more. Based on the given data, determine how her score could have been expected to alter had she practised an extra five hours per week.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

use of GDC to give                          (M1)

\n

r=0.883529

\n

r=0.884                         A1

\n


Note:
Award the (M1) for any correct value of r, a, b or r2=0.780624 seen in part (a) or part (b).

\n


[2 marks]

\n
a.
\n
\n

a=1.36609 , b=64.5171

\n

a=1.37 , b=64.5                       A1

\n



[1 mark]

\n
b.
\n
\n

attempt to find their difference                       (M1)

\n

5×1.36609  OR  1.36609h+5+64.5171-1.36609h+64.5171

\n

6.83045

\n

=6.83  6.85 from 1.37

\n

the student could have expected her score to increase by 7 marks.                       A1

\n


Note: Accept an increase of 6, 6.83 or 6.85.

\n


[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21N.2.SL.TZ0.1", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-4-pearsons-scatter-diagrams-eqn-of-y-on-x" ] }, { "Question": "
\n

Consider the function fx=e-x2-0.5, for -2x2.

\n
\n

Find the values of x for which f(x)=0.

\n
[2]
\n
a.
\n
\n

Sketch the graph of f on the following grid.

\n

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

x=-0.832554, x=0.832554

\n

x=-0.833, x=0.833                       A1A1

\n


[2 marks]

\n
a.
\n
\n

                       A1A1A1

\n


Note: Award A1 for approximately correct shape. Only if this mark is awarded, award A1 for approximately correct roots and maximum point and A1 for approximately correct endpoints. 
Allow -1<x-0.8,  0.8x<1 for roots, x=0, 0.4y0.6 for maximum and x=±2, -0.6y-0.4 for endpoints.

\n


[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.2.SL.TZ0.2", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-3-graphing" ] }, { "Question": "
\n

The population of fish in a lake is modelled by the function

\n

\nf\n\n(\nt\n)\n\n=\n\n\n1000\n\n\n1\n+\n24\n\n\n\ne\n\n\n\n0.2\nt\n\n\n\n\n\n, 0 ≤ \nt\n ≤ 30 , where \nt\n is measured in months.

\n
\n

Find the population of fish at \nt\n = 10.

\n
[2]
\n
a.
\n
\n

Find the rate at which the population of fish is increasing at \nt\n = 10.

\n
[2]
\n
b.
\n
\n

Find the value of \nt\n for which the population of fish is increasing most rapidly.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach      (M1)

\n

eg   \nf\n(10)

\n

235.402

\n

235 (fish) (must be an integer)     A1 N2

\n

[2 marks]

\n
a.
\n
\n

recognizing rate of change is derivative     (M1)

\n

eg  rate = \n\n\nf\n\n\n\n\n\n\nf\n\n\n\n(10) , sketch of \n\n\nf\n\n\n\n ,  35 (fish per month)

\n

35.9976

\n

36.0 (fish per month)     A1 N2

\n

[2 marks]

\n
b.
\n
\n

valid approach    (M1)

\n

eg   maximum of \n\n\nf\n\n\n\n ,   \n\n\nf\n\n\n\n = 0

\n

15.890

\n

15.9 (months)     A1 N2

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "19M.2.SL.TZ2.S_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

Consider a triangle ABC, where AC=12, CB=7 and BA^C=25°.

\n

Find the smallest possible perimeter of triangle ABC.

\n
", "Markscheme": "
\n

EITHER

\n

attempt to use cosine rule               (M1)

\n

122+AB2-2×12×cos25°×AB=72  OR  AB2-21.7513AB+95=0                 (A1)

\n

at least one correct value for AB                 (A1)

\n

AB=6.05068  OR  AB=15.7007

\n

using their smaller value for AB to find minimum perimeter               (M1)

\n

12+7+6.05068

\n


OR

\n

attempt to use sine rule               (M1)

\n

sinB12=sin25°7  OR  sinB=0.724488  OR  B^=133.573°  OR  B^=46.4263°                 (A1)

\n

at least one correct value for C                 (A1)

\n

C^=21.4263°  OR  C^=108.573°

\n

using their acute value for C^ to find minimum perimeter               (M1)

\n

12+7+122+72-2×12×7cos21.4263°  OR  12+7+7sin21.4263°sin25°

\n


THEN

\n

25.0506

\n

minimum perimeter =25.1.                       A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "21N.2.SL.TZ0.3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A factory manufactures lamps. It is known that the probability that a lamp is found to be defective is 0.05. A random sample of 30 lamps is tested.

\n
\n

Find the probability that there is at least one defective lamp in the sample.

\n
[3]
\n
a.
\n
\n

Given that there is at least one defective lamp in the sample, find the probability that there are at most two defective lamps.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

recognize that the variable has a Binomial distribution              (M1)

\n

X~B30,0.05

\n

attempt to find PX1              (M1)

\n

1-PX=0  OR  1-0.9530  OR  1-0.214638  OR  0.785361

\n


Note: The two M marks are independent of each other.

\n


PX1=0.785                  A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

recognition of conditional probability             (M1)

\n

PX2X1  OR  Pat most 2 defective|at least 1 defective

\n


Note: Recognition must be shown in context either in words or symbols but not just PAB.

\n


P1X2PX1  OR  PX=1+PX=2PX1              (A1)

\n

0.5975400.785361  OR  0.812178-0.2146380.785361  OR  0.338903+0.2586360.785361              (A1)

\n

=0.760847

\n

PX2X1=0.761                 A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.2.SL.TZ0.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Find \n\n\nx\n\n\n\ne\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n\nd\n\nx\n\n.

\n
[4]
\n
a.
\n
\n

Find \nf\n(\nx\n)\n, given that \n\nf\n\n\n(\nx\n)\n=\nx\n\n\n\ne\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n and \nf\n(\n\n1\n)\n=\n3\n.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach to set up integration by substitution/inspection     (M1)

\n

eg\n\n\n\n\n\n\nu\n=\n\n\nx\n2\n\n\n\n1\n,\n\n d\n\nu\n=\n2\nx\n,\n\n \n\n\n\n2\nx\n\n\n\ne\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n\nd\n\nx\n\n

\n

correct expression     (A1)

\n

eg\n\n\n\n\n\n\n\n1\n2\n\n\n\n2\nx\n\n\n\ne\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n\nd\n\nx\n,\n\n \n\n\n1\n2\n\n\n\n\n\n\ne\n\nu\n\n\n\nd\n\nu\n\n\n

\n

\n\n1\n2\n\n\n\n\ne\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n+\nc\n     A2     N4

\n

 

\n

Notes: Award A1 if missing “\n+\nc\n”.

\n

 

\n

[4 marks]

\n
a.
\n
\n

substituting \nx\n=\n\n1\n into their answer from (a)     (M1)

\n

eg\n\n\n\n\n\n\n\n1\n2\n\n\n\n\ne\n\n0\n\n\n,\n\n \n\n\n1\n2\n\n\n\n\ne\n\n\n1\n\n1\n\n\n\n=\n3\n

\n

correct working     (A1)

\n

eg\n\n\n\n\n\n\n\n1\n2\n\n+\nc\n=\n3\n,\n\n \n\nc\n=\n2.5\n

\n

\nf\n(\nx\n)\n=\n\n1\n2\n\n\n\n\ne\n\n\n\n\nx\n2\n\n\n\n1\n\n\n\n+\n2.5\n     A1     N2

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "17M.1.SL.TZ1.S_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

Let \n\nf\n\n\n(\nx\n)\n=\n\n\n3\n\n\nx\n2\n\n\n\n\n\n\n\n(\n\n\nx\n3\n\n\n+\n1\n)\n\n5\n\n\n\n\n. Given that \nf\n(\n0\n)\n=\n1\n, find \nf\n(\nx\n)\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach     (M1)

\n

eg\n\n\n\n\n\n\n\n\n\nf\n\n\n\nd\n\nx\n,\n\n \n\n\n\n\n\n3\n\n\nx\n2\n\n\n\n\n\n\n\n(\n\n\nx\n3\n\n\n+\n1\n)\n\n5\n\n\n\n\n\nd\n\nx\n\n\n

\n

correct integration by substitution/inspection     A2

\n

eg\n\n\n\n\n\n\nf\n(\nx\n)\n=\n\n\n1\n4\n\n\n(\n\n\nx\n3\n\n\n+\n1\n\n)\n\n\n4\n\n\n\n+\nc\n,\n\n \n\n\n\n\n1\n\n\n4\n\n\n\n(\n\n\nx\n3\n\n\n+\n1\n)\n\n4\n\n\n\n\n

\n

correct substitution into their integrated function (must include \nc\n)     M1

\n

eg\n\n\n\n\n\n\n1\n=\n\n\n\n1\n\n\n4\n\n\n\n(\n\n\n0\n3\n\n\n+\n1\n)\n\n4\n\n\n\n\n+\nc\n,\n\n \n\n\n\n1\n4\n\n+\nc\n=\n1\n

\n

 

\n

Note:     Award M0 if candidates substitute into \n\nf\n\n\n or \n\nf\n\n\n.

\n

 

\n

\nc\n=\n\n5\n4\n\n     (A1)

\n

\nf\n(\nx\n)\n=\n\n\n1\n4\n\n\n(\n\n\nx\n3\n\n\n+\n1\n\n)\n\n\n4\n\n\n\n+\n\n5\n4\n\n\n \n\n\n(\n\n=\n\n\n\n1\n\n\n4\n\n\n\n(\n\n\nx\n3\n\n\n+\n1\n)\n\n4\n\n\n\n\n+\n\n5\n4\n\n,\n\n \n\n\n\n5\n\n\n\n(\n\n\nx\n3\n\n\n+\n1\n)\n\n4\n\n\n\n1\n\n\n4\n\n\n\n(\n\n\nx\n3\n\n\n+\n1\n)\n\n4\n\n\n\n\n\n)\n\n     A1     N4

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "17M.1.SL.TZ2.S_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

Let \nf\n\n(\nx\n)\n\n=\n\n\n6\n\n2\nx\n\n\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n\n\n. The following diagram shows part of the graph of \nf\n.

\n

\n

The region R is enclosed by the graph of \nf\n, the \nx\n-axis, and the \ny\n-axis. Find the area of R.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

METHOD 1 (limits in terms of \nx\n)

\n

valid approach to find \nx\n-intercept      (M1)

\n

eg   \nf\n\n(\nx\n)\n\n=\n0\n,  \n\n\n6\n\n2\nx\n\n\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n\n\n=\n0\n,  \n6\n\n2\nx\n=\n0\n

\n

\nx\n-intercept is 3      (A1)

\n

valid approach using substitution or inspection      (M1)

\n

eg   \nu\n=\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n,  \n\n\n0\n3\n\n\n\n\n6\n\n2\nx\n\n\n\nu\n\n\n\n\n\nd\n\nx\n,  \n\nd\n\nu\n=\n6\n\n2\nx\n\n\n\n\n1\n\n\nu\n\n\n\n\n,  \n2\n\n\nu\n\n\n1\n2\n\n\n\n\n,

\n

\nu\n=\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n,   \n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n\n(\n\n6\n\n2\nx\n\n)\n\n\n1\n2\n\n\n\n\n(\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n)\n\n\n\n\n1\n2\n\n\n\n\n,  \n\n2\n\n\nd\n\nu\n,  \n2\nu\n

\n

\n\n\nf\n\n(\nx\n)\n\n\n\n\nd\n\nx\n=\n2\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n      (A2)

\n

substituting both of their limits into their integrated function and subtracting      (M1)

\n

eg   \n2\n\n16\n+\n6\n\n(\n3\n)\n\n\n\n\n3\n2\n\n\n\n\n2\n\n16\n+\n6\n\n\n\n\n(\n0\n)\n\n\n2\n\n\n\n\n\n0\n2\n\n\n\n,  \n2\n\n16\n+\n18\n\n9\n\n\n2\n\n16\n\n

\n

Note: Award M0 if they substitute into original or differentiated function. Do not accept only “– 0” as evidence of substituting lower limit.

\n

 

\n

correct working      (A1)

\n

eg   \n2\n\n25\n\n\n2\n\n16\n\n,  \n10\n\n8\n

\n

area = 2      A1 N2

\n

 

\n

 

\n

METHOD 2 (limits in terms of \nu\n)

\n

valid approach to find \nx\n-intercept      (M1)

\n

eg   \nf\n\n(\nx\n)\n\n=\n0\n,  \n\n\n6\n\n2\nx\n\n\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n\n\n=\n0\n,  \n6\n\n2\nx\n=\n0\n

\n

\nx\n-intercept is 3      (A1)

\n

valid approach using substitution or inspection      (M1)

\n

eg   \nu\n=\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n,  \n\n\n0\n3\n\n\n\n\n6\n\n2\nx\n\n\n\nu\n\n\n\n\n\nd\n\nx\n,  \n\nd\n\nu\n=\n6\n\n2\nx\n\n\n\n\n1\n\n\nu\n\n\n\n\n

\n

\nu\n=\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n,   \n\n\n\nd\n\nu\n\n\n\nd\n\nx\n\n\n=\n\n(\n\n6\n\n2\nx\n\n)\n\n\n1\n2\n\n\n\n\n(\n\n16\n+\n6\nx\n\n\n\nx\n2\n\n\n\n)\n\n\n\n\n1\n2\n\n\n\n\n,  \n\n2\n\n\nd\n\nu\n

\n

correct integration      (A2)

\n

eg   \n\n\n\n1\n\n\nu\n\n\n\n\n\n\nd\n\nu\n=\n2\n\n\nu\n\n\n1\n2\n\n\n\n\n,   \n\n2\n\n\nd\n\nu\n=\n2\nu\n

\n

both correct limits for \nu\n      (A1)

\n

eg   \nu\n = 16 and \nu\n = 25,  \n\n\n\n16\n\n\n25\n\n\n\n\n1\n\n\nu\n\n\n\n\nd\n\nu\n\n,   \n\n\n[\n\n2\n\n\nu\n\n\n1\n2\n\n\n\n\n\n]\n\n\n16\n\n\n25\n\n\n,   \nu\n = 4 and \nu\n = 5,  \n\n\n4\n5\n\n2\n\n\nd\n\nu\n,   \n\n\n[\n\n2\nu\n\n]\n\n4\n5\n\n

\n

substituting both of their limits for \nu\n (do not accept 0 and 3) into their integrated function and subtracting     (M1)

\n

eg   \n2\n\n25\n\n\n2\n\n16\n\n,  \n10\n\n8\n

\n

Note: Award M0 if they substitute into original or differentiated function, or if they have not attempted to find limits for \nu\n.

\n

 

\n

area = 2      A1 N2

\n

 

\n

[8 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "18N.1.SL.TZ0.S_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

The following diagram shows a semicircle with centre O and radius r. Points P, Q and R lie on the circumference of the circle, such that PQ=2r and RO^Q=θ, where 0<θ<π.

\n

\n
\n

Given that the areas of the two shaded regions are equal, show that θ=2sinθ.

\n
[5]
\n
a.
\n
\n

Hence determine the value of θ.

\n
[1]
\n
b.
\n
", "Markscheme": "
\n

attempt to find the area of either shaded region in terms of r and θ             (M1)

\n


Note: Do not award M1 if they have only copied from the booklet and not applied to the shaded area.

\n


Area of segment =12r2θ-12r2sinθ                 A1

\n

Area of triangle =12r2sinπ-θ                 A1

\n

correct equation in terms of θ only                 (A1)

\n

θ-sinθ=sinπ-θ

\n

θ-sinθ=sinθ                 A1

\n

θ=2sinθ                 AG

\n


Note: Award a maximum of M1A1A0A0A0 if a candidate uses degrees (i.e., 12r2sin180°-θ), even if later work is correct.

\n

Note: If a candidate directly states that the area of the triangle is 12r2sinθ, award a maximum of M1A1A0A1A1.

\n


[5 marks]

\n
a.
\n
\n

θ=1.89549

\n

θ=1.90                 A1

\n


Note: Award A0 if there is more than one solution. Award A0 for an answer in degrees.

\n


[1 mark]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "21N.2.SL.TZ0.5", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

Let \n\nf\n\n\n(\nx\n)\n=\n\n\nsin\n3\n\n\n(\n2\nx\n)\ncos\n\n(\n2\nx\n)\n. Find \nf\n(\nx\n)\n, given that \nf\n\n(\n\n\nπ\n4\n\n\n)\n\n=\n1\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

evidence of integration     (M1)

\n

eg\n\n\n\n\n\n\n\n\n\nf\n\n\n(\nx\n)\n\nd\n\nx\n\n

\n

correct integration (accept missing \nC\n)     (A2)

\n

eg\n\n\n\n\n\n\n\n1\n2\n\n×\n\n\n\n\n\nsin\n\n4\n\n\n(\n2\nx\n)\n\n4\n\n,\n\n \n\n\n1\n8\n\n\n\nsin\n4\n\n\n(\n2\nx\n)\n+\nC\n

\n

substituting initial condition into their integrated expression (must have \n+\nC\n)     M1

\n

eg\n\n\n\n\n\n\n1\n=\n\n1\n8\n\n\n\nsin\n4\n\n\n\n(\n\n\nπ\n2\n\n\n)\n\n+\nC\n

\n

 

\n

Note: Award M0 if they substitute into the original or differentiated function.

\n

 

\n

recognizing \nsin\n\n\n(\n\n\nπ\n2\n\n\n)\n\n=\n1\n     (A1)

\n

eg\n\n\n\n\n\n\n1\n=\n\n1\n8\n\n\n(\n1\n\n)\n4\n\n\n+\nC\n

\n

\nC\n=\n\n7\n8\n\n    (A1)

\n

\nf\n(\nx\n)\n=\n\n1\n8\n\n\n\nsin\n4\n\n\n(\n2\nx\n)\n+\n\n7\n8\n\n     A1     N5

\n

[7 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "16N.1.SL.TZ0.S_6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

The derivative of a function \nf\n is given by \n\nf\n\n\n(\nx\n)\n=\n2\n\n\n\ne\n\n\n\n3\nx\n\n\n\n. The graph of \nf\n passes through \n\n(\n\n\n1\n3\n\n\n,\n\n\n\n5\n\n)\n\n.

\n

Find \nf\n(\nx\n)\n.

\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

recognizing to integrate   (M1)

\n

eg   \n\n\n\nf\n\n\n\n,  \n\n\n2\n\n\n\ne\n\n\n\n3\nx\n\n\n\n\nd\n\nx\n\n,  \n\nd\n\nu\n=\n\n3\n

\n

correct integral (do not penalize for missing +\nC\n)     (A2)

\n

eg   \n\n\n2\n3\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n+\nC\n

\n

substituting \n\n(\n\n\n1\n3\n\n\n,\n\n\n\n5\n\n)\n\n (in any order) into their integrated expression (must have +\nC\n)      M1

\n

eg   \n\n\n2\n3\n\n\n\n\ne\n\n\n\n3\n\n(\n\n1\n\n/\n\n3\n\n)\n\n\n\n\n+\nC\n=\n5\n

\n

Note: Award M0 if they substitute into original or differentiated function.

\n

\nf\n(\nx\n)\n=\n\n\n2\n3\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n+\n5\n+\n\n2\n3\n\n\n\n\ne\n\n\n\n1\n\n\n\n (or any equivalent form, eg \n\n\n2\n3\n\n\n\n\ne\n\n\n\n3\nx\n\n\n\n+\n5\n\n\n2\n\n\n3\n\ne\n\n\n\n)               A1   N4

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "19M.1.SL.TZ1.S_5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

A particle moves along a straight line so that its velocity, \nv\n m s−1, after \nt\n seconds is given by \nv\n\n(\nt\n)\n\n=\n\n\n1.4\nt\n\n\n\n2.7\n, for 0 ≤ \nt\n ≤ 5.

\n
\n

Find when the particle is at rest.

\n
[2]
\n
a.
\n
\n

Find the acceleration of the particle when \nt\n=\n2\n.

\n
[2]
\n
b.
\n
\n

Find the total distance travelled by the particle.

\n
[3]
\n
c.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

valid approach      (M1)

\n

eg     \nv\n\n(\nt\n)\n\n=\n0\n, sketch of graph

\n

2.95195

\n

\nt\n=\n\nlo\n\n\n\n\ng\n\n\n1.4\n\n\n\n2.7\n  (exact), \nt\n=\n2.95\n (s)      A1 N2

\n

 

\n

[2 marks]

\n
a.
\n
\n

valid approach      (M1)

\n

eg     \na\n\n(\nt\n)\n\n=\n\nv\n\n\n\n(\nt\n)\n\n,   \n\nv\n\n\n\n(\n2\n)\n\n

\n

0.659485

\n

\na\n\n(\n2\n)\n\n = 1.96 ln 1.4   (exact),  \na\n\n(\n2\n)\n\n = 0.659 (m s−2)      A1 N2

\n

 

\n

[2 marks]

\n
b.
\n
\n

correct approach      (A1)

\n

eg    \n\n\n0\n5\n\n\n\n|\n\nv\n\n(\nt\n)\n\n\n|\n\n\n\n\nd\n\nt\n\n\n\n0\n\n2.95\n\n\n\n\n(\n\n\nv\n\n(\nt\n)\n\n\n)\n\n\n\n\nd\n\nt\n+\n\n\n\n295\n\n5\n\n\nv\n\n(\nt\n)\n\n\n\n\nd\n\nt\n

\n

5.3479

\n

distance = 5.35 (m)      A2 N3

\n

 

\n

[3 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "18N.2.SL.TZ0.S_4", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems" ] }, { "Question": "
\n

Points A and P lie on opposite banks of a river, such that AP is the shortest distance across the river. Point B represents the centre of a city which is located on the riverbank. PB=215km, AP=65km and AP^B=90°.

\n

The following diagram shows this information.

\n

\n

A boat travels at an average speed of 42km h-1. A bus travels along the straight road between P and B at an average speed of 84km h-1.

\n
\n

Find the travel time, in hours, from A to B given that

\n
\n

There is a point D, which lies on the road from P to B, such that BD=xkm. The boat travels from A to D, and the bus travels from D to B.

\n
\n

An excursion involves renting the boat and the bus. The cost to rent the boat is $200 per hour, and the cost to rent the bus is $150 per hour.

\n
\n

the boat is taken from A to P, and the bus from P to B.

\n
[2]
\n
a.i.
\n
\n

the boat travels directly to B.

\n
[2]
\n
a.ii.
\n
\n

Find an expression, in terms of x for the travel time T, from A to B, passing through D.

\n
[3]
\n
b.i.
\n
\n

Find the value of x so that T is a minimum.

\n
[2]
\n
b.ii.
\n
\n

Write down the minimum value of T.

\n
[1]
\n
b.iii.
\n
\n

Find the new value of x so that the total cost C to travel from A to B via D is a minimum.

\n
[3]
\n
c.i.
\n
\n

Write down the minimum total cost for this journey.

\n
[1]
\n
c.ii.
\n
", "Markscheme": "
\n

AP42  OR  21584  OR  6542+21584                 (M1)

\n

time =4.10714 (hours)

\n

time =4.11 (hours)                 A1

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

AB=2152+652=224.610                 (A1)

\n

time =5.34787 (hours)

\n

time =5.35 (hours)                 A1

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

AD=215-x2+652                 (A1)

\n

t=215-x2+65242                 (A1)

\n

T=215-x2+65242+x84=x2-430x+5045042+x84                 A1

\n

 

\n

[3 marks]

\n
b.i.
\n
\n

valid approach to find the minimum for T (may be seen in (iii))                 (M1)

\n

graph of  T  OR  T'=0  OR  graph of T'

\n

x=177.472km

\n

x=177km                 A1

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

T=3.89980

\n

T=3.90 (hours)                 A1

\n


Note:
Only allow FT in (b)(ii) and (iii) for 0<x<215 and a function T that has a minimum in that interval.

\n

 

\n

[1 mark]

\n
b.iii.
\n
\n

C=200·215-x2+65242+150·x84                 (A1)

\n

valid approach to find the minimum for Cx  (may be seen in (ii))                 (M1)

\n

graph of C  OR  C'=0  OR  graph of C'

\n

x=188.706km

\n

x=189km                 A1

\n


Note:
Only allow FT from (b) if the function T has a minimum in 0<x<215.

\n

 

\n

[3 marks]

\n
c.i.
\n
\n

C=670.864

\n

C=$671                 A1

\n

 

\n

Note: Only allow FT from (c)(i) if the function C has a minimum in 0<x<215.

\n

 

\n

[1 mark]

\n
c.ii.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "21N.2.SL.TZ0.7", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

The sum of the first n terms of a geometric sequence is given by Sn=Σr=1n2378r.

\n
\n

Find the first term of the sequence, u1.

\n
[2]
\n
a.
\n
\n

Find S.

\n
[3]
\n
b.
\n
\n

Find the least value of n such that S-Sn<0.001.

\n
[4]
\n
c.
\n
", "Markscheme": "
\n

u1=S1=23×78                 (M1)

\n

=1424=712=0.583333                 A1

\n


[2 marks]

\n
a.
\n
\n

r=78=0.875                 (A1)

\n

substituting their values for u1 and r into S=u11-r                 (M1)

\n

=143=4.66666                 A1

\n


[3 marks]

\n
b.
\n
\n

attempt to substitute their values into the inequality or formula for Sn                 (M1)

\n

143-Σr=1n2378r<0.001  OR  Sn=7121-78n1-78

\n

attempt to solve their inequality using a table, graph or logarithms

\n

(must be exponential)                 (M1)

\n


Note: Award (M0) if the candidate attempts to solve S-un<0.001.

\n


correct critical value or at least one correct crossover value                 (A1)

\n

63.2675  OR  S-S63=0.001036  OR  S-S64=0.000906

\n

OR  S-S63-0.001=0.0000363683  OR  S-S64-0.001=0.0000931777

\n

least value is n=64                 A1

\n

 

\n

[4 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "21N.2.SL.TZ0.6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series" ] }, { "Question": "
\n

A function f is defined by fx=2x-1x+1, where x, x-1.

\n
\n

The graph of y=f(x) has a vertical asymptote and a horizontal asymptote.

\n
\n

Write down the equation of the vertical asymptote.

\n
[1]
\n
a.i.
\n
\n

Write down the equation of the horizontal asymptote.

\n
[1]
\n
a.ii.
\n
\n

On the set of axes below, sketch the graph of y=f(x).

\n

On your sketch, clearly indicate the asymptotes and the position of any points of intersection with the axes.

\n

\n
[3]
\n
b.
\n
\n

Hence, solve the inequality 0<2x-1x+1<2.

\n
[1]
\n
c.
\n
\n

Solve the inequality 0<2x-1x+1<2.

\n
[2]
\n
d.
\n
", "Markscheme": "
\n

x=-1          A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

y=2          A1

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

\n

rational function shape with two branches in opposite quadrants, with two correctly positioned asymptotes and asymptotic behaviour shown         A1

\n

axes intercepts clearly shown at x=12 and y=-1         A1A1

\n

 

\n

[3 marks]

\n
b.
\n
\n

x>12         A1

\n


Note:
Accept correct alternative correct notation, such as 12,  and ]12,[.

\n

 

\n

[1 mark]

\n
c.
\n
\n

EITHER

\n

attempts to sketch y=2x-1x+1        (M1)

\n


OR

\n

attempts to solve 2x-1=0        (M1)

\n

 

\n

Note: Award the (M1) if x=12 and x=-12 are identified.

\n

 

\n

THEN

\n

x<-12 or x>12         A1

\n

 

\n

Note: Accept the use of a comma. Condone the use of ‘and’. Accept correct alternative notation.

\n

  

\n

[2 marks]

\n
d.
\n
", "Examiners report": "
\n[N/A]\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "22M.1.AHL.TZ2.3", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-2-3-graphing", "ahl-2-16-graphing-modulus-equations-and-inequalities" ] }, { "Question": "
\n

Farmer Brown has built a new barn, on horizontal ground, on his farm. The barn has a cuboid base and a triangular prism roof, as shown in the diagram.

\n

\n

The cuboid has a width of 10 m, a length of 16 m and a height of 5 m.
The roof has two sloping faces and two vertical and identical sides, ADE and GLF.
The face DEFL slopes at an angle of 15° to the horizontal and ED = 7 m .

\n
\n

The roof was built using metal supports. Each support is made from five lengths of metal AE, ED, AD, EM and MN, and the design is shown in the following diagram.

\n

\n

ED = 7 m , AD = 10 m and angle ADE = 15° .
M is the midpoint of AD.
N is the point on ED such that MN is at right angles to ED.

\n
\n

Farmer Brown believes that N is the midpoint of ED.

\n
\n

Calculate the area of triangle EAD.

\n
[3]
\n
a.
\n
\n

Calculate the total volume of the barn.

\n
[3]
\n
b.
\n
\n

Calculate the length of MN.

\n
[2]
\n
c.
\n
\n

Calculate the length of AE.

\n
[3]
\n
d.
\n
\n

Show that Farmer Brown is incorrect.

\n
[3]
\n
e.
\n
\n

Calculate the total length of metal required for one support.

\n
[4]
\n
f.
\n
", "Markscheme": "
\n

* This question is from an exam for a previous syllabus, and may contain minor differences in marking or structure.

\n

(Area of EAD =)  1 2 × 10 × 7 × sin 15     (M1)(A1)

\n

Note: Award (M1) for substitution into area of a triangle formula, (A1) for correct substitution. Award (M0)(A0)(A0) if EAD or AED is considered to be a right-angled triangle.

\n

= 9.06 m2  (9.05866… m2)     (A1)   (G3)

\n

[3 marks]

\n
a.
\n
\n

(10 × 5 × 16) + (9.05866… × 16)     (M1)(M1)

\n

Note: Award (M1) for correct substitution into volume of a cuboid, (M1) for adding the correctly substituted volume of their triangular prism.

\n

= 945 m3  (944.938… m3)     (A1)(ft)  (G3)

\n

Note: Follow through from part (a).

\n

[3 marks]

\n
b.
\n
\n

MN 5 = sin 15      (M1)

\n

Note: Award (M1) for correct substitution into trigonometric equation.

\n

(MN =) 1.29(m) (1.29409… (m))     (A1) (G2)

\n

[2 marks]

\n
c.
\n
\n

(AE2 =) 102 + 72 − 2 × 10 × 7 × cos 15     (M1)(A1)

\n

Note: Award (M1) for substitution into cosine rule formula, and (A1) for correct substitution.

\n

(AE =) 3.71(m)  (3.71084… (m))     (A1) (G2)

\n

[3 marks]

\n
d.
\n
\n

ND2 = 52 − (1.29409…)2     (M1)

\n

Note: Award (M1) for correct substitution into Pythagoras theorem.

\n

(ND =) 4.83  (4.82962…)     (A1)(ft)

\n

Note: Follow through from part (c).

\n

OR

\n

1.29409 ND = tan 15      (M1)

\n

Note: Award (M1) for correct substitution into tangent.

\n

(ND =) 4.83  (4.82962…)     (A1)(ft)

\n

Note: Follow through from part (c).

\n

OR

\n

ND 5 = cos  15      (M1)

\n

Note: Award (M1) for correct substitution into cosine.

\n

(ND =) 4.83  (4.82962…)     (A1)(ft)

\n

Note: Follow through from part (c).

\n

OR

\n

ND2 = 1.29409…2 + 52 − 2 × 1.29409… × 5 × cos 75°     (M1)

\n

Note: Award (M1) for correct substitution into cosine rule.

\n

(ND =) 4.83  (4.82962…)     (A1)(ft)

\n

Note: Follow through from part (c).

\n

4.82962… ≠ 3.5   (ND ≠ 3.5)     (R1)(ft)

\n

OR

\n

4.82962… ≠ 2.17038…   (ND ≠ NE)     (R1)(ft)

\n

(hence Farmer Brown is incorrect)

\n

Note: Do not award (M0)(A0)(R1)(ft). Award (M0)(A0)(R0) for a correct conclusion without any working seen.

\n

[3 marks]

\n
e.
\n
\n

(EM2 =) 1.29409…2 + (7 − 4.82962…)2     (M1)

\n

Note: Award (M1) for their correct substitution into Pythagoras theorem.

\n

OR

\n

(EM2 =) 52 + 72 − 2 × 5 × 7 × cos 15     (M1)

\n

Note: Award (M1) for correct substitution into cosine rule formula.

\n

(EM =) 2.53(m) (2.52689...(m))     (A1)(ft) (G2)(ft)

\n

Note: Follow through from parts (c), (d) and (e).

\n

(Total length =) 2.52689… + 3.71084… + 1.29409… +10 + 7     (M1)

\n

Note: Award (M1) for adding their EM, their parts (c) and (d), and 10 and 7.

\n

= 24.5 (m)    (24.5318… (m))     (A1)(ft) (G4)

\n

Note: Follow through from parts (c) and (d).

\n

[4 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "18M.2.SL.TZ1.T_1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

The height of water, in metres, in Dungeness harbour is modelled by the function H(t)=asin(b(t-c))+d, where t is the number of hours after midnight, and a, b, c and d are constants, where a>0, b>0 and c>0.

\n

The following graph shows the height of the water for 13 hours, starting at midnight.

\n

\n

The first high tide occurs at 04:30 and the next high tide occurs 12 hours later. Throughout the day, the height of the water fluctuates between 2.2m and 6.8m.

\n

All heights are given correct to one decimal place.

\n
\n

Show that b=π6.

\n
[1]
\n
a.
\n
\n

Find the value of a.

\n
[2]
\n
b.
\n
\n

Find the value of d.

\n
[2]
\n
c.
\n
\n

Find the smallest possible value of c.

\n
[3]
\n
d.
\n
\n

Find the height of the water at 12:00.

\n
[2]
\n
e.
\n
\n

Determine the number of hours, over a 24-hour period, for which the tide is higher than 5 metres.

\n
[3]
\n
f.
\n
", "Markscheme": "
\n

12=2πb  OR  b=2π12                A1

\n

b=π6                AG

\n

 

\n

[1 mark]

\n
a.
\n
\n

a=6.8-2.22  OR  a=max-min2                (M1)

\n

=2.3m                A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

d=6.8+2.22  OR  d=max+min2                (M1)

\n

=4.5m                A1

\n

 

\n

[2 marks]

\n
c.
\n
\n

METHOD 1

\n

substituting t=4.5 and H=6.8 for example into their equation for H                (A1)

\n

6.8=2.3sinπ64.5-c+4.5

\n

attempt to solve their equation                (M1)

\n

c=1.5                A1

\n

 

\n

METHOD 2

\n

using horizontal translation of 124                (M1)

\n

4.5-c=3                (A1)

\n

c=1.5                A1

\n

 

\n

METHOD 3

\n

H't=2.3π6cosπ6t-c                (A1)

\n

attempts to solve their H'4.5=0 for c                (M1)

\n

2.3π6cosπ64.5-c=0

\n

c=1.5                A1

\n

 

\n

[3 marks]

\n
d.
\n
\n

attempt to find H when t=12 or t=0, graphically or algebraically                (M1)

\n

H=2.87365

\n

H=2.87m                A1

\n

 

\n

[2 marks]

\n
e.
\n
\n

attempt to solve 5=2.3sinπ6t-1.5+4.5                (M1)

\n

times are t=1.91852 and t=7.08147 , t=13.9185, t=19.0814                (A1)

\n

total time is 2×7.081-1.919

\n

10.3258

\n

=10.3 (hours)                A1

\n


Note: Accept 10.

\n

 

\n

[3 marks]

\n
f.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "21N.2.SL.TZ0.8", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology" ] }, { "Question": "
\n

A function f is defined by fx=x1-x2 where -1x1.

\n

The graph of y=f(x) is shown below.

\n

\n
\n

Show that f is an odd function.

\n
[2]
\n
a.
\n
\n

The range of f is ayb, where a, b.

\n

Find the value of a and the value of b.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

attempts to replace x with -x        M1

\n

f-x=-x1--x2

\n

=-x1--x2=-fx         A1

\n

 

\n

Note: Award M1A1 for an attempt to calculate both f-x and -f-x independently, showing that they are equal.
Note: Award M1A0 for a graphical approach including evidence that either the graph is invariant after rotation by 180° about the origin or the graph is invariant after a reflection in the y-axis and then in the x-axis (or vice versa).

\n

 

\n

so f is an odd function         AG

\n

  

\n

[2 marks]

\n
a.
\n
\n

attempts both product rule and chain rule differentiation to find f'x        M1

\n

f'x=x×12×-2x×1-x2-12+1-x212×1 =1-x2-x21-x2         A1

\n

=1-2x21-x2

\n

sets their f'x=0        M1

\n

x=±12         A1

\n

attempts to find at least one of f±12         (M1)

\n

 

\n

Note: Award M1 for an attempt to evaluate fx at least at one of their f'x=0  roots.

\n

 

\n

a=-12  and b=12         A1

\n

 

\n

Note: Award A1 for -12y12.

\n

  

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.AHL.TZ2.6", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-14-odd-and-even-functions-self-inverse-inverse-and-domain-restriction", "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection" ] }, { "Question": "
\n

Prove by contradiction that the equation 2x3+6x+1=0 has no integer roots.

\n
", "Markscheme": "
\n

METHOD 1 (rearranging the equation)

\n

assume there exists some α such that 2α3+6α+1=0         M1

\n


Note:
Award M1 for equivalent statements such as ‘assume that α is an integer root of 2α3+6α+1=0’. Condone the use of x throughout the proof.

\n

Award M1 for an assumption involving α3+3α+12=0.

\n

Note: Award M0 for statements such as “let’s consider the equation has integer roots…” ,“let α be a root of 2α3+6α+1=0…”

\n

Note: Subsequent marks after this M1 are independent of this M1 and can be awarded.

\n

 

\n

attempts to rearrange their equation into a suitable form         M1

\n


EITHER

\n

2α3+6α=-1          A1

\n

α2α3+6α is even          R1

\n

2α3+6α=-1 which is not even and so α cannot be an integer          R1

\n


Note:
Accept ‘2α3+6α=-1 which gives a contradiction’.

\n


OR

\n

1=2-α3-3α          A1

\n

α-α3-3α          R1

\n

1 is even which is not true and so α cannot be an integer          R1

\n


Note:
Accept ‘1 is even which gives a contradiction’.

\n


OR

\n

12=-α3-3α          A1

\n

α-α3-3α          R1

\n

-α3-3α is is not an integer =12 and so α cannot be an integer          R1

\n


Note:
Accept ‘ -α3-3α is not an integer =12 which gives a contradiction’.

\n


OR

\n

α=-12α2+3          A1

\n

α-12α2+3          R1

\n

-12α2+3 is not an integer and so α cannot be an integer          R1

\n


Note:
Accept -12α2+3 is not an integer which gives a contradiction’.

\n


THEN

\n

so the equation 2x3+6x+1=0 has no integer roots           AG

\n

 

\n

METHOD 2

\n

assume there exists some α such that 2α3+6α+1=0         M1

\n


Note:
 Award M1 for equivalent statements such as ‘assume that α is an integer root of 2α3+6α+1=0’. Condone the use of x throughout the proof. Award M1 for an assumption involving α3+3α+12=0 and award subsequent marks based on this.

\n

Note: Award M0 for statements such as “let’s consider the equation has integer roots…” ,“let α be a root of 2α3+6α+1=0…”

\n

Note: Subsequent marks after this M1 are independent of this M1 and can be awarded.

\n

 

\n

let fx=2x3+6x+1  (and fα=0)

\n

f'x=6x2+6>0 for all x f is a (strictly) increasing function         M1A1

\n

f0=1 and f-1=-7          R1

\n

thus fx=0 has only one real root between -1 and 0, which gives a contradiction

\n

(or therefore, contradicting the assumption that fα=0 for some α),          R1

\n

so the equation 2x3+6x+1=0 has no integer roots           AG

\n

  

\n

[5 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "22M.1.AHL.TZ2.9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

A function f is defined by fx=1x2-2x-3, where x, x-1, x3.

\n
\n

A function g is defined by gx=1x2-2x-3, where x, x>3.

\n
\n

The inverse of g is g-1.

\n
\n

A function h is defined by hx=arctanx2, where x.

\n
\n

Sketch the curve y=f(x), clearly indicating any asymptotes with their equations. State the coordinates of any local maximum or minimum points and any points of intersection with the coordinate axes.

\n
[6]
\n
a.
\n
\n

Show that g-1x=1+4x2+xx.

\n
[6]
\n
b.i.
\n
\n

State the domain of g-1.

\n
[1]
\n
b.ii.
\n
\n

Given that hga=π4, find the value of a.

\n

Give your answer in the form p+q2r, where p, q, r+.

\n
[7]
\n
c.
\n
", "Markscheme": "
\n

\n

 

\n

y-intercept 0,-13         A1

\n


Note:
Accept an indication of -13 on the y-axis.

\n


vertical asymptotes x=-1 and x=3          A1

\n

horizontal asymptote y=0          A1

\n

uses a valid method to find the x-coordinate of the local maximum point          (M1)

\n


Note:
For example, uses the axis of symmetry or attempts to solve f'x=0.

\n


local maximum point 1,-14          A1

\n


Note:
Award (M1)A0 for a local maximum point at x=1 and coordinates not given.

\n


three correct branches with correct asymptotic behaviour and the key features in approximately correct relative positions to each other          A1

\n

 

\n

[6 marks]

\n
a.
\n
\n

x=1y2-2y-3           M1

\n


Note: Award M1 for interchanging x and y (this can be done at a later stage).

\n

 

\n

EITHER

\n

attempts to complete the square           M1

\n

y2-2y-3=y-12-4          A1

\n

x=1y-12-4

\n

y-12-4=1xy-12=4+1x          A1

\n

y-1=±4+1x =±4x+1x

\n

 

\n

OR

\n

attempts to solve xy2-2xy-3x-1=0 for y         M1

\n

y=--2x±-2x2+4x3x+12x         A1

\n


Note:
Award A1 even if - (in ±) is missing

\n


=2x±16x2+4x2x         A1

\n

 

\n

THEN

\n

=1±4x2+xx         A1

\n

y>3 and hence y=1-4x2+xx is rejected                R1 

\n

 

\n

Note: Award R1 for concluding that the expression for y must have the ‘+’ sign.
The R1 may be awarded earlier for using the condition x>3.

\n

 

\n

y=1+4x2+xx

\n

g-1x=1+4x2+xx         AG

\n

 

\n

[6 marks]

\n
b.i.
\n
\n

domain of g-1 is x>0         A1

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

attempts to find hga          (M1)

\n

hga=arctanga2   hga=arctan12a2-2a-3          (A1)

\n

arctanga2=π4   arctan12a2-2a-3=π4

\n

attempts to solve for ga         M1

\n

ga=2  1a2-2a-3=2

\n

 

\n

EITHER

\n

a=g-12         A1

\n

attempts to find their g-12         M1

\n

a=1+422+22         A1

\n

 

\n

Note: Award all available marks to this stage if x is used instead of a.

\n


OR

\n

2a2-4a-7=0         A1

\n

attempts to solve their quadratic equation         M1

\n

a=--4±-42+4274  =4±724         A1

\n


Note: Award all available marks to this stage if x is used instead of a.

\n


THEN

\n

a=1+322  (as a>3)         A1

\n

p=1, q=3, r=2

\n

 

\n

Note: Award A1 for a=1+1218  p=1, q=1, r=18

\n

 

\n

[7 marks]

\n
c.
\n
", "Examiners report": "
\n

Part (a) was generally well done. It was pleasing to see how often candidates presented complete sketches here. Several decided to sketch using the reciprocal function. Occasionally, candidates omitted the upper branches or forgot to calculate the y-coordinate of the maximum.

\n

Part (b): The majority of candidates knew how to start finding the inverse, and those who attempted completing the square or using the quadratic formula to solve for y made good progress (both methods equally seen). Otherwise, they got lost in the algebra. Very few explicitly justified the rejection of the negative root.

\n

Part (c) was well done in general, with some algebraic errors seen in occasions.

\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.1.AHL.TZ2.11", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection", "ahl-2-14-odd-and-even-functions-self-inverse-inverse-and-domain-restriction", "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

By using the substitution u=secx or otherwise, find an expression for 0π3secnxtanxdx in terms of n, where n is a non-zero real number.

\n
", "Markscheme": "
\n

METHOD 1

\n

u=secxdu=secxtanxdx         (A1)

\n

attempts to express the integral in terms of u         M1

\n

12un-1du         A1

\n

=1nun12  (=1nsecnx0π3)          A1

\n

 

\n

Note: Condone the absence of or incorrect limits up to this point.

\n

 

\n

=2n-1nn         M1

\n

=2n-1n          A1

\n

 

\n

Note: Award M1 for correct substitution of their limits for u into their antiderivative for u (or given limits for x into their antiderivative for x).

\n

 

\n

METHOD 2

\n

secnxtanxdx=secn-1xsecxtanxdx         (A1)

\n

applies integration by inspection         (M1)

\n

=1nsecnx0π3          A2

\n

 

\n

Note: Award A2 if the limits are not stated.

\n

 

\n

=1nsecnπ3-secn0         M1

\n

 

\n

Note: Award M1 for correct substitution into their antiderivative.

\n

 

\n

=2n-1n          A1

\n

  

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "22M.1.AHL.TZ2.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule" ] }, { "Question": "
\n

A continuous random variable X has the probability density function

\n

fx=2b-ac-ax-a,axc2b-ab-cb-x,c<xb0,otherwise.

\n

The following diagram shows the graph of y=fx for axb.

\n

\n

Given that ca+b2, find an expression for the median of X in terms of a, b and c.

\n
", "Markscheme": "
\n

let m be the median

\n


EITHER

\n

attempts to find the area of the required triangle          M1

\n

base is m-a          (A1)

\n

and height is 2b-ac-am-a

\n

area =12m-a×2b-ac-am-a  =m-a2b-ac-a         A1

\n

 

\n

OR

\n

attempts to integrate the correct function          M1

\n

am2b-ac-ax-adx

\n

=2b-ac-a12x-a2am  OR  2b-ac-ax22-axam         A1A1

\n

 

\n

Note: Award A1 for correct integration and A1 for correct limits.

\n

 

\n

THEN

\n

sets up (their) am2b-ac-ax-adx or area =12         M1

\n

 

\n

Note: Award M0A0A0M1A0A0 if candidates conclude that m>c and set up their area or sum of integrals =12.

\n

 

\n

m-a2b-ac-a=12

\n

m=a±b-ac-a2         (A1)

\n

 

\n

as m>a, rejects m=a-b-ac-a2

\n

so m=a+b-ac-a2         A1

\n

  

\n

[6 marks]

\n
", "Examiners report": "
\n[N/A]\n
", "question_id": "22M.1.AHL.TZ2.8", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

In the following Argand diagram, the points Z1, O and Z2 are the vertices of triangle Z1OZ2 described anticlockwise.

\n

\n

The point Z1 represents the complex number z1=r1eiα, where r1>0. The point Z2 represents the complex number z2=r2eiθ, where r2>0.

\n

Angles α, θ are measured anticlockwise from the positive direction of the real axis such that 0α, θ<2π and 0<α-θ<π.

\n
\n

In parts (c), (d) and (e), consider the case where Z1OZ2 is an equilateral triangle.

\n
\n

Let z1 and z2 be the distinct roots of the equation z2+az+b=0 where z and a, b.

\n
\n

Show that z1z2=r1r2eiα-θ where z2 is the complex conjugate of z2.

\n
[2]
\n
a.
\n
\n

Given that Rez1z2=0, show that Z1OZ2 is a right-angled triangle.

\n
[2]
\n
b.
\n
\n

Express z1 in terms of z2.

\n
[2]
\n
c.i.
\n
\n

Hence show that z12+z22=z1z2.

\n
[4]
\n
c.ii.
\n
\n

Use the result from part (c)(ii) to show that a2-3b=0.

\n
[5]
\n
d.
\n
\n

Consider the equation z2+az+12=0, where z and a.

\n

Given that 0<α-θ<π, deduce that only one equilateral triangle Z1OZ2 can be formed from the point O and the roots of this equation.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

z2=r2e-iθ          (A1)

\n

z1z2=r1eiαr2e-iθ           A1

\n

z1z2=r1r2eiα-θ           AG

\n


Note: Accept working in modulus-argument form

\n

 

\n

[2 marks]

\n
a.
\n
\n

Rez1z2=r1r2cosα-θ  =0           A1

\n

α-θ=arcos0  r1,r2>0

\n

α-θ=π2  (as 0<α-θ<π)           A1

\n

so Z1OZ2 is a right-angled triangle           AG

\n

 

\n

[2 marks]

\n
b.
\n
\n

EITHER

\n

z1z2=r1r2eiα-θ=eiπ3  (since r1=r2)            (M1)

\n


OR

\n

z1=r2eiθ+π3  =r2eiθeiπ3            (M1)

\n


THEN

\n

z1=z2eiπ3           A1

\n

 

\n

Note: Accept working in either modulus-argument form to obtain z1=z2cosπ3+isinπ3 or in Cartesian form to obtain z1=z212+32i.

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

substitutes z1=z2eiπ3 into z12+z22             M1

\n

z12+z22=z22ei2π3+z22  =z22ei2π3+1             A1

\n

 

\n

EITHER

\n

ei2π3+1=eiπ3             A1

\n


OR

\n

z22ei2π3+1=z22-12+32i+1

\n

=z2212+32i             A1

\n

 

\n

THEN

\n

z12+z22=z22eiπ3

\n

=z2z2eiπ3  and  z2eiπ3=z1             A1

\n

so z12+z22=z1z2             AG

\n

 

\n

Note: For candidates who work on the LHS and RHS separately to show equality, award M1A1 for z12+z22=z22ei2π3+z22  =z22ei2π3+1, A1 for z1z2=z22eiπ3 and A1 for ei2π3+1=eiπ3. Accept working in either modulus-argument form or in Cartesian form.

\n

 

\n

[4 marks]

\n
c.ii.
\n
\n

METHOD 1

\n

z1+z2=-a  and  z1z2=b              (A1)

\n

a2=z12+z22+2z1z2             A1

\n

a2=2z1z2+z1z2=3z1z2             A1

\n

substitutes b=z1z2 into their expression             M1

\n

a2=2b+b  OR  a2=3b             A1

\n


Note: If z1+z2=-a is not clearly recognized, award maximum (A0)A1A1M1A0.

\n

 

\n

so a2-3b=0              AG

\n

 

\n

METHOD 2

\n

z1+z2=-a  and  z1z2=b              (A1)

\n

z1+z22=z12+z22+2z1z2             A1

\n

z1+z22=2z1z2+z1z2=3z1z2             A1

\n

substitutes b=z1z2 and z1+z2=-a into their expression              M1

\n

a2=2b+b  OR  a2=3b             A1

\n


Note: If z1+z2=-a is not clearly recognized, award maximum (A0)A1A1M1A0.

\n


so a2-3b=0              AG

\n

 

\n

[5 marks]

\n
d.
\n
\n

a2-3×12=0

\n

a=±6  z2±6z+12=0             A1

\n

for a=-6:

\n

z1=3+3i, z2=3-3i  and  α-θ=-5π3  which does not satisfy 0<α-θ<π             R1

\n

for a=6:

\n

z1=-3-3i, z2=-3+3i  and  α-θ=π3             A1

\n

so (for 0<α-θ<π), only one equilateral triangle can be formed from point O and the two roots of this equation             AG

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n

The vast majority of candidates scored full marks in parts (a) and (b). If they did not, it was normally due to the lack of rigour in setting out of the answer to a \"show that\" question. Part (c) was, though, more often than not poorly done. Many candidates could not use the given condition (equilateral triangle) to find z1 in terms of z2. Part (d) was well answered by a rather high number of candidates.

\n

Only a handful of students made good progress in (e), not even finding the possible values for a.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "22M.1.AHL.TZ2.12", "topics": [ "topic-1-number-and-algebra", "topic-2-functions" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag", "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

In this question, give all answers correct to two decimal places.

\n

Sam invests $1700 in a savings account that pays a nominal annual rate of interest of 2.74%, compounded half-yearly. Sam makes no further payments to, or withdrawals from, this account.

\n
\n

David also invests $1700 in a savings account that pays an annual rate of interest of r%, compounded yearly. David makes no further payments or withdrawals from this account.

\n
\n

Find the amount that Sam will have in his account after 10 years.

\n
[3]
\n
a.
\n
\n

Find the value of r required so that the amount in David’s account after 10 years will be equal to the amount in Sam’s account.

\n
[2]
\n
b.
\n
\n

Find the interest David will earn over the 10 years.

\n
[1]
\n
c.
\n
", "Markscheme": "
\n

Note: The first time an answer is not given to two decimal places, the final A1 in that part is not awarded.

\n

 

\n

EITHER

\n

N=10              OR             N=20

\n

I%=2.74                           I%=2.74

\n

PV=1700                     PV=1700

\n

P/Y=1                              P/Y=2

\n

C/Y=2                              C/Y=2              (M1)(A1)

\n

 

\n

Note: Award (M1) for an attempt to use a financial app in their technology with at least two entries seen, and award (A1) for all entries correct. Accept a positive or negative value for PV.

\n


OR

\n

17001+0.027422×10         (M1)(A1)

\n

 

\n

Note: Award (M1) for substitution into compound interest formula.
Award (A1) for correct substitution.

\n


THEN

\n

$2231.71        A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

Note: The first time an answer is not given to two decimal places, the final A1 in that part is not awarded.

\n

 

\n

EITHER

\n

N=10

\n

PV=1700

\n

FV=±2231.71

\n

P/Y=1

\n

C/Y=1             (M1)

\n

 

\n

Note: Award (M1) for an attempt to use a financial app in their technology with at least two entries seen.

\n


OR

\n

17001+r10010=2231.71         (M1)

\n

 

\n

THEN

\n

r=2.75876

\n

r=2.76        A1

\n

 

\n

Note: Ignore omission of opposite signs for PV and FV if r=2.76 is obtained.

\n

 

\n

[2 marks]

\n
b.
\n
\n

Note: The first time an answer is not given to two decimal places, the final A1 in that part is not awarded.

\n

 

\n

$531.71         A1 

\n

 

\n

[1 mark]

\n
c.
\n
", "Examiners report": "
\n

This was the only short question which was not common to both HL and SL papers.

\n

Candidates found this question a straightforward start, with the majority being able to attempt all three parts. While most candidates initially gave answers to two decimal places as required, many subsequently rounded their answers to three significant figures. In parts (a) and (b), most used the compound interest formula rather than the finance app on their GDC. Difficulty using the formula arose in determining the value of r (0.0274 was often seen, rather than 2.74) and the value of k. Many candidates struggled to correctly interpret 'half-yearly', and attempted to use either k=6 or k=12 in the formula.

\n

In part (b), a correct equation was usually seen, but lengthy analytical methods to solving it were favoured, with varying degrees of success, over an approach using the GDC. A common error was an attempt to use logarithms rather than the tenth root. It was not uncommon to see a final answer of either 2.76% or 0.0276, rather than 2.76. Many did not know what was meant by 'interest' in part (c). Those that did often recalculated David's amount using their value of r, rather than subtract $1700 from Sam's amount.

\n

The candidates who attempted to use a finance app on their GDC in this question were generally able to give accurate and concise answers. In the case where they obtained an incorrect answer, most gave sufficient detail of the values they were using in the app, to be awarded the method mark. The most common error seen was the use of an incorrect value for the number of payments per year or the number of compounding periods per year.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.2.SL.TZ1.1", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-4-financial-apps-compound-int-annual-depreciation" ] }, { "Question": "
\n

The number of hours spent exercising each week by a group of students is shown in the following table.

\n

\n

The median is 4.5 hours.

\n
\n

Find the value of x.

\n
[2]
\n
a.
\n
\n

Find the standard deviation.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

EITHER

\n

recognising that half the total frequency is 10 (may be seen in an ordered list or indicated on the frequency table)          (A1)

\n


OR

\n

5+1+4=3+x         (A1)

\n


OR

\n

f=20         (A1)

\n


THEN

\n

x=7        A1 

\n

  

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

1.58429

\n

1.58        A2

\n

 

\n

METHOD 2

\n

EITHER

\n

σ2=5×2-4.32+1×3-4.32+4×4-4.32+3×5-4.32+7×6-4.3220  =2.51         (A1)

\n


OR

\n

σ2=5×22+1×32+4×42+3×52+7×6220-4.32  =2.51         (A1)

\n


THEN

\n

σ=2.51=1.58429

\n

=1.58        A1 

\n

  

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n

Most candidates attempted both parts, with varying levels of success, particularly in part (b). 

\n

In part (a), the most successful approach seen was from candidates who made an ordered list to visualize the given data set, which enabled them to recognise either the number of sixes required for the median to lie at 4.5, or the total frequency. The most common error was to mistake the median for the mean, which led to a non-integer value of x=9.67.

\n

Part (b) proved to be more challenging, with many candidates either not taking into account the frequency of the exercise time when generating the summary statistics or treating frequency as an additional variable and using two-variable statistics on their GDC. With both, this led to σ=1.41 being the most common wrong answer seen. A few candidates gave the sample standard deviation rather than the population standard deviation. A number of candidates attempted to use the standard deviation formula but were usually not successful. This formula is not in the course, although it can be obtained in the HL section of the formula booklet.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.SL.TZ1.2", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

A company is designing a new logo. The logo is created by removing two equal segments from a rectangle, as shown in the following diagram.

\n

\n

The rectangle measures 5cm by 4cm. The points A and B lie on a circle, with centre O and radius 2cm, such that AÔB=θ, where 0<θ<π. This information is shown in the following diagram.

\n

\n
\n

Find the area of one of the shaded segments in terms of θ.

\n
[3]
\n
a.
\n
\n

Given that the area of the logo is 13.4cm2, find the value of θ.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

valid approach to find area of segment by finding area of sector – area of triangle           (M1)

\n

12r2θ-12r2sinθ

\n

1222θ-1222sinθ           (A1)

\n

area =2θ-2sinθ          A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

EITHER

\n

area of logo = area of rectangle – area of segments           (M1)

\n

5×4-2×2θ-2sinθ=13.4           (A1)

\n


OR

\n

area of one segment =20-13.42 =3.3           (M1)

\n

2θ-2sinθ=3.3           (A1)

\n


THEN

\n

θ=2.35672

\n

θ=2.36 (do not accept an answer in degrees)          A1

\n

 

\n

Note: Award (M1)(A1)A0 if there is more than one solution.
Award (M1)(A1FT)A0 if the candidate works in degrees and obtains a final answer of 135.030

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n

The first part of this question proved particularly challenging for many candidates. Most were able to obtain the area of the sector, but then did not recognise that the segment was formed by subtracting the area of the triangle. Those that did, often struggled to find the appropriate triangle area formula to do so. 

\n

The second part of the question was generally answered more successfully, although sometimes only one of the segments was subtracted from the whole rectangle. Many candidates who had a correct equation lacked the requisite calculator skills to obtain a solution. Those that had an incorrect expression for the area from part (a), often obtained 20-4θ=13.4. This was a significantly easier equation to solve, and consequently these candidates were not awarded the final A mark for a final answer of θ=1.65.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.SL.TZ1.3", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-4-circle-radians-arcs-sectors" ] }, { "Question": "
\n

A discrete random variable, X, has the following probability distribution:

\n

\n
\n

Show that 2k2-k+0.12=0.

\n
[1]
\n
a.
\n
\n

Find the value of k, giving a reason for your answer.

\n
[3]
\n
b.
\n
\n

Hence, find E(X).

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

0.41+k-0.28+0.46+0.29-2k2=1  OR  k-2k2+0.01=0.13 (or equivalent)          A1

\n

2k2-k+0.12=0          AG

\n

 

\n

[1 mark]

\n
a.
\n
\n

one of 0.2 OR 0.3           (M1)

\n

k=0.3           A1

\n

reasoning to reject k=0.2  eg  P1=k-0.280 therefore k0.2          R1

\n

 

\n

[3 marks]

\n
b.
\n
\n

attempting to use the expected value formula          (M1)

\n

E(X)=0×0.41+1×0.3-0.28+2×0.46+3×0.29-2×0.32

\n

=1.27           A1

\n


Note: Award M1A0 if additional values are given.

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n

Part (a) was well done in this question, with most candidates recognising that the probabilities needed to sum to 1. Many candidates also approached part (b) appropriately. While many did so by graphing the quadratic on the GDC and identifying the zeros, most solved the equation analytically. Those that used the GDC, often assumed there was only one x-intercept and did not investigate the relevant area of the graph in more detail. While some who found the two required values of k recognised that k = 0.2 should be rejected by referring to the original probabilities, most had lost sight of the context of the question, and were unable to give a valid reason using P(X = 1) to reject this solution. Those that obtained one solution in part (b), were generally able to find the expected value successfully in part (c).

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.2.SL.TZ1.4", "topics": [ "topic-4-statistics-and-probability", "topic-2-functions" ], "subtopics": [ "sl-4-7-discrete-random-variables", "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

A particle moves along a straight line so that its velocity, vm s-1, after t seconds is given by vt=esint+4sint for 0t6.

\n
\n

Find the value of t when the particle is at rest.

\n
[2]
\n
a.
\n
\n

Find the acceleration of the particle when it changes direction.

\n
[3]
\n
b.
\n
\n

Find the total distance travelled by the particle.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

recognizing at rest v=0          (M1)

\n

t=3.34692

\n

t=3.35 (seconds)           A1

\n

 

\n

Note: Award (M1)A0 for additional solutions to v=0 eg t=-0.205 or t=6.08.

\n

 

\n

[2 marks]

\n
a.
\n
\n

recognizing particle changes direction when v=0 OR when t=3.34692          (M1)

\n

a=-4.71439

\n

a=-4.71ms-2           A2

\n

 

\n

[3 marks]

\n
b.
\n
\n

distance travelled =06vdt  OR

\n

03.34esint+4sintdt-3.346esint+4sintdt  =14.3104+6.44300          (A1)

\n

=20.7534

\n

=20.8 (metres)           A1

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n

The majority of candidates found this question challenging but were often able to gain some of the marks in each part. However, it was not uncommon to see candidates manage either all of this question, or none of it, which unfortunately suggested that not all candidates had covered this content.

\n

In part (a), while many recognized v=0 when the particle is at rest, a common error was to assume that t=0. It was pleasing to see the majority of those who had the correct equation, manage to progress to the correct value of t, having recognised the domain and the angle measure. Inevitably, a few candidates ignored the domain and obtained t=-0.205, or found t=0.

\n

Part (b) was not well done. The most successful approach was to use the GDC to find the gradient of the curve at the value of t obtained in part (a). This was well communicated, concise and generally accurate, although some either rounded incorrectly, or obtained a=4.71 rather than a=-4.71. Of those that did not use the GDC, many were aware that a(t)=v'(t) and made an attempt to find an expression for v'(t). However, the majority appeared not to recognise when the particle would change direction and went on to substitute an incorrect value of t, not realising that they had obtained the required value earlier.

\n

Those that had been successful in parts (a) and (b), particularly if they had been using their GDC, were generally able to complete part (c). However, it was disappointing that many candidates who understood that an integral was required, did not refer to the formula booklet and omitted the absolute value from the integrand.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.2.SL.TZ1.5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

Let A and B be two independent events such that P(AB')=0.16 and P(AB)=0.36.

\n
\n

Given that P(AB)=x, find the value of x.

\n
[4]
\n
a.
\n
\n

Find PA'B'.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

EITHER

\n

one of PA=x+0.16  OR  PB=x+0.36           A1

\n


OR

\n

           A1

\n

 

\n

THEN

\n

attempt to equate their P(AB) with their expression for PA×PB           M1

\n

P(AB)=PA×PBx=x+0.16×x+0.36           A1

\n

x=0.24           A1

\n

 

\n

METHOD 2

\n

attempt to form at least one equation in PA and PB using independence           M1

\n

PAB'=PA×PB' PA×1-PB=0.16  OR

\n

PA'B=PA'×PB 1-PA×PB=0.36

\n

PA=0.4 and PB=0.6           A1

\n

P(AB)=PA×PB=0.4×0.6            (A1)

\n

x=0.24           A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

METHOD 1

\n

recognising PA'B'=PA'            (M1)

\n

=1-0.16-0.24

\n

=0.6           A1

\n

 

\n

METHOD 2

\n

PB=0.36+0.24=0.6

\n

PA'B'=PA'B'PB'  =0.240.4            (A1)

\n

=0.6           A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.SL.TZ1.6", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

This question asks you to explore properties of a family of curves of the type y2=x3+ax+b for various values of a and b, where a, b.

\n
\n

On the same set of axes, sketch the following curves for -2x2 and -2y2, clearly indicating any points of intersection with the coordinate axes.

\n
\n

Now, consider curves of the form y2=x3+b, for x-b3, where b+.

\n
\n

Next, consider the curve y2=x3+x, x0.

\n
\n

The curve y2=x3+x has two points of inflexion. Due to the symmetry of the curve these points have the same x-coordinate.

\n
\n

P(x, y) is defined to be a rational point on a curve if x and y are rational numbers.

\n

The tangent to the curve y2=x3+ax+b at a rational point P intersects the curve at another rational point Q.

\n

Let C be the curve y2=x3+2, for x-23. The rational point P(-1, -1) lies on C.

\n
\n

y2=x3, x0

\n
[2]
\n
a.i.
\n
\n

y2=x3+1, x-1

\n
[2]
\n
a.ii.
\n
\n

Write down the coordinates of the two points of inflexion on the curve y2=x3+1.

\n
[1]
\n
b.i.
\n
\n

By considering each curve from part (a), identify two key features that would distinguish one curve from the other.

\n
[1]
\n
b.ii.
\n
\n

By varying the value of b, suggest two key features common to these curves.

\n
[2]
\n
c.
\n
\n

Show that dydx=±3x2+12x3+x, for x>0.

\n
[3]
\n
d.i.
\n
\n

Hence deduce that the curve y2=x3+x has no local minimum or maximum points.

\n
[1]
\n
d.ii.
\n
\n

Find the value of this x-coordinate, giving your answer in the form x=p3+qr, where p, q, r.

\n
[7]
\n
e.
\n
\n

Find the equation of the tangent to C at P.

\n
[2]
\n
f.i.
\n
\n

Hence, find the coordinates of the rational point Q where this tangent intersects C, expressing each coordinate as a fraction.

\n
[2]
\n
f.ii.
\n
\n

The point S(-1 , 1) also lies on C. The line [QS] intersects C at a further point. Determine the coordinates of this point.

\n
[5]
\n
g.
\n
", "Markscheme": "
\n

\n

approximately symmetric about the x-axis graph of y2=x3         A1

\n

including cusp/sharp point at (0, 0)         A1

\n

 

\n

[2 marks]

\n

 

\n

Note: Final A1 can be awarded if intersections are in approximate correct place with respect to the axes shown. Award A1A1A1A0 if graphs ‘merge’ or ‘cross’ or are discontinuous at x-axis but are otherwise correct. Award A1A0A0A0 if only one correct branch of both curves are seen.

\n

Note: If they sketch graphs on separate axes, award a maximum of 2 marks for the ‘best’ response seen. This is likely to be A1A1A0A0.

\n
a.i.
\n
\n

approximately symmetric about the x-axis graph of y2=x3+1 with approximately correct gradient at axes intercepts        A1
some indication of position of intersections at x=1, y=±1         A1

\n

[2 marks]

\n

 

\n

Note: Final A1 can be awarded if intersections are in approximate correct place with respect to the axes shown. Award A1A1A1A0 if graphs ‘merge’ or ‘cross’ or are discontinuous at x-axis but are otherwise correct. Award A1A0A0A0 if only one correct branch of both curves are seen.

\n

Note: If they sketch graphs on separate axes, award a maximum of 2 marks for the ‘best’ response seen. This is likely to be A1A1A0A0.

\n
a.ii.
\n
\n

0, 1 and 0, -1       A1

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

Any two from:

\n

y2=x3 has a cusp/sharp point, (the other does not)

\n

graphs have different domains

\n

y2=x3+1 has points of inflexion, (the other does not)

\n

graphs have different x-axis intercepts (one goes through the origin, and the other does not)

\n

graphs have different y-axis intercepts      A1

\n

 

\n

Note: Follow through from their sketch in part (a)(i). In accordance with marking rules, mark their first two responses and ignore any subsequent.

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

Any two from:

\n

as , x, y±

\n

as x, y2=x3+b is approximated by y2=x3 (or similar)

\n

they have x intercepts at x=-b3

\n

they have y intercepts at y=±b

\n

they all have the same range

\n

y=0 (or x-axis) is a line of symmetry

\n

they all have the same line of symmetry y=0

\n

they have one x-axis intercept

\n

they have two y-axis intercepts

\n

they have two points of inflexion

\n

at x-axis intercepts, curve is vertical/infinite gradient

\n

there is no cusp/sharp point at x-axis intercepts     A1A1

\n

 

\n

Note: The last example is the only valid answer for things “not” present. Do not credit an answer of “they are all symmetrical” without some reference to the line of symmetry.

\n

Note: Do not allow same/ similar shape or equivalent.

\n

Note: In accordance with marking rules, mark their first two responses and ignore any subsequent.

\n

 

\n

[2 marks]

\n
c.
\n
\n

METHOD 1

\n

attempt to differentiate implicitly         M1

\n

2ydydx=3x2+1         A1

\n

dydx=3x2+12y  OR  ±2x3+xdydx=3x2+1         A1

\n

dydx=±3x2+12x3+x         AG

\n

 

\n

METHOD 2

\n

attempt to use chain rule y=±x3+x         M1

\n

dydx=±12x3+x-123x2+1         A1A1

\n

 

\n

Note: Award A1 for ±12x3+x-12, A1 for 3x2+1

\n

 

\n

dydx=±3x2+12x3+x         AG

\n

 

\n

[3 marks]

\n
d.i.
\n
\n

EITHER

\n

local minima/maxima occur whendydx=0

1+3x2=0 has no (real) solutions (or equivalent)         R1

\n


OR

\n

x20 3x2+1>0, so dydx0          R1

\n


THEN

\n

so, no local minima/maxima exist          AG

\n

 

\n

[1 mark]

\n
d.ii.
\n
\n

EITHER

\n

attempt to use quotient rule to find d2ydx2          M1

\n

d2ydx2=±12xx+x3-1+3x2x+x3-121+3x24x+x3          A1A1

\n


Note:
Award A1 for correct 12xx+x3 and correct denominator, A1 for correct -1+3x2x+x3-121+3x2.

\n

Note: Future A marks may be awarded if the denominator is missing or incorrect.

\n


stating or using d2ydx2=0 (may be seen anywhere)           (M1)

\n

12xx+x3=1+3x2x+x3-121+3x2

\n


OR

\n

attempt to use product rule to find d2ydx2          M1

\n

d2ydx2=123x2+1-123x2+1x3+x-32+3xx3+x-12          A1A1

\n


Note:
Award A1 for correct first term, A1 for correct second term.

\n


setting d2ydx2=0           (M1)

\n


OR

\n

attempts implicit differentiation on 2ydydx=3x2+1          M1

\n

2dydx2+2yd2ydx2=6x          A1

\n

recognizes that d2ydx2=0           (M1)

\n

dydx=±3x

\n

±3x2+12x3+x=±3x           (A1)

\n


THEN

\n

12xx+x3=1+3x22

\n

12x2+12x4=9x4+6x2+1

\n

3x4+6x2-1=0          A1

\n

attempt to use quadratic formula or equivalent           (M1)

\n

x2=-6±486

\n

x>0x=23-33 p=2, q=-3, r=3          A1

\n

 

\n

Note: Accept any integer multiple of p, q and r (e.g. 4,-6 and 6).

\n

 

\n

[7 marks]

\n
e.
\n
\n

attempt to find tangent line through -1, -1           (M1)

\n

y+1=-32x+1  OR  y=-1.5x-2.5           A1

\n

 

\n

[2 marks]

\n
f.i.
\n
\n

attempt to solve simultaneously with y2=x3+2           (M1)

\n


Note: The M1 mark can be awarded for an unsupported correct answer in an incorrect format (e.g. (4.25, -8.875)).

\n


obtain 174,-718           A1

\n

 

\n

[2 marks]

\n
f.ii.
\n
\n

attempt to find equation of [QS]           (M1)

\n

y-1x+1=-7942=-1.88095           (A1)

\n

solve simultaneously with y2=x3+2           (M1)

\n

x=0.28798=127441        A1

\n

y=-1.4226=131759261        A1

\n

0.228,-1.42

\n

 

\n

OR

\n

attempt to find vector equation of [QS]           (M1)

\n

xy=-11+λ214-798           (A1)

\n

x=-1+214λ

\n

y=1-798λ

\n

attempt to solve 1-798λ2=-1+214λ3+2           (M1)

\n

λ=0.2453

\n

x=0.28798=127441        A1

\n

y=-1.4226=131759261        A1

\n

0.228,-1.42

\n

 

\n

[5 marks]

\n
g.
\n
", "Examiners report": "
\n

This was a relatively straightforward start, though it was disappointing to see so many candidates sketch their graphs on two separate axes, despite the question stating they should be sketched on the same axes.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n

Of those candidates producing clear sketches, the vast majority were able to recognise the points of inflexion and write down their coordinates. A small number embarked on a mostly fruitless algebraic approach rather than use their graphs as intended. The distinguishing features between curves tended to focus on points of intersection with the axes, which was accepted. Only a small number offered ideas such as y on both curves. A number of (incorrect) suggestions were seen, stating that both curves tended towards a linear asymptote.

\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n

A majority of candidates' suggestions related to the number of intersection points with the coordinate axes, while the idea of the x-axis acting as a line of symmetry was also often seen.

\n
c.
\n
\n

The required differentiation was straightforward for the majority of candidates.

\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n

The majority employed the quotient rule here, often doing so successfully to find a correct expression for d2ydx2. Despite realising that d2ydx2=0, the resulting algebra to find the required solution proved a step too far for most. A number of slips were seen in candidates' working, though better candidates were able to answer the question confidently.

\n
e.
\n
\n

Mistakes proved to be increasingly common by this stage of the paper. Various equations of lines were suggested, with the incorrect y=1.5x+2.5 appearing more than once. Only the better candidates were able to tackle the final part of the question with any success; it was pleasing to see a number of clear algebraic (only) approaches, though this was not necessary to obtain full marks.

\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
\n

Significant work on this question part was rarely seen, and it may have been the case that many candidates chose to spend their remaining time on the second question, especially if they felt they were making little progress with part f. Having said that, correct final answers were seen from better candidates, though these were few and far between.

\n
g.
\n
", "question_id": "22M.3.AHL.TZ2.1", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-3-graphing", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion", "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

This question asks you to investigate conditions for the existence of complex roots of polynomial equations of degree 3 and 4.

\n

 
The cubic equation x3+px2+qx+r=0, where p, q, r  , has roots α, β and γ.

\n
\n

Consider the equation x3-7x2+qx+1=0, where q.

\n
\n

Noah believes that if p23q then α, β and γ are all real.

\n
\n

Now consider polynomial equations of degree 4.

\n

The equation x4+px3+qx2+rx+s=0, where p, q, r, s, has roots α, β, γ and δ.

\n

In a similar way to the cubic equation, it can be shown that:

\n

p=-(α+β+γ+δ)

\n

q=αβ+αγ+αδ+βγ+βδ+γδ

\n

r=-(αβγ+αβδ+αγδ+βγδ)

\n

s=αβγδ.

\n
\n

The equation x4-9x3+24x2+22x-12=0, has one integer root.

\n
\n

By expanding x-αx-βx-γ show that:

\n

p=-α+β+γ

\n

q=αβ+βγ+γα

\n

r=-αβγ.

\n
[3]
\n
a.
\n
\n

Show that p2-2q=α2+β2+γ2.

\n
[3]
\n
b.i.
\n
\n

Hence show that α-β2+β-γ2+γ-α2=2p2-6q.

\n
[3]
\n
b.ii.
\n
\n

Given that p2<3q, deduce that α, β and γ cannot all be real.

\n
[2]
\n
c.
\n
\n

Using the result from part (c), show that when q=17, this equation has at least one complex root.

\n
[2]
\n
d.
\n
\n

By varying the value of q in the equation x3-7x2+qx+1=0, determine the smallest positive integer value of q required to show that Noah is incorrect.

\n
[2]
\n
e.i.
\n
\n

Explain why the equation will have at least one real root for all values of q.

\n
[1]
\n
e.ii.
\n
\n

Find an expression for α2+β2+γ2+δ2 in terms of p and q.

\n
[3]
\n
f.i.
\n
\n

Hence state a condition in terms of p and q that would imply x4+px3+qx2+rx+s=0 has at least one complex root.

\n
[1]
\n
f.ii.
\n
\n

Use your result from part (f)(ii) to show that the equation x4-2x3+3x2-4x+5=0 has at least one complex root.

\n
[1]
\n
g.
\n
\n

State what the result in part (f)(ii) tells us when considering this equation x4-9x3+24x2+22x-12=0.

\n
[1]
\n
h.i.
\n
\n

Write down the integer root of this equation.

\n
[1]
\n
h.ii.
\n
\n

By writing x4-9x3+24x2+22x-12 as a product of one linear and one cubic factor, prove that the equation has at least one complex root.

\n
[4]
\n
h.iii.
\n
", "Markscheme": "
\n

attempt to expand x-αx-βx-γ            M1

\n

=x2-α+βx+αβx-γ  OR  =x-αx2-β+γx+βγ         A1

\n

x3+px2+qx+r=x3-α+β+γx2+αβ+βγ+γαx-αβγ         A1

\n

comparing coefficients:

\n

p=-α+β+γ         AG 

\n

q=αβ+βγ+γα         AG 

\n

r=-αβγ         AG 

\n

 

\n

Note: For candidates who do not include the AG lines award full marks.

\n

 

\n

[3 marks]

\n
a.
\n
\n

p2-2q=α+β+γ2-2αβ+βγ+γα            (A1)

\n

attempt to expand α+β+γ2            (M1)

\n

=α2+β2+γ2+2αβ+βγ+γα-2αβ+βγ+γα or equivalent         A1

\n

=α2+β2+γ2         AG 

\n

 

\n

Note: Accept equivalent working from RHS to LHS.

\n

 

\n

[3 marks]

\n
b.i.
\n
\n

EITHER

\n

attempt to expand α-β2+β-γ2+γ-α2            (M1)

\n

=α2+β2-2αβ+β2+γ2-2βγ+γ2+α2-2γα         A1

\n

=2α2+β2+γ2-2αβ+βγ+γα

\n

=2p2-2q-2q or equivalent         A1

\n

=2p2-6q         AG 

\n


OR

\n

attempt to write 2p2-6q in terms of α, β, γ            (M1)

\n

=2p2-2q-2q

\n

=2α2+β2+γ2-2αβ+βγ+γα         A1

\n

=α2+β2-2αβ+β2+γ2-2βγ+γ2+α2-2γα         A1

\n

=α-β2+β-γ2+γ-α2         AG 

\n

 

\n

Note: Accept equivalent working where LHS and RHS are expanded to identical expressions.

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

p2<3q2p2-6q<0

\n

α-β2+β-γ2+γ-α2<0         A1

\n

if all roots were real α-β2+β-γ2+γ-α20         R1

\n


Note:
Condone strict inequality in the R1 line.
Note: Do not award A0R1.

\n


roots cannot all be real         AG 

\n

 

\n

[2 marks]

\n
c.
\n
\n

p2=-72=49 and 3q=51         A1

\n

so p2<3q the equation has at least one complex root         R1

\n

 

\n

Note: Allow equivalent comparisons; e.g. checking p2<6q

\n

 

\n

[2 marks]

\n
d.
\n
\n

use of GDC (eg graphs or tables)         (M1)

\n

q=12         A1

\n

 

\n

[2 marks]

\n
e.i.
\n
\n

complex roots appear in conjugate pairs (so if complex roots occur the other root will be real OR all 3 roots will be real).

\n

OR

\n

a cubic curve always crosses the x-axis at at least one point.       R1

\n

 

\n

[1 mark]

\n
e.ii.
\n
\n

attempt to expand α+β+γ+δ2           (M1)

\n

α+β+γ+δ2=α2+β2+γ2+δ2+2αβ+αγ+αδ+βγ+βδ+γδ           (A1)

\n

α2+β2+γ2+δ2=α+β+γ+δ2-2αβ+αγ+αδ+βγ+βδ+γδ

\n

α2+β2+γ2+δ2=p2-2q          A1

\n

 

\n

[3 marks]

\n
f.i.
\n
\n

p2<2q  OR  p2-2q<0          A1

\n

 

\n

Note: Allow FT on their result from part (f)(i).

\n

 

\n

[1 mark]

\n
f.ii.
\n
\n

4<6  OR  22-2×3<0          R1

\n

hence there is at least one complex root.         AG

\n

 

\n

Note: Allow FT from part (f)(ii) for the R mark provided numerical reasoning is seen.

\n

 

\n

[1 mark]

\n
g.
\n
\n

p2>2q 81>2×24  (so) nothing can be deduced         R1

\n

 

\n

Note: Do not allow FT for the R mark.

\n

 

\n

[1 mark]

\n
h.i.
\n
\n

-1          A1

\n

 

\n

[1 mark]

\n
h.ii.
\n
\n

attempt to express as a product of a linear and cubic factor           M1

\n

x+1x3-10x2+34x-12          A1A1

\n

 

\n

Note: Award A1 for each factor. Award at most A1A0 if not written as a product.

\n

 

\n

since for the cubic, p2<3q 100<102          R1

\n

there is at least one complex root          AG

\n

 

\n

[4 marks]

\n
h.iii.
\n
", "Examiners report": "
\n

The first part of this question proved to be very accessible, with the majority of candidates expanding their brackets as required, to find the coefficients p, q and r.

\n
a.
\n
\n

The first part of this question was usually answered well, though presentation in the second part sometimes left a lot to be desired. The expression 2p2-2q-2q was expected to be seen more often, as a 'pivot' to reaching the required result. Algebra was often lengthy, but untidily so, sometimes leaving examiners to do some mental tidying up on behalf of the candidate.

\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n

A good number of candidates recognised the reasoning required in this part of the question and were able to score both marks.

\n
c.
\n
\n

Most candidates found applying this specific case to be very straightforward.

\n
d.
\n
\n

Most candidates offered incorrect answers in the first part; despite their working suggested utilisation of the GDC, it was clear that many did not appreciate what the question was asking. The second part was usually answered well, with the idea of complex roots occurring in conjugate pairs being put to good use.

\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
\n

Some very dubious algebra was seen here, and often no algebra at all. Despite this, a good number of candidates seemed to make the 'leap' to the correct expression p2-2q, perhaps fortuitously so in a number of cases.

\n
f.i.
\n
\n[N/A]\n
f.ii.
\n
\n

Of those finding p2-2q in part f, a surprising number of answers seen employed the test of checking whether p2<3q.

\n
g.
\n
\n

Part i was usually not answered successfully, which may have been due to shortage of time. However, it was pleasing to see a number of candidates reach the end of the paper and successfully factorise the given quartic using a variety of methods. The final part required the p2<3q test. Though correct reasoning was sometimes seen, it was rare for this final mark to be gained.

\n
h.i.
\n
\n[N/A]\n
h.ii.
\n
\n[N/A]\n
h.iii.
\n
", "question_id": "22M.3.AHL.TZ2.2", "topics": [ "topic-1-number-and-algebra", "topic-2-functions" ], "subtopics": [ "sl-1-6-simple-proof", "ahl-1-14-complex-roots-of-polynomials-conjugate-roots-de-moivres-powers-&-roots-of-complex-numbers", "ahl-1-15-proof-by-induction-contradiction-counterexamples", "ahl-2-12-factor-and-remainder-theorems-sum-and-product-of-roots" ] }, { "Question": "
\n

All lengths in this question are in centimetres.

\n

A solid metal ornament is in the shape of a right pyramid, with vertex V and square base ABCD. The centre of the base is X. Point V has coordinates (1, 5, 0) and point A has coordinates (-1, 1, 6).

\n

\n
\n

The volume of the pyramid is 57.2cm3, correct to three significant figures.

\n
\n

Find AV.

\n
[2]
\n
a.
\n
\n

Given that AV^B=40°, find AB.

\n
[3]
\n
b.
\n
\n

Find the height of the pyramid, VX.

\n
[3]
\n
c.
\n
\n

A second ornament is in the shape of a cuboid with a rectangular base of length 2xcm, width xcm and height ycm. The cuboid has the same volume as the pyramid.

\n

The cuboid has a minimum surface area of Scm2. Find the value of S.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

attempt to use the distance formula to find AV         (M1)

\n

1--12+5-12+0-62

\n

=7.48331

\n

=7.48cm  =56  or  214           A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

attempt to apply cosine rule OR sine rule to find AB            (M1)

\n

AB=7.482+7.482-2×7.48×7.48cos40°  OR  ABsin40°=56sin70°           (A1)

\n

=5.11888

\n

=5.12cm          A1

\n

 

\n

METHOD 2

\n

Let M be the midpoint of [AB]

\n

attempt to apply right-angled trigonometry on triangle AVM            (M1)

\n

=2×7.48×sin20°           (A1)

\n

 =5.11888

\n

=5.12cm          A1

\n

 

\n

[3 marks]

\n
b.
\n
\n

METHOD 1

\n

equating volume of pyramid formula to 57.2           (M1)

\n

13×5.112×h=57.2           (A1)

\n

h=6.54886

\n

h=6.55cm          A1

\n

 

\n

METHOD 2

\n

Let M be the midpoint of [AB]

\n

AV2=AM2+MX2+XV2           (M1)

\n

XV=7.482-5.1122-5.1122           (A1)

\n

h=6.54886

\n

h=6.55cm          A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

V=x×2x×y=57.2           (A1)

\n

S=22x2+xy+2xy           A1

\n

 

\n

Note: Condone use of A.

\n


attempt to substitute y=57.22x2 into their expression for surface area           (M1)

\n

Sx= 4x2+6x57.22x2

\n


EITHER

\n

attempt to find minimum turning point on graph of area function           (M1)

\n


OR

\n

dSdx=8x-171.6x-2=0  OR  x=2.77849           (M1)

\n


THEN

\n

92.6401

\n

minimum surface area =92.6cm2          A1

\n

 

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n

Parts (a), (b) and (c) were completed well by many candidates, but few were able to make any significant progress in part (d).

\n

In part (a), many candidates were able to apply the distance formula and successfully find AV. However, a common error was to work in two-dimensions and to apply Pythagoras' Theorem once, neglecting completely the z-coordinates. Many recognised the need to use either the sine or cosine rule in part (b) to find the length AB. Common errors in this part included: the GDC being set incorrectly in radians; applying right-angled trigonometry on a 40°, 40°, 70° triangle; or using 12AB as the length of AX in triangle AVX.

\n

Despite the formula for the volume of a pyramid being in the formula booklet, a common error in part (c) was to omit the factor of 13 from the volume formula, or not to recognise that the area of the base of the pyramid was AB2.

\n

The most challenging part of this question proved to be the optimization of the surface area of the cuboid in part (d). Although some candidates were able to form an equation involving the volume of the cuboid, an expression for the surface area eluded most. A common error was to gain a surface area which involved eight sides rather than six. It was surprising that few who were able to find both the equation and an expression were able to progress any further. Of those that did, few used their GDC to find the minimum surface area directly, with most preferring the more time consuming analytical approach.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "22M.2.SL.TZ1.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints", "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A function, f, has its derivative given by f(x)=3x2-12x+p, where p. The following diagram shows part of the graph of f.

\n

\n

The graph of f has an axis of symmetry x=q.

\n
\n

The vertex of the graph of f lies on the x-axis.

\n
\n

The graph of f has a point of inflexion at x=a.

\n
\n

Find the value of q.

\n
[2]
\n
a.
\n
\n

Write down the value of the discriminant of f.

\n
[1]
\n
b.i.
\n
\n

Hence or otherwise, find the value of p.

\n
[3]
\n
b.ii.
\n
\n

Find the value of the gradient of the graph of f at x=0.

\n
[3]
\n
c.
\n
\n

Sketch the graph of f, the second derivative of f. Indicate clearly the x-intercept and the y-intercept.

\n
[2]
\n
d.
\n
\n

Write down the value of a.

\n
[1]
\n
e.i.
\n
\n

Find the values of x for which the graph of f is concave-down. Justify your answer.

\n
[2]
\n
e.ii.
\n
", "Markscheme": "
\n

EITHER

\n

attempt to use x=-b2a          (M1)

\n

q=--122×3

\n


OR

\n

attempt to complete the square          (M1)

\n

3x-22-12+p

\n


OR

\n

attempt to differentiate and equate to 0          (M1)

\n

f''x=6x-12=0

\n


THEN

\n

q=2         A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

discriminant =0        A1

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

EITHER

\n

attempt to substitute into b2-4ac        (M1)

\n

-122-4×3×p=0        A1

\n


OR

\n

f'(2)=0       (M1)

\n

-12+p=0        A1

\n


THEN

\n

p=12        A1

\n

 

\n

[3 marks]

\n
b.ii.
\n
\n

f''x=6x-12        A1

\n

attempt to find f''0        (M1)

\n

=6×0-12

\n

gradient =-12        A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

        A1A1

\n


Note:
Award A1 for line with positive gradient, A1 for correct intercepts.

\n

 

\n

[2 marks]

\n
d.
\n
\n

a=2        A1

\n

 

\n

[1 mark]

\n
e.i.
\n
\n

x<2        A1

\n

f''x<0 (for x<2)  OR  the f'' is below the x-axis (for x<2)

\n

OR    f''  (sign diagram must be labelled f'')        R1

\n

 

\n

[2 marks]

\n
e.ii.
\n
", "Examiners report": "
\n

Candidates did score well on this question. As always, candidates are encouraged to read the questions carefully for key words such as 'value' as opposed to 'expression'. So, if asked for the value of the discriminant, their answer should be a number and not an expression found from b2-4ac. As such the value of the discriminant in (b)(i) was often seen in (b)(ii). Please ask students to use a straight edge when sketching a straight line! Overall, the reasoning mark for determining where the graph of f is concave-down, was an improvement on previous years. Sign diagrams were typically well labelled, and the description contained clarity regarding which function was being referred to.

\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.i.
\n
\n[N/A]\n
e.ii.
\n
", "question_id": "22M.1.SL.TZ1.7", "topics": [ "topic-5-calculus", "topic-2-functions" ], "subtopics": [ "sl-5-7-the-second-derivative", "sl-2-6-quadratic-function", "sl-2-3-graphing" ] }, { "Question": "
\n

The function f is defined by fx=4x+1x+4, where x, x-4.

\n
\n

For the graph of f

\n
\n

The graphs of f and f-1 intersect at x=p and x=q, where p<q.

\n
\n

write down the equation of the vertical asymptote.

\n
[1]
\n
a.i.
\n
\n

find the equation of the horizontal asymptote.

\n
[2]
\n
a.ii.
\n
\n

Find f-1x.

\n
[4]
\n
b.i.
\n
\n

Using an algebraic approach, show that the graph of f-1 is obtained by a reflection of the graph of f in the y-axis followed by a reflection in the x-axis.

\n
[4]
\n
b.ii.
\n
\n

Find the value of p and the value of q.

\n
[2]
\n
c.i.
\n
\n

Hence, find the area enclosed by the graph of f and the graph of f-1.

\n
[3]
\n
c.ii.
\n
", "Markscheme": "
\n

x=-4          A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

attempt to substitute into y=ac  OR  table with large values of x  OR  sketch of f showing asymptotic behaviour          (M1)

\n

y=4          A1

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

y=4x+1x+4

\n

attempt to interchange x and y (seen anywhere)        M1

\n

xy+4y=4x+1   OR   xy+4x=4y+1         (A1)

\n

xy-4x=1-4y   OR   xy-4y=1-4x         (A1)

\n

f-1x=1-4xx-4  (accept y=1-4xx-4)         A1

\n

 

\n

[4 marks]

\n
b.i.
\n
\n

reflection in y-axis given by f-x         (M1)

\n

f-x=-4x+1-x+4         (A1)

\n

reflection of their f-x in x-axis given by -f-x accept \"now -fx\"        M1

\n

-f-x= --4x+1-x+4

\n

=-4x+1x-4  OR  4x-1-x+4         A1

\n

=1-4xx-4  =f-1x         AG

\n

 

\n

Note: If the candidate attempts to show the result using a particular coordinate on the graph of f rather than a general coordinate on the graph of f, where appropriate, award marks as follows:
M0A0 for eg (2,3)(2,3)
M0A0 for (2,3)(2,3)

\n

 

\n

[4 marks]

\n
b.ii.
\n
\n

attempt to solve fx=f-1x using graph or algebraically         (M1)

\n

p=-1  AND  q=1         A1

\n

 

\n

Note: Award (M1)A0 if only one correct value seen.

\n

 

\n

[2 marks]

\n
c.i.
\n
\n

attempt to set up an integral to find area between f and f-1         (M1)

\n

-114x+1x+4-1-4xx-4dx         (A1)

\n

=0.675231

\n

=0.675         A1

\n

 

\n

[3 marks]

\n
c.ii.
\n
", "Examiners report": "
\n

Candidates mostly found the first part of this question accessible, with many knowing how to find the equation of both asymptotes. Common errors included transposing the asymptotes, or finding where an asymptote occurred but not giving it as an equation.

\n

Candidates knew how to start part (b)(i), with most attempting to find the inverse function by firstly interchanging x and y. However, many struggled with the algebra required to change the subject, and were not awarded all the marks. A common error in this part was for candidates to attempt to find an expression for f'(x), rather than one for f-1(x). Few candidates were able to answer part (b)(ii). Many appeared not to know that a reflection in the y-axis is given by f(-x), or that a reflection in the x-axis is given by -f(x). Many of those that did, multiplied both the numerator and denominator by -1 when taking the negative of their f(-x) , i.e. --4x+1-x+4 was often simplified as 4x-1x-4. However, the majority of candidates either did not attempt this question part or attempted to describe a graphical approach often involving a specific point, rather than an algebraic approach.

\n

Those that attempted part (c), and had the correct expression for f-1(x), were usually able to gain all the marks. However, those that had an incorrect expression, or had found f'(x), often proceeded to find an area, even when there was not an area enclosed by their two curves.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
", "question_id": "22M.2.SL.TZ1.8", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-8-reciprocal-and-simple-rational-functions-equations-of-asymptotes", "sl-2-5-composite-functions-identity-finding-inverse", "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-11-definite-integrals-areas-under-curve-onto-x-axis-and-areas-between-curves" ] }, { "Question": "
\n

Consider the series lnx+plnx+13lnx+, where x, x>1 and p, p0.

\n
\n

Consider the case where the series is geometric.

\n
\n

Now consider the case where the series is arithmetic with common difference d.

\n
\n

Show that p=±13.

\n
[2]
\n
a.i.
\n
\n

Given that p>0 and S=3+3, find the value of x.

\n
[3]
\n
a.ii.
\n
\n

Show that p=23.

\n
[3]
\n
b.i.
\n
\n

Write down d in the form klnx, where k.

\n
[1]
\n
b.ii.
\n
\n

The sum of the first n terms of the series is -3lnx.

\n

Find the value of n.

\n
[6]
\n
b.iii.
\n
", "Markscheme": "
\n

EITHER

\n

attempt to use a ratio from consecutive terms        M1

\n

plnxlnx=13lnxplnx  OR  13lnx=lnxr2  OR  plnx=lnx13p

\n

 

\n

Note: Candidates may use lnx1+lnxp+lnx13 and consider the powers of x in geometric sequence

\n

Award M1 for p1=13p.

\n


OR

\n

r=p  and  r2=13        M1

\n


THEN

\n

p2=13  OR  r=±13          A1

\n

p=±13          AG

\n

 

\n

Note: Award M0A0 for r2=13 or p2=13 with no other working seen.

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

lnx1-13  =3+3           (A1)

\n

lnx=3-33+3-33  OR  lnx=3-3+3-1  lnx=2          A1

\n

x=e2          A1

\n

 

\n

[3 marks]

\n
a.ii.
\n
\n

METHOD 1

\n

attempt to find a difference from consecutive terms or from u2          M1

\n

correct equation          A1

\n

plnx-lnx=13lnx-plnx  OR  13lnx=lnx+2plnx-lnx

\n


Note:
Candidates may use lnx1+lnxp+lnx13+ and consider the powers of x in arithmetic sequence.

\n

Award M1A1 for p-1=13-p

\n

 

\n

2plnx=43lnx  2p=43          A1

\n

p=23          AG

\n

 

\n

METHOD 2

\n

attempt to use arithmetic mean u2=u1+u32          M1

\n

plnx=lnx+13lnx2          A1

\n

2plnx=43lnx  2p=43          A1

\n

p=23          AG

\n

 

\n

METHOD 3

\n

attempt to find difference using u3          M1

\n

13lnx=lnx+2d  d=-13lnx

\n

 

\n

u2=lnx+1213lnx-lnx  OR  plnx-lnx=-13lnx          A1

\n

plnx=23lnx          A1

\n

p=23          AG

\n

 

\n

[3 marks]

\n
b.i.
\n
\n

d=-13lnx       A1

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

METHOD 1

\n

Sn=n22lnx+n-1×-13lnx

\n

attempt to substitute into Sn and equate to -3lnx           (M1)

\n

n22lnx+n-1×-13lnx=-3lnx

\n

correct working with Sn (seen anywhere)           (A1)

\n

n22lnx-n3lnx+13lnx  OR  nlnx-nn-16lnx  OR  n2lnx+4-n3lnx

\n

correct equation without lnx          A1

\n

n273-n3=-3  OR  n-nn-16=-3 or equivalent

\n


Note:
Award as above if the series 1+p+13+ is considered leading to n273-n3=-3.

\n


attempt to form a quadratic =0           (M1)

\n

n2-7n-18=0

\n

attempt to solve their quadratic           (M1)

\n

n-9n+2=0

\n

n=9          A1

\n

 

\n

METHOD 2

\n

listing the first 7 terms of the sequence           (A1)

\n

lnx+23lnx+13lnx+0-13lnx-23lnx-lnx+

\n

recognizing first 7 terms sum to 0           M1

\n

8th term is -43lnx           (A1)

\n

9th term is -53lnx           (A1)

\n

sum of 8th and 9th term =-3lnx           (A1)

\n

n=9          A1

\n

 

\n

[6 marks]

\n
b.iii.
\n
", "Examiners report": "
\n

Many candidates were able to identify the key relationship between consecutive terms for both geometric and arithmetic sequences. Substitution into the infinity sum formula was good with solving involving the natural logarithm done quite well. The complexity of the equation formed using 𝑆𝑛 was a stumbling block for some candidates. Those who factored out and cancelled the ln𝑥 expression were typically successful in solving the resulting quadratic.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
", "question_id": "22M.1.SL.TZ1.8", "topics": [ "topic-1-number-and-algebra", "topic-2-functions" ], "subtopics": [ "sl-1-2-arithmetic-sequences-and-series", "sl-1-3-geometric-sequences-and-series", "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

Consider fx=4cosx1-3cos2x+3cos22x-cos32x.

\n
\n

Expand and simplify (1-a)3 in ascending powers of a.

\n
[2]
\n
a.i.
\n
\n

By using a suitable substitution for a, show that 1-3cos2x+3cos22x-cos32x=8sin6x.

\n
[4]
\n
a.ii.
\n
\n

Show that 0mfxdx=327sin7m, where m is a positive real constant.

\n
[4]
\n
b.i.
\n
\n

It is given that mπ2fxdx=12728, where 0mπ2. Find the value of m.

\n
[5]
\n
b.ii.
\n
", "Markscheme": "
\n

EITHER

\n

attempt to use binomial expansion           (M1)

\n

1+C13×1×-a+C23×1×-a2+1×-a3

\n


OR

\n

1-a1-a1-a

\n

=1-a1-2a+a2           (M1)

\n


THEN

\n

=1-3a+3a2-a3          A1

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

a=cos2x                   (A1)

\n

So, 1-3cos2x+3cos22x-cos32x=

\n

1-cos2x3             A1

\n

attempt to substitute any double angle rule for cos2x into 1-cos2x3                   (M1)

\n

=2sin2x3             A1

\n

=8sin6x             AG

\n


Note: Allow working RHS to LHS.

\n

 

\n

[4 marks]

\n
a.ii.
\n
\n

recognizing to integrate 4cosx×8sin6xdx                   (M1)

\n


EITHER

\n

applies integration by inspection                   (M1)

\n

32cosx×sinx6dx

\n

=327sin7x+c             A1

\n

327sin7x0m   =327sin7m-327sin70             A1

\n


OR

\n

u=sinxdudx=cosx                   (M1)

\n

32cosxsin6xdx=32u6du

\n

=327u7+c             A1

\n

327sin7x0m   OR   327u70sinm   =327sin7m-327sin70             A1

\n


THEN

\n

=327sin7m             AG

\n

 

\n

[4 marks]

\n
b.i.
\n
\n

EITHER

\n

mπ2fxdx=327sin7xmπ2=327sin7π2-327sin7m                   M1

\n

327sin7π2-327sin7m=12728  OR  3271-sin7m=12728                   (M1)

\n


OR

\n

0π2fxdx=0mfxdx+mπ2fxdx                   M1

\n

327=327sin7m+12728                   (M1)

\n


THEN

\n

sin7m=1128  =127                   (A1)

\n

sinm=12                   (A1)

\n

m=π6             A1

\n

 

\n

[5 marks]

\n
b.ii.
\n
", "Examiners report": "
\n

Many candidates successfully expanded the binomial, with the most common error being to omit the negative sign with a. The connection between (a)(i) and (ii) was often noted but not fully utilised with candidates embarking on unnecessary complex algebraic expansions of expressions involving double angle rules. Candidates often struggled to apply inspection or substitution when integrating. As a 'show that' question, b(i) provided a useful result to be utilised in (ii). So even without successfully completing (i) candidates could apply it in part (ii). Not many managed to do so.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "22M.1.SL.TZ1.9", "topics": [ "topic-3-geometry-and-trigonometry", "topic-1-number-and-algebra" ], "subtopics": [ "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule", "sl-1-9-binomial-theorem-where-n-is-an-integer", "sl-1-6-simple-proof" ] }, { "Question": "
\n

Consider the points A(-2, 20), B(4, 6) and C(-14, 12). The line L passes through the point A and is perpendicular to [BC].

\n
\n

Find the equation of L.

\n
[3]
\n
a.
\n
\n

The line L passes through the point (k, 2).

\n

Find the value of k.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

mBC=12-6-14-4 =-13        (A1)

\n

finding mL=-1mBC using their mBC        (M1)

\n

mL=3

\n

y-20=3x+2,  y=3x+26        A1

\n

 

\n

Note: Do not accept L=3x+26

\n

 

\n

[3 marks]

\n
a.
\n
\n

substituting (k, 2) into their L        (M1)

\n

2-20=3k+2  OR  2=3k+26

\n

k=-8        A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n

Finding the gradient of a line was well understood and many candidates also correctly found the perpendicular slope. Even with an error in their part (a), follow through marks in part (b) allowed many candidates to earn full marks for finding k despite their incorrect equation resulting in arithmetic of greater complexity.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.SL.TZ1.1", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-1-equations-of-straight-lines-parallel-and-perpendicular" ] }, { "Question": "
\n

A bakery makes two types of muffins: chocolate muffins and banana muffins.

\n

The weights, C grams, of the chocolate muffins are normally distributed with a mean of 62g and standard deviation of 2.9g.

\n
\n

The weights, B grams, of the banana muffins are normally distributed with a mean of 68g and standard deviation of 3.4g.

\n

Each day 60% of the muffins made are chocolate.

\n

On a particular day, a muffin is randomly selected from all those made at the bakery.

\n
\n

The machine that makes the chocolate muffins is adjusted so that the mean weight of the chocolate muffins remains the same but their standard deviation changes to σg. The machine that makes the banana muffins is not adjusted. The probability that the weight of a randomly selected muffin from these machines is less than 61g is now 0.157.

\n
\n

Find the probability that a randomly selected chocolate muffin weighs less than 61g.

\n
[2]
\n
a.
\n
\n

In a random selection of 12 chocolate muffins, find the probability that exactly 5 weigh less than 61g.

\n
[2]
\n
b.
\n
\n

Find the probability that the randomly selected muffin weighs less than 61g.

\n
[4]
\n
c.i.
\n
\n

Given that a randomly selected muffin weighs less than 61g, find the probability that it is chocolate.

\n
[3]
\n
c.ii.
\n
\n

Find the value of σ.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

PC<61         (M1)

\n

=0.365112

\n

=0.365         A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

recognition of binomial eg  X~B12,0.365         (M1)

\n

PX=5=0.213666

\n

=0.214         A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

Let CM represent ‘chocolate muffin’ and BM represent ‘banana muffin’

\n

P(B<61)=0.0197555...         (A1)

\n


EITHER

\n

PCM×PC<61CM+PBM×PB<61BM  (or equivalent in words)         (M1)

\n


OR

\n

tree diagram showing two ways to have a muffin weigh <61         (M1)

\n


THEN

\n

0.6×0.365+0.4×0.0197         (A1)

\n

=0.226969

\n

=0.227         A1

\n

 

\n

[4 marks]

\n
c.i.
\n
\n

recognizing conditional probability         (M1)

\n

 

\n

Note: Recognition must be shown in context either in words or symbols, not just PAB

\n

 

\n

0.6×0.3651120.226969         (A1)

\n

=0.965183

\n

=0.965         A1

\n

 

\n

[3 marks]

\n
c.ii.
\n
\n

METHOD 1

\n

PCM×PC<61CM×PBM×PB<61BM=0.157         (M1)

\n

0.6×PC<61+0.4×0.0197555=0.157

\n

PC<61=0.248496         (A1)

\n

attempt to solve for σ using GDC         (M1)

\n


Note:
Award (M1) for a graph or table of values to show their PC<61 with a variable standard deviation.

\n


σ=1.47225

\n

σ=1.47g         A2

\n

 

\n

METHOD 2

\n

PCM×PC<61CM×PBM×PB<61BM=0.157         (M1)

\n

0.6×PC<61+0.4×0.0197555=0.157

\n

PC<61=0.248496         (A1)

\n

use of inverse normal to find z score of their PC<61         (M1)

\n

z=-0.679229

\n

correct substitution         (A1)

\n

61-62σ=-0.679229

\n

σ=1.47225

\n

σ=1.47g         A1

\n

 

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n

This question was common to both HL and SL papers.

\n

The first two parts of this question were generally well done, with many candidates demonstrating an understanding of how to find, using their GDC, the required probability from a normal distribution in part (a), and recognising the binomial probability in part (b).

\n

Parts (c) and (d) were not done well, although many that were able to make progress in part (d) were often able to give concise solutions. Most that attempted part (c) did very poorly, while few attempted part (d). Both parts proved challenging, principally due to difficulties in determining the different possible outcomes with combined events. In part (c)(i), tree diagrams were unfortunately rarely seen, as were attempts to set out the ways of selecting a muffin weighing less than 61 g, either in words, or using appropriate notation involving probabilities. Those who did understand these concepts on the other hand were much more likely to be able to find the conditional probability in part (c)(ii) and be successful in part (d). Common errors included not considering both types of muffin, and in part (d) using a probability instead of a z-value.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
", "question_id": "22M.2.SL.TZ1.9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-9-normal-distribution-and-calculations", "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams", "sl-4-8-binomial-distribution", "sl-4-12-z-values-inverse-normal-to-find-mean-and-standard-deviation" ] }, { "Question": "
\n

Find the value of 193x-5xdx.

\n
", "Markscheme": "
\n

3x-5xdx=3-5x-12dx             (A1)

\n

3x-5xdx=3x-10x12+c             A1A1

\n

substituting limits into their integrated function and subtracting             (M1)

\n

39-10912-31-10112  OR  27-10×3-3-10

\n

=4             A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n

A mixed response was noted for this question. Candidates who simplified the algebraic fraction before integrating were far more successful in gaining full marks in this question. Many candidates used other valid approaches such as integration by substitution and integration by parts with varying degrees of success. A small number of candidates substituted the limits without integrating.

\n
", "question_id": "22M.1.AHL.TZ1.1", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Consider the expansion of 8x3-12xn where n+. Determine all possible values of n for which the expansion has a non-zero constant term.

\n
", "Markscheme": "
\n

EITHER

\n

attempt to obtain the general term of the expansion

\n

Tr+1=Crn8x3n-r-12xr  OR  Tr+1=Cn-rn8x3r-12xn-r             (M1)

\n


OR

\n

recognize power of x starts at 3n and goes down by 4 each time             (M1)

\n


THEN

\n

recognizing the constant term when the power of x is zero (or equivalent)             (M1)

\n

r=3n4  or  n=43r  or  3n-4r=0  OR  3r-n-r=0 (or equivalent)            A1

\n

r is a multiple of 3 r=3,6,9, or one correct value of n (seen anywhere)             (A1)

\n

n=4k, k+            A1

\n


Note: Accept n is a (positive) multiple of 4 or n=4,8,12,
Do not accept n=4,8,12

\n

Note: Award full marks for a correct answer using trial and error approach
showing n=4,8,12, and for recognizing that this pattern continues.

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n

There was a mixed response to this question. Candidates who used a trial and error approach were more successful in obtaining completely correct answers than those who tried to solve algebraically by finding the general term to form an equation relating n and r . Poor explanations were often noted in the trial and error approach. Candidates often failed to make progress after obtaining n=43r in the algebraic approach. Some candidates did not attempt this question.

\n
", "question_id": "22M.1.AHL.TZ1.6", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-9-binomial-theorem-where-n-is-an-integer" ] }, { "Question": "
\n

Consider the vectors a and b such that a=12-5 and b=15.

\n
\n

Consider the vector p such that p=a+b.

\n
\n

Consider the vector q such that q=xy, where x, y+.

\n
\n

Find the possible range of values for a+b.

\n
[2]
\n
a.
\n
\n

Given that a+b is a minimum, find p.

\n
[2]
\n
b.
\n
\n

Find q such that |q|=|b| and q is perpendicular to a.

\n
[5]
\n
c.
\n
", "Markscheme": "
\n

a=122+-52=13            (A1)

\n

2a+b28  (accept min 2 and max 28)           A1

\n

 

\n

Note: Award (A1)A0 for 2 and 28 seen with no indication that they are the endpoints of an interval.

\n

 

\n

[2 marks]

\n
a.
\n
\n

recognition that p or b is a negative multiple of a            (M1)

\n

p=-2a^  OR  b=-1513a=-151312-5

\n

p=-21312-5=-1.850.769           A1

\n

 

\n

 

\n

[2 marks]

\n
b.
\n
\n

METHOD 1

\n

q is perpendicular to 12-5

\n

q is in the direction 512            (M1)

\n

q=k512            (A1)

\n

q=5k2+12k2=15            (M1)

\n

k=1513            (A1)

\n

q=1513512=751318013=5.7713.8           A1

\n

 

\n

METHOD 2

\n

q is perpendicular to 12-5

\n

attempt to set scalar product q.a=0  OR  product of gradients =-1            (M1)

\n

12x-5y=0            (A1)

\n

q=x2+y2=15

\n

attempt to solve simultaneously to find a quadratic in x or y            (M1)

\n

x2+12x52=152  OR  5y122+y2=152

\n

q=751318013=5.7713.8           A1A1

\n

Note: Award A1 independently for each value. Accept values given as x=7513 and y=18013 or equivalent.

\n

 

\n

[5 marks]

\n
c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.2.AHL.TZ1.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-3-12-vector-definitions", "ahl-3-13-scalar-(dot)-product" ] }, { "Question": "
\n

The expression 3x-5x can be written as 3-5xp. Write down the value of p.

\n
[1]
\n
a.
\n
\n

Hence, find the value of 193x-5xdx.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

3x-5x=3-5x-12       A1

\n

p=-12

\n

 

\n

[1 mark]

\n
a.
\n
\n

3x-5xdx=3x-10x12+c             A1A1

\n

substituting limits into their integrated function and subtracting             (M1)

\n

39-10912-31-10112  OR  27-10×3-3-10

\n

=4             A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n

Many candidates could give the value of p correctly. However, many did struggle with the integration, including substituting limits into the integrand, without integrating at all. An incorrect value of p often resulted in arithmetic of greater complexity.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.SL.TZ1.2", "topics": [ "topic-1-number-and-algebra", "topic-5-calculus" ], "subtopics": [ "sl-1-7-laws-of-exponents-and-logs", "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Mary, three female friends, and her brother, Peter, attend the theatre. In the theatre there is a row of 10 empty seats. For the first half of the show, they decide to sit next to each other in this row.

\n
\n

For the second half of the show, they return to the same row of 10 empty seats. The four girls decide to sit at least one seat apart from Peter. The four girls do not have to sit next to each other.

\n
\n

Find the number of ways these five people can be seated in this row.

\n
[3]
\n
a.
\n
\n

Find the number of ways these five people can now be seated in this row.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

6×5!             (A1)(A1)

\n

=720  (accept 6!)             A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

METHOD 1

\n

(Peter apart from girls, in an end seat)  P48=1680 OR

\n

(Peter apart from girls, not in end seat)  P47=840             (A1)

\n

case 1: Peter at either end 

\n

2×P48=3360  OR  2×C48×4!=3360             (A1)

\n

case 2: Peter not at the end

\n

8×P47=6720  OR  8×C47×4!=6720             (A1)

\n

Total number of ways =3360+6720

\n

=10080             A1

\n

 

\n

METHOD 2

\n

(Peter next to girl, in an end seat) 4×P38=1344  OR

\n

(Peter next to one girl, not in end seat) 2×4×P37=1680  OR

\n

(Peter next to two girls, not in end seat)  4×3×P27=504             (A1)

\n

case 1: Peter at either end

\n

2×4×P38=2688             (A1)

\n

case 2: Peter not at the end

\n

82×4×P37+4×3×P27=17472             (A1)

\n

Total number of ways =P510-2688+17472

\n

=10080             A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.AHL.TZ1.9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

Consider the function fx=x2-1, where 1x2.

\n
\n

The curve y=f(x) is rotated 2π about the y-axis to form a solid of revolution that is used to model a water container.

\n
\n

At t=0, the container is empty. Water is then added to the container at a constant rate of 0.4m3s-1.

\n
\n

Sketch the curve y=fx, clearly indicating the coordinates of the endpoints.

\n
[2]
\n
a.
\n
\n

Show that the inverse function of f is given by f-1x=x2+1.

\n
[3]
\n
b.i.
\n
\n

State the domain and range of f-1.

\n
[2]
\n
b.ii.
\n
\n

Show that the volume, Vm3, of water in the container when it is filled to a height of h metres is given by V=π13h3+h.

\n
[3]
\n
c.i.
\n
\n

Hence, determine the maximum volume of the container.

\n
[2]
\n
c.ii.
\n
\n

Find the time it takes to fill the container to its maximum volume.

\n
[2]
\n
d.
\n
\n

Find the rate of change of the height of the water when the container is filled to half its maximum volume.

\n
[6]
\n
e.
\n
", "Markscheme": "
\n

\n

correct shape (concave down) within the given domain 1x2             A1

\n

1,0 and 2,3=2,1.73             A1

\n

 

\n

Note: The coordinates of endpoints may be seen on the graph or marked on the axes.

\n

 

\n

[2 marks]

\n
a.
\n
\n

interchanging x and y (seen anywhere)             M1

\n

x=y2-1

\n

x2=y2-1             A1

\n

y=x2+1             A1

\n

f-1x=x2+1             AG

\n

 

\n

[3 marks]

\n
b.i.
\n
\n

0x3  OR domain 0,3=0,1.73             A1

\n

1y2  OR  1f-1x2  OR  range 1,2             A1

\n

 

\n

[2 marks]

\n
b.ii.
\n
\n

attempt to substitute x=y2+1 into the correct volume formula             (M1)

\n

V=π0hy2+12dy =π0hy2+1dy             A1

\n

=π13y3+y0h             A1

\n

=π13h3+h             AG

\n


Note:
Award marks as appropriate for correct work using a different variable e.g. π0hx2+12dx

\n


[3 marks]

\n
c.i.
\n
\n

attempt to substitute h=3  =1.732 into V             (M1)

\n

V=10.8828

\n

V=10.9m3  =23πm3             A1

\n

 

\n

[2 marks]

\n
c.ii.
\n
\n

time =10.88280.4=23π0.4             (M1)

\n

=27.207

\n

=27.2=53πs             A1

\n

 

\n

[2 marks]

\n
d.
\n
\n

attempt to find the height of the tank when V=5.4414 =3π             (M1)

\n

π13h3+h=5.4414  =3π

\n

h=1.1818             (A1)

\n

attempt to use the chain rule or differentiate V=π13h3+h with respect to t             (M1)

\n

dhdt=dhdV×dVdt=1πh2+1×dVdt  OR  dVdt=πh2+1dhdt             (A1)

\n

attempt to substitute their h and dVdt=0.4             (M1)

\n

dhdt=0.4π1.18182+1=0.053124

\n

=0.0531m s-1             A1

\n

 

\n

[6 marks]

\n
e.
\n
", "Examiners report": "
\n

Part a) was generally well done, with the most common errors being to use an incorrect domain or not to give the coordinates of the endpoints. Some graphs appeared to be straight lines; some candidates drew sketches which were too small which made it more difficult for them to show the curvature.

\n

Most candidates were able to show the steps to find an inverse function in part b), although occasionally a candidate did not explicitly swop the x and y variables before writing down the inverse function, which was given in the question. Many candidates struggled to identify the domain and range of the inverse, despite having a correct graph.

\n

Part c) required a rotation around the y-axis, but a number of candidates attempted to rotate around the x-axis or failed to include limits. In the same vein, many substituted 2 into the formula instead of the square root of 3 when answering the second part. Many subsequently gained follow through marks on part d).

\n

There were a number of good attempts at related rates in part e), with the majority differentiating V with respect to t, using implicit differentiation. However, many did not find the value of h which corresponded to halving the volume, and a number did not differentiate with respect to t, only with respect to h.

\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "22M.2.AHL.TZ1.10", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-3-graphing", "ahl-2-14-odd-and-even-functions-self-inverse-inverse-and-domain-restriction", "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection", "ahl-5-17-areas-under-curve-onto-y-axis-volume-of-revolution-(about-x-and-y-axes)", "ahl-5-14-implicit-functions-related-rates-optimisation" ] }, { "Question": "
\n

The continuous random variable X has probability density function

\n

fx=k4-3x2,0x1    0,otherwise.

\n
\n

Find the value of k.

\n
[4]
\n
a.
\n
\n

Find E(X).

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

attempt to integrate k4-3x2            (M1)

\n

=k13arcsin32x            A1

\n

Note: Award (M1)A0 for arcsin32x.
Condone absence of k up to this stage.

\n

 

\n

equating their integrand to 1             M1

\n

k13arcsin32x01=1

\n

k=33π            A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

E(X)=33π01x4-3x2dx            A1

\n


Note: Condone absence of limits if seen at a later stage.

\n


EITHER

\n

attempt to integrate by inspection            (M1)

\n

=33π×-16-6x4-3x2-12dx

\n

=33π-134-3x201            A1

\n


Note: Condone the use of k up to this stage.

\n


OR

\n

for example, u=4-3x2dudx=-6x

\n


Note: Other substitutions may be used. For example u=-3x2.

\n

=-32π41u-12du            M1

\n


Note:
Condone absence of limits up to this stage.

\n

=-32π2u41            A1

\n


Note: Condone the use of k up to this stage.

\n


THEN

\n

=3π            A1

\n


Note:
Award A0M1A1A0 for their k-134-3x2 or k-2u for working with incorrect or no limits.

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n

Most candidates who attempted part (a) knew that the integrand must be equated to 1 and only a small proportion of these managed to recognize the standard integral involved here. The effect of 3 in 3x2 was missed by many resulting in very few completely correct answers for this part. Part (b) proved to be challenging for vast majority of the candidates and was poorly done in general. Stronger candidates who made good progress in part (a) were often successful in part (b) as well. Most candidates used a substitution, however many struggled to make progress using this approach. Often when using a substitution, the limits were unchanged. If the function was re-written in terms of x, this did not result in an error in the final answer.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.AHL.TZ1.7", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-10-indefinite-integration-reverse-chain-by-substitution" ] }, { "Question": "
\n

Consider the equation kx2-k+3x+2k+9=0, where k.

\n
\n

Write down an expression for the product of the roots, in terms of k.

\n
[1]
\n
a.
\n
\n

Hence or otherwise, determine the values of k such that the equation has one positive and one negative real root.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

product of roots =2k+9k             A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

recognition that the product of the roots will be negative            (M1)

\n

2k+9k<0

\n

critical values k=0,-92 seen             (A1)

\n

-92<k<0             A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.AHL.TZ1.8", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-7-solutions-of-quadratic-equations-and-inequalities-discriminant-and-nature-of-roots" ] }, { "Question": "
\n

Consider the function fx=2x-12x, x.

\n
\n

The function g is given by gx=x-1x2-2x-3, where x, x-1, x3.

\n
\n

Show that f is an odd function.

\n
[2]
\n
a.
\n
\n

Solve the inequality fxgx.

\n
[4]
\n
b.
\n
", "Markscheme": "
\n

attempt to replace x with -x           M1

\n

f-x=2-x-12-x

\n


EITHER

\n

=12x-2x=-fx           A1

\n


OR

\n

=-2x-12x=-fx           A1

\n


Note:
Award M1A0 for a graphical approach including evidence that either the graph is invariant after rotation by 180° about the origin or the graph is invariant after a reflection in the y-axis and then in the x-axis (or vice versa).

\n

so f is an odd function           AG

\n

 

\n

[2 marks]

\n
a.
\n
\n

attempt to find at least one intersection point            (M1)

\n

x=-1.26686, x=0.177935, x=3.06167

\n

x=-1.27, x=0.178, x=3.06

\n

-1.27x-1,           A1

\n

0.178x<3,           A1

\n

x3.06           A1

\n

 

\n

[4 marks]

\n
b.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.AHL.TZ1.6", "topics": [ "topic-2-functions" ], "subtopics": [ "ahl-2-14-odd-and-even-functions-self-inverse-inverse-and-domain-restriction", "sl-2-10-solving-equations-graphically-and-analytically" ] }, { "Question": "
\n

A survey at a swimming pool is given to one adult in each family. The age of the adult, a years old, and of their eldest child, c years old, are recorded.

\n

The ages of the eldest child are summarized in the following box and whisker diagram.

\n

\n
\n

The regression line of a on c is a=74c+20. The regression line of c on a is c=12a-9.

\n
\n

Find the largest value of c that would not be considered an outlier.

\n
[3]
\n
a.
\n
\n

One of the adults surveyed is 42 years old. Estimate the age of their eldest child.

\n
[2]
\n
b.i.
\n
\n

Find the mean age of all the adults surveyed.

\n
[2]
\n
b.ii.
\n
", "Markscheme": "
\n

IQR=10-6=4             (A1)

\n

attempt to find Q3+1.5×IQR             (M1)

\n

10+6

\n

16             A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

choosing c=12a-9             (M1)

\n

12×42-9

\n

=12 (years old)            A1

\n

 

\n

[2 marks]

\n
b.i.
\n
\n

attempt to solve system by substitution or elimination            (M1)

\n

34 (years old)            A1

\n

 

\n

[2 marks]

\n
b.ii.
\n
", "Examiners report": "
\n

Many candidates correctly found the value of 16. Some then incorrectly went on to state that 15 was therefore the minimum value that was not an outlier. For part (b) students needed to choose the appropriate rule to use to estimate the child's age. It was clear that many did not know there was a choice to be made and used both equations. As the mean point (𝑐̅,𝑎̅ ) lies on both regression lines, in part (c) candidates needed to solve the system of equations to find the mean adult age, 𝑎̅. Few candidates seemed to be aware of this.

\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
", "question_id": "22M.1.SL.TZ1.3", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-1-concepts-reliability-and-sampling-techniques", "sl-4-3-mean-median-mode-mean-of-grouped-data-standard-deviation-quartiles-iqr" ] }, { "Question": "
\n

Consider the functions f(x)=3sinx+cosx where 0xπ and g(x)=2x where x.

\n
\n

Find (fg)(x).

\n
[2]
\n
a.
\n
\n

Solve the equation (fg)(x)=2cos2x where 0xπ.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

(fg)(x)=f2x           (A1)

\n

f2x=3sin2x+cos2x            A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

3sin2x+cos2x=2cos2x

\n

3sin2x=cos2x

\n

recognising to use tan or cot            M1

\n

tan2x=13  OR  cot2x=3 (values may be seen in right triangle)           (A1)

\n

arctan13= π6  (seen anywhere) (accept degrees)           (A1)

\n

2x=π6, 7π6

\n

x=π12, 7π12            A1A1

\n

 

\n

Note: Do not award the final A1 if any additional solutions are seen.
Award A1A0 for correct answers in degrees.
Award A0A0 for correct answers in degrees with additional values.

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n

Determining the composite function was very well done. In part (b) very few candidates showed any recognition that tan (or cot) were required to solve this trigonometric equation. Many saw the 2x and simply employed one of the double angle rules but could not then progress to an answer.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.SL.TZ1.4", "topics": [ "topic-2-functions", "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-2-5-composite-functions-identity-finding-inverse", "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule" ] }, { "Question": "
\n

Consider the curve with equation y=(2x-1)ekx, where x and k.

\n

The tangent to the curve at the point where x=1 is parallel to the line y=5ekx.

\n

Find the value of k.

\n
", "Markscheme": "
\n

evidence of using product rule           (M1)

\n

dydx=2x-1×kekx+2×ekx  =ekx2kx-k+2            A1

\n

correct working for one of (seen anywhere)            A1

\n

dydx at x=1kek+2ek

\n


OR

\n

slope of tangent is 5ek

\n


their dydx at x=1 equals the slope of y=5ekx  =5ek (seen anywhere)           (M1)

\n

kek+2ek=5ek

\n

k=3            A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n

The product rule was well recognised and used with 𝑥=1 properly substituted into this expression. Although the majority of the candidates tried equating the derivative to the slope of the tangent line, the slope of the tangent line was not correctly identified; many candidates incorrectly substituted 𝑥=1 into the tangent equation, thus finding the y-coordinate instead of the slope.

\n
", "question_id": "22M.1.SL.TZ1.5", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-4-tangents-and-normal" ] }, { "Question": "
\n

Consider f(x)=4sinx+2.5 and gx=4sinx-3π2+2.5+q, where x and q>0.

\n

The graph of g is obtained by two transformations of the graph of f.

\n
\n

Describe these two transformations.

\n
[2]
\n
a.
\n
\n

The y-intercept of the graph of g is at (0, r).

\n

Given that g(x)7, find the smallest value of r.

\n
[5]
\n
b.
\n
", "Markscheme": "
\n

translation (shift) by 3π2 to the right/positive horizontal direction         A1

\n

translation (shift) by q upwards/positive vertical direction         A1

\n

 

\n

Note: accept translation by 3π2q

\n

Do not accept ‘move’ for translation/shift.

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

minimum of 4sinx-3π2 is -4  (may be seen in sketch)          (M1)

\n

-4+2.5+q7

\n

q8.5  (accept q=8.5)         A1

\n

substituting x=0 and their q =8.5 to find r          (M1)

\n

r=  4sin-3π2+2.5+8.5

\n

4+2.5+8.5          (A1)

\n

smallest value of r is 15         A1

\n

 

\n

METHOD 2

\n

substituting x=0 to find an expression (for r) in terms of q          (M1)

\n

g0=r=  4sin-3π2+2.5+q

\n

r=  6.5+q         A1

\n

minimum of 4sinx-3π2 is -4          (M1)

\n

-4+2.5+q7

\n

-4+2.5+r-6.57  (accept =)          (A1)

\n

smallest value of r is 15         A1

\n

 

\n

METHOD 3

\n

4sinx-3π2+2.5+q=4cosx+2.5+q         A1

\n

y-intercept of 4cosx+2.5+q is a maximum          (M1)

\n

amplitude of gx is 4          (A1)

\n

attempt to find least maximum          (M1)

\n

r=2×4+7

\n

smallest value of r is 15         A1

\n

 

\n

[5 marks]

\n
b.
\n
", "Examiners report": "
\n

Candidates knew aspects of the transformations performed but some were unable to correctly describe them fully, e.g., omitting direction (right/up/positive) or using 'move' instead of translate/shift. Each description requires three parts: transformation type, size and direction. e.g., translation of q units up. For part (b) few candidates were able to fully navigate the reasoning required in this question. A common error was to evaluate sin-3π2=-1, instead of 1. Those who used sketches to assist in their thinking were typically more successful.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.SL.TZ1.6", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-7-circular-functions-graphs-composites-transformations" ] }, { "Question": "
\n

Consider the differential equation x2dydx=y2-2x2 for x>0 and y>2x. It is given that y=3 when x=1.

\n
\n

Use Euler’s method, with a step length of 0.1, to find an approximate value of y when x=1.5.

\n
[4]
\n
a.
\n
\n

Use the substitution y=vx to show that xdvdx=v2-v-2.

\n
[3]
\n
b.
\n
\n

By solving the differential equation, show that y=8x+x44-x3.

\n
[10]
\n
c.i.
\n
\n

Find the actual value of y when x=1.5.

\n
[1]
\n
c.ii.
\n
\n

Using the graph of y=8x+x44-x3, suggest a reason why the approximation given by Euler’s method in part (a) is not a good estimate to the actual value of y at x=1.5.

\n
[1]
\n
c.iii.
\n
", "Markscheme": "
\n

attempt to use Euler’s method             (M1)

\n

xn+1=xn+0.1;  yn+1=yn+0.1×dydx, where dydx=y2-2x2x2

\n

correct intermediate y-values             (A1)(A1)

\n

3.7,4.63140,5.92098,7.79542

\n

 

\n

Note: A1 for any two correct y-values seen

\n

 

\n

y=10.6958

\n

y=10.7             A1

\n

 

\n

Note: For the final A1, the value 10.7 must be the last value in a table or a list, or be given as a final answer, not just embedded in a table which has further lines.

\n

 

\n

[4 marks]

\n
a.
\n
\n

y=vxdydx=v+xdvdx             (A1)

\n

replacing y with vx and dydx with v+xdvdx             M1

\n

x2dydx=y2-2x2x2v+xdvdx=v2x2-2x2             A1

\n

v+xdvdx=v2-2  (since x>0)

\n

xdvdx=v2-v-2             AG

\n

 

\n

[3 marks]

\n
b.
\n
\n

attempt to separate variables v and x             (M1)

\n

dvv2-v-2=dxx

\n

dvv-2v+1=dxx             (A1)

\n

attempt to express in partial fraction form              M1

\n

1v-2v+1Av-2+Bv+1

\n

1v-2v+1=131v-2-1v+1             A1

\n

131v-2-1v+1dv=dxx

\n

13lnv-2-lnv+1=lnx+c             A1

\n

 

\n

Note: Condone absence of modulus signs throughout.

\n


EITHER

\n

attempt to find c using x=1, y=3, v=3              M1

\n

c=13ln14

\n

13lnv-2-lnv+1=lnx+13ln14

\n

expressing both sides as a single logarithm             (M1)

\n

lnv-2v+1=lnx34

\n


OR

\n

expressing both sides as a single logarithm             (M1)

\n

lnv-2v+1=lnAx3

\n

attempt to find A using x=1, y=3, v=3              M1

\n

A=14

\n


THEN

\n

v-2v+1=14x3  (since x>0)

\n

substitute v=yx  (seen anywhere)              M1

\n

yx-2yx+1=14x3  (since y>2x)

\n

y-2xy+x=14x3

\n

attempt to make y the subject              M1

\n

y-x3y4=2x+x44             A1

\n

y=8x+x44-x3             AG

\n

 

\n

[10 marks]

\n
c.i.
\n
\n

actual value at y1.5=27.3         A1

\n

 

\n

[1 mark]

\n
c.ii.
\n
\n

gradient changes rapidly (during the interval considered)  OR

\n

the curve has a vertical asymptote at x=43 =1.5874            R1

\n

 

\n

[1 mark]

\n
c.iii.
\n
", "Examiners report": "
\n

Most candidates showed evidence of an attempt to use Euler's method in part a), although very few explicitly wrote down the formulae, they used in order to calculate successive y-value. In addition, many seemed to take a step-by-step approach rather than using the recursive capabilities of the graphical display calculator.

\n

There were many good attempts at part b), but not all candidates recognised that this would help them to solve part c).

\n

Part c) was done very well by many candidates, although there were a significant number who failed to recognise the need for partial fractions and could not make further progress. A common error was to integrate without a constant of integration, which meant that the initial condition could not be used. The reasoning given for the estimate being poor was often too vague and did not address the specific nature of the function given clearly enough.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
c.iii.
\n
", "question_id": "22M.2.AHL.TZ1.12", "topics": [ "topic-5-calculus", "topic-1-number-and-algebra" ], "subtopics": [ "ahl-5-18-1st-order-des-euler-method-variables-separable-integrating-factor-homogeneous-de-using-sub-y=vx", "ahl-1-11-partial-fractions", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

The following diagram shows a circle with centre O and radius 5 metres.

\n

Points A and B lie on the circle and AO^B=1.9 radians.

\n

\n
\n

Find the length of the chord [AB].

\n
[3]
\n
a.
\n
\n

Find the area of the shaded sector.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

EITHER

\n

uses the cosine rule           (M1)

\n

AB2=52+52-2×5×5×cos1.9           (A1)

\n


OR

\n

uses right-angled trigonometry           (M1)

\n

AB25sin0.95           (A1)

\n


OR

\n

uses the sine rule           (M1)

\n

α=12π-1.9=0.6207

\n

ABsin1.9=5sin0.6207           (A1)

\n


THEN

\n

AB=8.13415

\n

AB=8.13m           A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

let the shaded area be A

\n


METHOD 1

\n

attempt at finding reflex angle           (M1)

\n

AO^B=2π-1.9 =4.3831

\n

substitution into area formula           (A1)

\n

A=12×52×4.3831  OR  2π-1.92π×π52

\n

=54.7898

\n

=54.8m2           A1

\n

 

\n

METHOD 2

\n

let the area of the circle be AC and the area of the unshaded sector be AU

\n

A=AC-AU           (M1)

\n

A=π×52-12×52×1.9  =78.5398-23.75           (A1)

\n

=54.7898

\n

=54.8m2           A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n

Most students used the cosine rule to correctly find AB in part (a), although many found the arc length instead of the chord.

\n

Part (b) was generally correctly solved. Some candidates found the area of the unshaded region rather than the shaded one.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.SL.TZ2.1", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

The derivative of a function g is given by g'x=3x2+5ex, where x. The graph of g passes through the point (0, 4) . Find g(x).

\n
", "Markscheme": "
\n

METHOD 1

\n

recognises that gx=3x2+5exdx           (M1)

\n

gx=x3+5ex+C           (A1)(A1)

\n


Note: Award A1 for each integrated term.

\n

 

\n

substitutes x=0 and y=4 into their integrated function (must involve +C)           (M1)

\n

4=0+5+CC=-1

\n

gx=x3+5ex-1           A1

\n

 

\n

METHOD 2

\n

attempts to write both sides in the form of a definite integral           (M1)

\n

0xg'tdt=0x3t2+5etdt           (A1)

\n

gx-4=x3+5ex-5e0           (A1)(A1)

\n


Note:
Award A1 for gx-4 and A1 for x3+5ex-5e0.

\n


gx=x3+5ex-1           A1

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n

While many students were successful in solving this question, some did not consider the constant of integration or struggled to integrate the exponential term. A few students lost the final mark for stopping at C=-1 and not giving the formula for g(x).

\n
", "question_id": "22M.2.SL.TZ2.2", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis" ] }, { "Question": "
\n

Gemma and Kaia started working for different companies on January 1st 2011.

\n

Gemma’s starting annual salary was $45000, and her annual salary increases 2% on January 1st each year after 2011.

\n
\n

Kaia’s annual salary is based on a yearly performance review. Her salary for the years 2011, 2013, 2014, 2018, and 2022 is shown in the following table.

\n

\n
\n

Find Gemma’s annual salary for the year 2021, to the nearest dollar.

\n
[3]
\n
a.
\n
\n

Assuming Kaia’s annual salary can be approximately modelled by the equation S=ax+b, show that Kaia had a higher salary than Gemma in the year 2021, according to the model.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

METHOD 1

\n

using geometric sequence with r=1.02           (M1)

\n

correct expression or listing terms correctly           (A1)

\n

45000×1.0210  OR  45000×1.0211-1  OR  listing terms

\n

Gemma’s salary is $54855 (must be to the nearest dollar)           A1

\n

 

\n

METHOD 2

\n

N=10

\n

PV=45000

\n

I%=2

\n

P/Y=1

\n

C/Y=1

\n

FV=±54854.7489           (M1)(A1)

\n

Gemma’s salary is $54855 (must be to the nearest dollar)           A1

\n

 

\n

[3 marks]

\n
a.
\n
\n

finds a=1096.89 and b=-2160753.8 (accept b=-2.16×106)         (A1)(A1)

\n


Note:
Award (A1)(A1) for S=1096.89x+33028.49, or S=1096.89x+43997.4, or S=1096.89x+45094.3

\n


Kaia’s salary in 2021 is $56063.21 (accept $56817.09 from b=-2.16×106)           A1

\n

Kaia had a higher salary than Gemma in 2021           AG

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n

Many errors were seen in part (a). Some candidates used the incorrect formula 1+0.0210010 or used an incorrect value for the exponent e.g. 9 was often seen. Others lost the final mark for not answering to the nearest dollar.
Very few tried to make a table of values.

\n

In part (b) students often let x represent the number of years since a given year, rather than the year itself. Despite this, most were able to find the correct amount with their equation and were awarded marks as appropriate. Some students did not realise regression on GDC was expected and tried to work with a few given data points, others had difficulty dealing with the constant in the regression equation if it was reported using scientific notation.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.SL.TZ2.3", "topics": [ "topic-1-number-and-algebra", "topic-2-functions" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series", "sl-2-1-equations-of-straight-lines-parallel-and-perpendicular" ] }, { "Question": "
\n

Events A and B are independent and P(A)=3P(B).

\n

Given that P(AB)=0.68, find P(B).

\n
", "Markscheme": "
\n

P(AB)=PA+PB-P(AB)=0.68

\n

substitution of PA·PB for P(AB) in P(AB)         (M1)

\n

PA+PB-PAPB  =0.68

\n

substitution of 3P(B) for PA         (M1)

\n

3PB+PB-3PBPB=0.68  (or equivalent)         (A1)

\n

 

\n

Note: The first two M marks are independent of each other.

\n

 

\n

attempts to solve their quadratic equation         (M1)

\n

P(B)=0.2, 1.133 15, 1715

\n

P(B)=0.2 =15          A2

\n

 

\n

Note: Award A1 if both answers are given as final answers for P(B).

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n

This question proved difficult for many students. One common error was to use P(AB)=P(A)+P(B), which simplified the problem greatly, resulting in a linear, not a quadratic equation.

\n
", "question_id": "22M.2.SL.TZ2.4", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

A random sample of nine adults were selected to see whether sleeping well affected their reaction times to a visual stimulus. Each adult’s reaction time was measured twice.

\n

The first measurement for reaction time was taken on a morning after the adult had slept well. The second measurement was taken on a morning after the same adult had not slept well.

\n

The box and whisker diagrams for the reaction times, measured in seconds, are shown below.

\n

\n

Consider the box and whisker diagram representing the reaction times after sleeping well.

\n
\n

State the median reaction time after sleeping well.

\n
[1]
\n
a.
\n
\n

Verify that the measurement of 0.46 seconds is not an outlier.

\n
[3]
\n
b.
\n
\n

State why it appears that the mean reaction time is greater than the median reaction time.

\n
[1]
\n
c.
\n
\n

Now consider the two box and whisker diagrams.

\n

Comment on whether these box and whisker diagrams provide any evidence that might suggest that not sleeping well causes an increase in reaction time.

\n
[1]
\n
d.
\n
", "Markscheme": "
\n

0.28 (s)          A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

IQR=0.35-0.27 =0.08 (s)           (A1)

\n

substituting their IQR into correct expression for upper fence           (A1)

\n

0.35+1.5×0.08 =0.47 (s)  

\n

0.46<0.47         R1

\n

so 0.46 (s) is not an outlier         AG

\n

 

\n

[3 marks]

\n
b.
\n
\n

EITHER

\n

the median is closer to the lower quartile (positively skewed)        R1

\n


OR

\n

The distribution is positively skewed        R1

\n


OR

\n

the range of reaction times below the median is smaller than the range of reaction times above the median        R1

\n

 

\n

Note: These are sample answers from a range of acceptable correct answers. Award R1 for any correct statement that explains this.
Do not award R1 if there is also an incorrect statement, even if another statement in the answer is correct. Accept a correctly and clearly labelled diagram.

\n

 

\n

[1 mark]

\n
c.
\n
\n

EITHER

\n

the distribution for ‘not sleeping well’ is centred at a higher reaction time        R1

\n


OR

\n

The median reaction time after not sleeping well is equal to the upper quartile reaction time after sleeping well      R1

\n


OR

\n

75% of reaction times are <0.35 seconds after sleeping well, compared with 50% after not sleeping well       R1

\n


OR

\n

the sample size of 9 is too small to draw any conclusions       R1

\n

 

\n

Note: These are sample answers from a range of acceptable correct answers. Accept any relevant correct statement that relates to the median and/or quartiles shown in the box plots. Do not accept a comparison of means. Do not award R1 if there is also an incorrect statement, even if another statement in the answer is correct.

\n

Award R0 to “correlation does not imply causation”.

\n

 

\n

[1 mark]

\n
d.
\n
", "Examiners report": "
\n

Parts (a) and (b) were generally known, but answers to parts (c) and (d) showed poor understanding of interpreting data. Many students thought they could find the mean by considering only the end points. Others assumed it would be halfway between the quartiles. When it came to evidence, many were far too quick to say the diagrams 'proved' something. Most compared only the medians and thought that was sufficient evidence, completely ignoring the fact the median only represented one data point. Others just compared the maximum and minimum. A few commented correctly that 9 subjects was too small a sample to prove anything.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "22M.2.SL.TZ2.5", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-2-histograms-cf-graphs-box-plots", "sl-4-1-concepts-reliability-and-sampling-techniques" ] }, { "Question": "
\n

A particle moves in a straight line such that its velocity, vm s-1, at time t seconds is given by v=t2+1cost4, 0t3.

\n
\n

Determine when the particle changes its direction of motion.

\n
[2]
\n
a.
\n
\n

Find the times when the particle’s acceleration is -1.9m s-2.

\n
[3]
\n
b.
\n
\n

Find the particle’s acceleration when its speed is at its greatest.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

recognises the need to find the value of t when v=0           (M1)

\n

t=1.57079 =π2

\n

t=1.57 =π2 (s)             A1

\n

 

\n

[2 marks]

\n
a.
\n
\n

recognises that at=v't             (M1)

\n

t1=2.26277, t2=2.95736

\n

t1=2.26, t2=2.96 (s)             A1A1

\n

 

\n

Note: Award M1A1A0 if the two correct answers are given with additional values outside 0t3.

\n

 

\n

[3 marks]

\n
b.
\n
\n

speed is greatest at t=3              (A1)

\n

a=-1.83778

\n

a=-1.84 m s-2             A1

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n

In part (a) many did not realize the change of motion occurred when v=0. A common error was finding v(0) or thinking that it was at the maximum of v

\n

In part (b), most candidates knew to differentiate but some tried to substitute in -1.9 for t, while others struggled to differentiate the function by hand rather than using the GDC. Many candidates tried to solve the equation analytically and did not use their technology. Of those who did, many had their calculators in degree mode.

\n

Almost all candidates who attempted part (c) thought the greatest speed was the same as the maximum of v.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.2.SL.TZ2.6", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-9-kinematics-problems", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

A farmer is placing posts at points A, B, and C in the ground to mark the boundaries of a triangular piece of land on his property.

\n

From point A, he walks due west 230 metres to point B.
From point B, he walks 175 metres on a bearing of 063° to reach point C.

\n

This is shown in the following diagram.

\n

\n
\n

The farmer wants to divide the piece of land into two sections. He will put a post at point D, which is between A and C. He wants the boundary BD to divide the piece of land such that the sections have equal area. This is shown in the following diagram.

\n

\n
\n

Find the distance from point A to point C.

\n
[4]
\n
a.
\n
\n

Find the area of this piece of land.

\n
[2]
\n
b.
\n
\n

Find CÂB.

\n
[3]
\n
c.
\n
\n

Find the distance from point B to point D.

\n
[5]
\n
d.
\n
", "Markscheme": "
\n

AB^C=27°              (A1)

\n

attempt to substitute into cosine rule              (M1)

\n

1752+2302-2175230cos27°              (A1)

\n

108.62308

\n

AC=109m            A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

correct substitution into area formula             (A1)

\n

12×175×230×sin27°

\n

9136.55

\n

area =9140m2            A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

attempt to substitute into sine rule or cosine rule             (M1)

\n

sin27°108.623=sinA^175  OR  cosA=108.6232+2302-17522×108.623×230             (A1)

\n

47.0049

\n

CÂB=47.0°            A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

METHOD 1

\n

recognizing that for areas to be equal, AD=DC             (M1)

\n

AD=12AC=54.3115            A1

\n

attempt to substitute into cosine rule to find BD             (M1)

\n

correct substitution into cosine rule             (A1)

\n

BD2=2302+54.31152-223054.3115cos47.0049°

\n

BD=197.009

\n

BD=197m            A1

\n

 

\n

METHOD 2

\n

correct expressions for areas of triangle BDA and triangle BCD using BD            A1

\n

12×BD×230×sinx°  and  12×BD×175×sin27-x°  OR

\n

12×BD×230×sin27-x°  and  12×BD×175×sinx°

\n

correct equation in terms of x             (A1)

\n

175sin27-x=230sinx  or  175sinx=230sin27-x

\n

x=11.6326  or  x=15.3673             (A1)

\n

substituting their value of x into equation to solve for BD             (M1)

\n

12×BD×230×sin11.6326=12×BD×175×sin15.3673  or

\n

12×BD×230×sin11.6326=12×9136.55

\n

BD=197m            A1

\n

 

\n

[5 marks]

\n
d.
\n
", "Examiners report": "
\n

Students performed well on parts (a)-(c), correctly applying the cosine rule, the sine formula for area and the sine rule. Part (d) proved challenging. A common error was to falsely assume that segment BD bisected angle ABC.

\n

A significant number of candidates did not have their calculator in degree mode or started in radians and changed to degrees part way through but used answers they had obtained when they were in radian mode. They got answers which were clearly impossible from the diagram, but most did not notice this.

\n

Accuracy was a great problem throughout this question: premature rounding, incorrect rounding, or quoting more figures for the answer than they had used in the calculation.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "22M.2.SL.TZ2.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-2-2d-and-3d-trig-sine-rule-cosine-rule-area" ] }, { "Question": "
\n

A scientist conducted a nine-week experiment on two plants, A and B, of the same species. He wanted to determine the effect of using a new plant fertilizer. Plant A was given fertilizer regularly, while Plant B was not.

\n

The scientist found that the height of Plant A, hA cm, at time t weeks can be modelled by the function hA(t)=sin(2t+6)+9t+27, where 0t9.

\n

The scientist found that the height of Plant B, hB cm, at time t weeks can be modelled by the function hB(t)=8t+32, where 0t9.

\n
\n

Use the scientist’s models to find the initial height of

\n
\n

Plant B.

\n
[1]
\n
a.i.
\n
\n

Plant A correct to three significant figures.

\n
[2]
\n
a.ii.
\n
\n

Find the values of t when hAt=hBt.

\n
[3]
\n
b.
\n
\n

For 0t9, find the total amount of time when the rate of growth of Plant B was greater than the rate of growth of Plant A.

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

32 (cm)          A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

hA0=sin6+27          (M1)

\n

=26.7205

\n

=26.7 (cm)          A1

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

attempts to solve hAt=hBt for t          (M1)

\n

t=4.00746,4.70343,5.88332

\n

t=4.01,4.70,5.88 (weeks)          A2

\n

 

\n

[3 marks]

\n
b.
\n
\n

recognises that hA't and hB't are required          (M1)

\n

attempts to solve hA't=hB't for t          (M1)

\n

t=1.18879 and 2.23598  OR  4.33038 and 5.37758   OR  7.47197 and 8.51917          (A1)

\n

 

\n

Note: Award full marks for t=4π3-3, 5π3-3, 7π3-3, 8π3-3 10π3-3, 11π3-3.

\n

Award subsequent marks for correct use of these exact values.

\n

 

\n

1.18879<t<2.23598  OR  4.33038<t<5.37758  OR

\n

7.47197<t<8.51917          (A1)

\n

attempts to calculate the total amount of time          (M1)

\n

32.2359-1.1887  =35π3-3-4π3-3

\n

=3.14 =π (weeks)          A1

\n

 

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n

Many students did not change their calculators back to radian mode. This meant they had no chance of correctly answering parts (c) and (d), since even if follow through was given, there were not enough intersections on the graphs.

\n

Most managed part (a) and some attempted to equate the functions in part b) but few recognised that 'rate of growth' was the derivatives of the given functions, and of those who did, most were unable to find them.

\n

Almost all the candidates who did solve part (c) gave the answer 3×1.05=3.15, when working with more significant figures would have given them 3.14. They lost the last mark.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.2.SL.TZ2.8", "topics": [ "topic-2-functions", "topic-3-geometry-and-trigonometry", "topic-5-calculus" ], "subtopics": [ "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-3-7-circular-functions-graphs-composites-transformations", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules" ] }, { "Question": "
\n

The time it takes Suzi to drive from home to work each morning is normally distributed with a mean of 35 minutes and a standard deviation of σ minutes.

\n

On 25% of days, it takes Suzi longer than 40 minutes to drive to work.

\n
\n

Suzi will be late to work if it takes her longer than 45 minutes to drive to work. The time it takes to drive to work each day is independent of any other day.

\n

Suzi will work five days next week.

\n
\n

Suzi will work 22 days this month. She will receive a bonus if she is on time at least 20 of those days.

\n

So far this month, she has worked 16 days and been on time 15 of those days.

\n
\n

Find the value of σ.

\n
[4]
\n
a.
\n
\n

On a randomly selected day, find the probability that Suzi’s drive to work will take longer than 45 minutes.

\n
[2]
\n
b.
\n
\n

Find the probability that she will be late to work at least one day next week.

\n
[3]
\n
c.
\n
\n

Given that Suzi will be late to work at least one day next week, find the probability that she will be late less than three times.

\n
[5]
\n
d.
\n
\n

Find the probability that Suzi will receive a bonus.

\n
[4]
\n
e.
\n
", "Markscheme": "
\n

METHOD 1

\n

T~N35,σ2

\n

PT>40=0.25  or  PT<40=0.75          (M1)

\n

attempt to solve for σ graphically or numerically using the GDC          (M1)

\n

graph of normal curve T~N35,σ2 for PT>40 and y=0.25  OR  PT<40 and y=0.75
OR table of values for PT<40 or PT>40

\n

σ=7.413011

\n

σ=7.41 (min)          A2

\n

 

\n

METHOD 2

\n

T~N35,σ2

\n

PT>40=0.25  or  PT<40=0.75          (M1)

\n

z=0.674489          (A1)

\n

valid equation using their z-score (clearly identified as z-score and not a probability)          (M1)

\n

40-35σ=0.674489  OR  5=0.674489σ

\n

7.413011

\n

σ=7.41 (min)          A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

PT>45          (M1)

\n

=0.0886718

\n

=0.0887          A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

recognizing binomial probability            (M1)

\n

L~B5, 0.0886718

\n

PL1=1-PL=0  OR

\n

PL1=PL=1+PL=2+PL=3+PL=4+PL=5            (M1)

\n

0.371400

\n

PL1=0.371            A1

\n

 

\n

[3 marks]

\n
c.
\n
\n

recognizing conditional probability in context            (M1)

\n

finding L<3L1=L=1, L=2   (may be seen in conditional probability)            (A1)

\n

PL=1+PL=2=0.36532  (may be seen in conditional probability)            (A1)

\n

PL<3L1=0.365320.37140            (A1)

\n

0.983636

\n

0.984            A1

\n

 

\n

[5 marks]

\n
d.
\n
\n

METHOD 1

\n

recognizing that Suzi can be late no more than once (in the remaining six days)            (M1)

\n

X~B6, 0.0886718, where X is the number of days late            (A1)

\n

PX1=PX=0+PX=1            (M1)

\n

=0.907294

\n

PSuzi gets a bonus=0.907            A1

\n


Note: The first two marks may be awarded independently.

\n

 

\n

METHOD 2

\n

recognizing that Suzi must be on time at least five times (of the remaining six days)            (M1)

\n

X~B6, 0.911328, where X is the number of days on time           (A1)

\n

PX5=1-PX4  OR  1-0.0927052  OR PX=5+X=6 OR 0.334434+0.572860            (M1)

\n

=0.907294

\n

PSuzi gets a bonus=0.907            A1

\n


Note: The first two marks may be awarded independently.

\n

 

\n

[4 marks]

\n
e.
\n
", "Examiners report": "
\n

In part (a) many candidates did not know to use inverse normal to find a z value. Some did find z, then rounded it to 3 sf and got an incorrect value for sigma.

\n

Part (b) was mostly well done.

\n

In (c) most recognised the binomial and handled 'at least one' correctly.

\n

In (d) many recognised conditional probability, but most candidates were not able to find the intersection of the events as P(1) + P(2).

\n

In part (e), those candidates who did understand what to do often misunderstood that they needed to look at 1 or no more lates and just considered one more late. Something similar happened to those who approached the question by considering the times Suzi was on time. 

\n

This question was only correctly answered by a few, and students tended to perform either very well or very poorly.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "22M.2.SL.TZ2.9", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-12-z-values-inverse-normal-to-find-mean-and-standard-deviation", "sl-4-9-normal-distribution-and-calculations", "sl-4-8-binomial-distribution", "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Consider integers a and b such that a2+b2 is exactly divisible by 4. Prove by contradiction that a and b cannot both be odd.

\n
", "Markscheme": "
\n

Assume that a and b are both odd.             M1

\n


Note: Award M0 for statements such as “let a and b be both odd”.
Note: Subsequent marks after this M1 are independent of this mark and can be awarded.

\n


Then a=2m+1 and b=2n+1            A1

\n

a2+b22m+12+2n+12

\n

=4m2+4m+1+4n2+4n+1            A1

\n

=4m2+m+n2+n+2            (A1)

\n

(4m2+m+n2+n is always divisible by 4) but 2 is not divisible by 4. (or equivalent)            R1

\n

a2+b2 is not divisible by 4, a contradiction. (or equivalent)            R1

\n

hence a and b cannot both be odd.            AG

\n


Note: Award a maximum of M1A0A0(A0)R1R1 for considering identical or two consecutive odd numbers for a and b.

\n

 

\n

[6 marks]

\n
", "Examiners report": "
\n

Most candidates did not present their proof in a formal manner and merely relied on an algebraic approach rendering the proof incomplete. Very few candidates earned the first mark for making a clear assumption that a and b are both odd. A significant number of candidates only considered consecutive or identical odd numbers. The required reasoning to complete the proof were often poorly expressed or missing altogether. Only a small number of candidates were awarded all the available marks for this question.

\n
", "question_id": "22M.1.AHL.TZ1.8", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-15-proof-by-induction-contradiction-counterexamples" ] }, { "Question": "
\n

Consider the complex numbers z1=1+bi and z2=1-b2-2bi, where b, b0.

\n
\n

Find an expression for z1z2 in terms of b.

\n
[3]
\n
a.
\n
\n

Hence, given that argz1z2=π4, find the value of b.

\n
[3]
\n
b.
\n
", "Markscheme": "
\n

z1z2=1+bi1-b2-2bi

\n

=1-b2-2i2b2+i-2b+b-b3             M1

\n

=1+b2+i-b-b3            A1A1

\n


Note: Award A1 for 1+b2 and A1 for -bi-b3i.

\n

 

\n

[3 marks]

\n
a.
\n
\n

argz1z2=arctan-b-b31+b2=π4            (M1)

\n


EITHER
arctan-b=π4 (since 1+b20, for b)            A1

\n


OR

\n

-b-b3=1+b2  (or equivalent)            A1

\n


THEN

\n

b=-1            A1

\n

 

\n

[3 marks]

\n
b.
\n
", "Examiners report": "
\n

Part (a) was generally well done with many completely correct answers seen. Part (b) proved to be challenging with many candidates incorrectly equating the ratio of their imaginary and real parts to π4 instead of tanπ4. Stronger candidates realized that when θ=π4, it forms an isosceles right-angled triangle and equated the real and imaginary parts to obtain the value of b .

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.1.AHL.TZ1.9", "topics": [ "topic-1-number-and-algebra", "topic-3-geometry-and-trigonometry" ], "subtopics": [ "ahl-1-12-complex-numbers-cartesian-form-and-argand-diag", "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule" ] }, { "Question": "
\n

The following diagram shows the curve x236+y-4216=1, where hy4.

\n

\n

The curve from point Q to point B is rotated 360° about the y-axis to form the interior surface of a bowl. The rectangle OPQR, of height hcm, is rotated 360° about the y-axis to form a solid base.

\n

The bowl is assumed to have negligible thickness.

\n

Given that the interior volume of the bowl is to be 285cm3, determine the height of the base.

\n
", "Markscheme": "
\n

attempts to express x2 in terms of y         (M1)

\n

V=πh4361-y-4216dy          A1

\n


Note: Correct limits are required.

\n

 

\n

Attempts to solve πh4361-y-4216dy=285 for h         (M1)

\n

Note: Award M1 for attempting to solve 36πh348-h24+83=285 or equivalent for h.

\n


h=0.7926

\n

h=0.793 (cm)          A2

\n

 

\n

[5 marks]

\n
", "Examiners report": "
\n

This question was a struggle for many candidates. To start with, many candidates had difficulty understanding the diagram. Some candidates tried to include the base in their equation. 

\n

Because of this confusion, the question was poorly attempted. Some only received one mark for rearranging the equation to make x2 the subject but were unable to set the correct definite integral with correct terminals. Again, many candidates tried to solve by hand instead of using their GDC. The correct answer was not seen that often.

\n

Those candidates who recognised that the volume was around the y -axis and used their GDC to solve, usually achieved full marks for this question.

\n
", "question_id": "22M.2.AHL.TZ2.6", "topics": [ "topic-5-calculus" ], "subtopics": [ "ahl-5-17-areas-under-curve-onto-y-axis-volume-of-revolution-(about-x-and-y-axes)" ] }, { "Question": "
\n

Consider the series lnx+plnx+13lnx+, where x, x>1 and p, p0.

\n
\n

Consider the case where the series is geometric.

\n
\n

Now consider the case where the series is arithmetic with common difference d.

\n
\n

Show that p=±13.

\n
[2]
\n
a.i.
\n
\n

Hence or otherwise, show that the series is convergent.

\n
[1]
\n
a.ii.
\n
\n

Given that p>0 and S=3+3, find the value of x.

\n
[3]
\n
a.iii.
\n
\n

Show that p=23.

\n
[3]
\n
b.i.
\n
\n

Write down d in the form klnx, where k.

\n
[1]
\n
b.ii.
\n
\n

The sum of the first n terms of the series is ln1x3.

\n

Find the value of n.

\n
[8]
\n
b.iii.
\n
", "Markscheme": "
\n

EITHER

\n

attempt to use a ratio from consecutive terms        M1

\n

plnxlnx=13lnxplnx  OR  13lnx=lnxr2  OR  plnx=lnx13p

\n

 

\n

Note: Candidates may use lnx1+lnxp+lnx13+ and consider the powers of x in geometric sequence

\n

Award M1 for p1=13p.

\n


OR

\n

r=p  and  r2=13        M1

\n


THEN

\n

p2=13  OR  r=±13          A1

\n

p=±13          AG

\n

 

\n

Note: Award M0A0 for r2=13 or p2=13 with no other working seen.

\n

 

\n

[2 marks]

\n
a.i.
\n
\n

EITHER

\n

since, p=13 and 13<1          R1

\n


OR

\n

since, p=13 and -1<p<1          R1

\n


THEN

\n

 the geometric series converges.          AG

\n


Note: Accept r instead of p.
Award R0 if both values of p not considered.

\n

 

\n

[1 mark]

\n
a.ii.
\n
\n

lnx1-13  =3+3           (A1)

\n

lnx=3-33+3-33  OR  lnx=3-3+3-1  lnx=2          A1

\n

x=e2          A1

\n

 

\n

[3 marks]

\n
a.iii.
\n
\n

METHOD 1

\n

attempt to find a difference from consecutive terms or from u2          M1

\n

correct equation          A1

\n

plnx-lnx=13lnx-plnx  OR  13lnx=lnx+2plnx-lnx

\n


Note:
Candidates may use lnx1+lnxp+lnx13+ and consider the powers of x in arithmetic sequence.

\n

Award M1A1 for p-1=13-p

\n

 

\n

2plnx=43lnx  2p=43          A1

\n

p=23          AG

\n

 

\n

METHOD 2

\n

attempt to use arithmetic mean u2=u1+u32          M1

\n

plnx=lnx+13lnx2          A1

\n

2plnx=43lnx  2p=43          A1

\n

p=23          AG

\n

 

\n

METHOD 3

\n

attempt to find difference using u3          M1

\n

13lnx=lnx+2d  d=-13lnx

\n

 

\n

u2=lnx+1213lnx-lnx  OR  plnx-lnx=-13lnx          A1

\n

plnx=23lnx          A1

\n

p=23          AG

\n

 

\n

[3 marks]

\n
b.i.
\n
\n

d=-13lnx       A1

\n

 

\n

[1 mark]

\n
b.ii.
\n
\n

METHOD 1

\n

Sn=n22lnx+n-1×-13lnx

\n

attempt to substitute into Sn and equate to ln1x3           (M1)

\n

n22lnx+n-1×-13lnx=ln1x3

\n

ln1x3=-lnx3=lnx-3           (A1)

\n

=-3lnx           (A1)

\n

correct working with Sn (seen anywhere)           (A1)

\n

n22lnx-n3lnx+13lnx  OR  nlnx-nn-16lnx  OR  n2lnx+4-n3lnx

\n

correct equation without lnx          A1

\n

n273-n3=-3  OR  n-nn-16=-3 or equivalent

\n


Note:
Award as above if the series 1+p+13+ is considered leading to n273-n3=-3.

\n


attempt to form a quadratic =0           (M1)

\n

n2-7n-18=0

\n

attempt to solve their quadratic           (M1)

\n

n-9n+2=0

\n

n=9          A1

\n

 

\n

METHOD 2

\n

ln1x3=-lnx3=lnx-3           (A1)

\n

=-3lnx           (A1)

\n

listing the first 7 terms of the sequence           (A1)

\n

lnx+23lnx+13lnx+0-13lnx-23lnx-lnx+

\n

recognizing first 7 terms sum to 0           M1

\n

8th term is -43lnx           (A1)

\n

9th term is -53lnx           (A1)

\n

sum of 8th and 9th term =-3lnx           (A1)

\n

n=9          A1

\n

 

\n

[8 marks]

\n
b.iii.
\n
", "Examiners report": "
\n

Part (a)(i) was well done with few candidates incorrectly using the value of p to verify rather than to 'show' the given result. In part (a)(ii) most did not consider both values of r and some did know the condition for convergence of a geometric series. Part (a)(iii) was generally well done but some had difficulty in simplifying the surd. Part (b) (i) and (ii) was generally well done. Although many completely correct answers to part b (iii) were noted, weaker candidates often made errors in properties of logarithms or algebraic manipulation leading to an incorrect quadratic equation.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
a.iii.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
b.iii.
\n
", "question_id": "22M.1.AHL.TZ1.10", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "sl-1-3-geometric-sequences-and-series", "sl-1-2-arithmetic-sequences-and-series" ] }, { "Question": "
\n

Consider limx0arctancosx-kx2, where k.

\n
\n

Show that a finite limit only exists for k=π4.

\n
[2]
\n
a.
\n
\n

Using l’Hôpital’s rule, show algebraically that the value of the limit is -14.

\n
[6]
\n
b.
\n
", "Markscheme": "
\n

(as limx0x2=0, the indeterminate form 00 is required for the limit to exist)

\n

limx0arctancosx-k=0        M1

\n

arctan1-k=0  k=arctan1          A1

\n

so k=π4          AG

\n


Note:
Award M1A0 for using k=π4 to show the limit is 00.

\n

 

\n

[2 marks]

\n
a.
\n
\n

limx0arctancosx-π4x2=00

\n

=limx0-sinx1+cos2x2x          A1A1

\n


Note: Award A1 for a correct numerator and A1 for a correct denominator.

\n


recognises to apply l’Hôpital’s rule again          (M1)

\n

=limx0-sinx1+cos2x2x =00

\n


Note:
Award M0 if their limit is not the indeterminate form 00.

\n


EITHER

\n

=limx0-cosx1+cos2x-2sin2xcosx1+cos2x22           A1A1

\n


Note:
Award A1 for a correct first term in the numerator and A1 for a correct second term in the numerator.

\n


OR

\n

limx0-cosx21+cos2x-4xsinxcosx           A1A1

\n


Note:
Award A1 for a correct numerator and A1 for a correct denominator.

\n


THEN

\n

substitutes x=0 into the correct expression to evaluate the limit          A1

\n


Note:
The final A1 is dependent on all previous marks.

\n


=-14          AG

\n

 

\n

[6 marks]

\n
b.
\n
", "Examiners report": "
\n

Part (a) Many candidates recognised the indeterminate form and provided a nice algebraic proof. Some verified by substituting the given value. Therefore, there is a need to teach the candidates the difference between proof and verification. Only a few candidates were able to give a complete 'show that' proof.

\n

Part (b) Many candidates realised that they needed to apply the L'Hôpital's rule twice. There were many mistakes in differentiation using the chain rule. Not all candidates clearly showed the final substitution.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.AHL.TZ2.7", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-5-unit-circle-definitions-of-sin-cos-tan-exact-trig-ratios-ambiguous-case-of-sine-rule" ] }, { "Question": "
\n

Rachel and Sophia are competing in a javelin-throwing competition.

\n

The distances, R metres, thrown by Rachel can be modelled by a normal distribution with mean 56.5 and standard deviation 3.

\n

The distances, S metres, thrown by Sophia can be modelled by a normal distribution with mean 57.5 and standard deviation 1.8.

\n

In the first round of competition, each competitor must have five throws. To qualify for the next round of competition, a competitor must record at least one throw of 60 metres or greater in the first round.

\n

Find the probability that only one of Rachel or Sophia qualifies for the next round of competition.

\n
", "Markscheme": "
\n

Rachel: R~N56.5,32

\n

PR60=0.1216          (A1)

\n

Sophia: S~N57.5,1.82

\n

PS60=0.0824          (A1)

\n

recognises binomial distribution with n=5          (M1)

\n

let NR represent the number of Rachel’s throws that are longer than 60 metres

\n

NR~B5,0.1216

\n

either PNR1=0.4772  or  PNR=0=0.5227          (A1)

\n

let NS represent the number of Sophia’s throws that are longer than 60 metres

\n

NS~B5,0.0824

\n

either PNS1=0.3495  or  PNS=0=0.6504          (A1)

\n


EITHER

\n

uses PNR1PNS=0+PNS1PNR=0          (M1)

\n

Pone of Rachel or Sophia qualify=0.4772×0.6504+0.3495×0.5227

\n


OR

\n

uses PNR1+PNS1-2×PNR1×PNS1          (M1)

\n

Pone of Rachel or Sophia qualify=0.4772+0.3495-2×0.4772×0.3495

\n

 

\n

THEN

\n

=0.4931

\n

 =0.493        A1

\n


Note:
M marks are not dependent on the previous A marks.

\n

 

\n

[7 marks]

\n
", "Examiners report": "
\n

In general, well answered with many candidates getting full marks. On the other end of the spectrum, some candidates could only get the first two marks for normal distribution without recognising the binomial distribution and often just stopping there. Some candidates lost the last two marks for not being able to combine the probabilities correctly.

\n
", "question_id": "22M.2.AHL.TZ2.8", "topics": [ "topic-4-statistics-and-probability" ], "subtopics": [ "sl-4-6-combined-mutually-exclusive-conditional-independence-prob-diagrams" ] }, { "Question": "
\n

Consider the set of six-digit positive integers that can be formed from the digits 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9.

\n

Find the total number of six-digit positive integers that can be formed such that

\n
\n

the digits are distinct.

\n
[2]
\n
a.
\n
\n

the digits are distinct and are in increasing order.

\n
[2]
\n
b.
\n
", "Markscheme": "
\n

9×9×8×7×6×5 =9×P59          (M1)

\n

=136080 =9×9!4!           A1

\n


Note:
Award M1A0 for 10×9×8×7×6×5 =P610=151200=10!4!.

\n

Note: Award M1A0 for P69=60480

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

EITHER

\n

every unordered subset of 6 digits from the set of 9 non-zero digits can be arranged in exactly one way into a 6-digit number with the digits in increasing order.           A1

\n


OR

\n

C69×1           A1

\n


THEN

\n

=84           A1

\n

 

\n

METHOD 2

\n

EITHER

\n

removes 3 digits from the set of 9 non-zero digits and these 6 remaining digits can be arranged in exactly one way into a 6-digit number with the digits in increasing order.           A1

\n


OR

\n

C39×1             A1

\n

 

\n

THEN

\n

=84           A1

\n

 

\n

[2 marks]

\n
b.
\n
", "Examiners report": "
\n

Part (a) A number of candidates got the correct answer here with the valid approach and recognising that zero could not occupy the first position. Some lost a mark by including zero. Many candidates used an incorrect method with combinations or simplified permutations.

\n

Part (b) Only very few candidates got the correct answer. Many left it blank or provided unreasonably enormous numbers as their answers.

\n

Some candidates had the answer to part (b) showing in part (a).

\n

A small number of candidates tried to list all possibilities but mostly unsuccessfully.

\n
a.
\n
\n[N/A]\n
b.
\n
", "question_id": "22M.2.AHL.TZ2.9", "topics": [ "topic-1-number-and-algebra" ], "subtopics": [ "ahl-1-10-perms-and-combs-binomial-with-negative-and-fractional-indices" ] }, { "Question": "
\n

Consider the three planes

\n

1: 2x-y+z=4

\n

2: x-2y+3z=5

\n

3:-9x+3y-2z=32

\n
\n

Show that the three planes do not intersect.

\n
[4]
\n
a.
\n
\n

Verify that the point P(1, -2, 0) lies on both 1 and 2.

\n
[1]
\n
b.i.
\n
\n

Find a vector equation of L, the line of intersection of 1 and 2.

\n
[4]
\n
b.ii.
\n
\n

Find the distance between L and 3.

\n
[6]
\n
c.
\n
", "Markscheme": "
\n

METHOD 1

\n

attempt to eliminate a variable                 M1

\n

obtain a pair of equations in two variables

\n


EITHER

\n

-3x+z=-3 and          A1

\n

-3x+z=44          A1

\n


OR

\n

-5x+y=-7 and          A1

\n

-5x+y=40          A1

\n


OR

\n

3x-z=3 and          A1

\n

3x-z=-795          A1

\n


THEN

\n

the two lines are parallel (-344 or -740 or 3-795)          R1

\n

 

\n

Note: There are other possible pairs of equations in two variables.
To obtain the final R1, at least the initial M1 must have been awarded.

\n

 

\n

hence the three planes do not intersect          AG

\n

 

\n

METHOD 2

\n

vector product of the two normals =-1-5-3  (or equivalent)          A1

\n

r=1-20+λ153  (or equivalent)          A1

\n

 

\n

Note: Award A0 if “r=” is missing. Subsequent marks may still be awarded.

\n

 

\n

Attempt to substitute 1+λ,-2+5λ,3λ in 3                 M1

\n

-91+λ+3-2+5λ-23λ=32

\n

-15=32, a contradiction          R1

\n

hence the three planes do not intersect          AG

\n

 

\n

METHOD 3

\n

attempt to eliminate a variable                M1

\n

-3y+5z=6          A1

\n

-3y+5z=100          A1

\n

0=94, a contradiction           R1

\n

 

\n

Note: Accept other equivalent alternatives. Accept other valid methods.
To obtain the final R1, at least the initial M1 must have been awarded.

\n

 

\n

hence the three planes do not intersect          AG

\n

 

\n

[4 marks]

\n
a.
\n
\n

1:2+2+0=4  and  2:1+4+0=5          A1

\n

 

\n

[1 mark]

\n
b.i.
\n
\n

METHOD 1

\n

attempt to find the vector product of the two normals          M1

\n

2-11×1-23

\n

=-1-5-3          A1

\n

r=1-20+λ153          A1A1

\n

 

\n

Note: Award A1A0 if “r=” is missing.
Accept any multiple of the direction vector.
Working for (b)(ii) may be seen in part (a) Method 2. In this case penalize lack of “r=” only once.

\n

 

\n

METHOD 2

\n

attempt to eliminate a variable from 1 and 2          M1

\n

3x-z=3  OR  3y-5z=-6  OR  5x-y=7

\n

Let x=t

\n

substituting x=t in 3x-z=3 to obtain

\n

z=-3+3t  and  y=5t-7 (for all three variables in parametric form)          A1

\n

r=0-7-3+λ153          A1A1

\n

 

\n

Note: Award A1A0 if “r=” is missing.
Accept any multiple of the direction vector. Accept other position vectors which satisfy both the planes 1 and 2 .

\n

 

\n

[4 marks]

\n
b.ii.
\n
\n

METHOD 1

\n

the line connecting L and 3 is given by L1

\n

attempt to substitute position and direction vector to form L1           (M1)

\n

s=1-20+t-93-2          A1

\n

substitute 1-9t,-2+3t,-2t in 3             M1

\n

-91-9t+3-2+3t-2-2t=32

\n

94t=47t=12          A1

\n

attempt to find distance between 1,-2,0 and their point -72,-12,-1           (M1)

\n

=1-20+12-93-2-1-20=12-92+32+-22

\n

=942          A1

\n

 

\n

METHOD 2

\n

unit normal vector equation of 3 is given by -932·xyz81+9+4           (M1)

\n

=3294          A1

\n

let 4 be the plane parallel to 3 and passing through P
then the normal vector equation of 4 is given by

\n

-932·xyz=-932·1-20=-15             M1

\n

 

\n

unit normal vector equation of 4 is given by

\n

-932·xyz81+9+4=-1594          A1

\n

distance between the planes is 3294--1594           (M1)

\n

=4794=942          A1

\n

 

\n

[6 marks]

\n
c.
\n
", "Examiners report": "
\n

Part (a) was well attempted using a variety of approaches. Most candidates were able to gain marks for part (a) through attempts to eliminate a variable with many subsequently making algebraic errors. Part (b)(i) was well done. For part (b)(ii) few successful attempts were noted, many candidates failed to use an appropriate notation \"r =\" while giving the vector equation of a line. Part (c) proved to be challenging for most candidates with very few correct answers seen. Many candidates did not attempt part (c).

\n
a.
\n
\n[N/A]\n
b.i.
\n
\n[N/A]\n
b.ii.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.1.AHL.TZ1.11", "topics": [ "topic-3-geometry-and-trigonometry" ], "subtopics": [ "sl-3-1-3d-space-volume-angles-distance-midpoints" ] }, { "Question": "
\n

A scientist conducted a nine-week experiment on two plants, A and B, of the same species. He wanted to determine the effect of using a new plant fertilizer. Plant A was given fertilizer regularly, while Plant B was not.

\n

The scientist found that the height of Plant A, hA cm, at time t weeks can be modelled by the function hA(t)=sin(2t+6)+9t+27, where 0t9.

\n

The scientist found that the height of Plant B, hB cm, at time t weeks can be modelled by the function hB(t)=8t+32, where 0t9.

\n
\n

Use the scientist’s models to find the initial height of

\n
\n

Plant B.

\n
[1]
\n
a.i.
\n
\n

Plant A correct to three significant figures.

\n
[2]
\n
a.ii.
\n
\n

Find the values of t when hAt=hBt.

\n
[3]
\n
b.
\n
\n

For t>6, prove that Plant A was always taller than Plant B.

\n
[3]
\n
c.
\n
\n

For 0t9, find the total amount of time when the rate of growth of Plant B was greater than the rate of growth of Plant A.

\n
[6]
\n
d.
\n
", "Markscheme": "
\n

32 (cm)          A1

\n

 

\n

[1 mark]

\n
a.i.
\n
\n

hA0=sin6+27          (M1)

\n

=26.7205

\n

=26.7 (cm)          A1

\n

 

\n

[2 marks]

\n
a.ii.
\n
\n

attempts to solve hAt=hBt for t          (M1)

\n

t=4.0074,4.7034,5.88332

\n

t=4.01,4.70,5.88 (weeks)          A2

\n

 

\n

[3 marks]

\n
b.
\n
\n

hAt-hBt=sin2t+6+t-5          A1

\n


EITHER

\n

for t>6, t-5>1          A1

\n

and as sin2t+6-1hAt-hBt>0          R1

\n


OR

\n

the minimum value of sin2t+6=-1          R1

\n

so for t>6, hAt-hBt=t-6>0          A1

\n


THEN

\n

hence for t>6, Plant A was always taller than Plant B          AG

\n

 

\n

[3 marks]

\n
c.
\n
\n

recognises that hA't and hB't are required          (M1)

\n

attempts to solve hA't=hB't for t          (M1)

\n

t=1.18879 and 2.23598  OR  4.33038 and 5.37758   OR  7.47197 and 8.51917          (A1)

\n

 

\n

Note: Award full marks for t=4π3-3, 5π3-3, 7π3-3, 8π3-3 10π3-3, 11π3-3.

\n

Award subsequent marks for correct use of these exact values.

\n

 

\n

1.18879<t<2.23598  OR  4.33038<t<5.37758  OR 7.47197<t<8.51917          (A1)

\n

attempts to calculate the total amount of time          (M1)

\n

32.2359-1.1887  =35π3-3-4π3-3

\n

=3.14 =π (weeks)          A1

\n

 

\n

[6 marks]

\n
d.
\n
", "Examiners report": "
\n

Part (a) In general, very well done, most students scored full marks. Some though had an incorrect answer for part(a)(ii) because they had their GDC in degrees.

\n

Part (b) Well attempted. Some accuracy errors and not all candidates listed all three values.

\n

Part (c) Most students tried a graphical approach (but this would only get them one out of three marks) and only some provided a convincing algebraic justification. Many candidates tried to explain in words without a convincing mathematical justification or used numerical calculations with specific time values. Some arrived at the correct simplified equation for the difference in heights but could not do much with it. Then only a few provided a correct mathematical proof.

\n

Part (d) In general, well attempted by many candidates. The common error was giving the answer as 3.15 due to the pre-mature rounding. Some candidates only provided the values of time when the rates are equal, some intervals rather than the total time.

\n
a.i.
\n
\n[N/A]\n
a.ii.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
", "question_id": "22M.2.AHL.TZ2.10", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection", "sl-2-4-key-features-of-graphs-intersections-using-technology", "sl-5-1-introduction-of-differential-calculus", "ahl-2-15-solutions-of-inequalities" ] }, { "Question": "
\n

The function f is defined by f(x)=exsinx, where x.

\n
\n

The function g is defined by g(x)=excosx, where x.

\n
\n

Find the Maclaurin series for f(x) up to and including the x3 term.

\n
[4]
\n
a.
\n
\n

Hence, find an approximate value for 01ex2sinx2dx.

\n
[4]
\n
b.
\n
\n

Show that g(x) satisfies the equation g''(x)=2(g'(x)-g(x)).

\n
[4]
\n
c.i.
\n
\n

Hence, deduce that g4x=2g'''x-g''x.

\n
[1]
\n
c.ii.
\n
\n

Using the result from part (c), find the Maclaurin series for g(x) up to and including the x4 term.

\n
[5]
\n
d.
\n
\n

Hence, or otherwise, determine the value of limx0excosx-1-xx3.

\n
[3]
\n
e.
\n
", "Markscheme": "
\n

METHOD 1

\n

recognition of both known series          (M1)

\n

ex=1+x1!+x22!+  and sinx=x-x33!+x55!+

\n

attempt to multiply the two series up to and including x3 term           (M1)

\n

exsinx=1+x1!+x22!+x-x33!+x55!+

\n

=x-x33!+x2+x32!+           (A1)

\n

exsinx=x+x2+13x3+          A1

\n

 

\n

METHOD 2

\n

fx=exsinx

\n

f'x=excosx+exsinx          A1

\n

f''x=excosx-exsinx+exsinx+excosx =2excosx

\n

f'''x=2excosx-2exsinx

\n

f''x=2excosx  and  f'''x=2excosx-sinx          A1

\n

substitute x=0 into f or its derivatives to obtain Maclaurin series           (M1)

\n

exsinx=0+x1!×1+x22!×2+x33!×2+

\n

exsinx=x+x2+13x3+          A1

\n

 

\n

[4 marks]

\n
a.
\n
\n

ex2sinx2=x2+x4+13x6+           (A1)

\n

substituting their expression and attempt to integrate              M1

\n

01ex2sinx2dx01x2+x4+13x6dx

\n

 

\n

Note: Condone absence of limits up to this stage.

\n

 

\n

=x33+x55+x72101          A1

\n

=61105          A1

\n

 

\n

[4 marks]

\n
b.
\n
\n

attempt to use product rule at least once             M1

\n

g'(x)=excosx-exsinx          A1

\n

g''(x)=excosx-exsinx-exsinx-excosx=-2exsinx          A1

\n


EITHER

\n

2g'(x)-gx=2excosx-exsinx-excosx=-2exsinx          A1

\n


OR

\n

g''(x)=2excosx-exsinx-excosx          A1

\n


THEN

\n

g''(x)=2g'(x)-gx          AG

\n

 

\n

Note: Accept working with each side separately to obtain -2exsinx.

\n

 

\n

[4 marks]

\n
c.i.
\n
\n

g'''(x)=2g''(x)-g'x          A1

\n

g4x=2g'''x-g''x          AG

\n

 

\n

Note: Accept working with each side separately to obtain -4excosx.

\n

 

\n

[1 mark]

\n
c.ii.
\n
\n

attempt to substitute x=0 into a derivative          (M1)

\n

g0=1, g'0=1, g''0=0          A1

\n

g'''0=-2, g40=-4           (A1)

\n

attempt to substitute into Maclaurin formula          (M1)

\n

gx=1+x-23!x3-44!x4+=1+x-13x3-16x4+          A1

\n

 

\n

Note: Do not award any marks for approaches that do not use the part (c) result.

\n

 

\n

[5 marks]

\n
d.
\n
\n

METHOD 1

\n

limx0excosx-1-xx3=limx01+x-13x3-16x4+-1-xx3         M1

\n

=limx0-13-16x+           (A1)

\n

=-13          A1

\n

 

\n

Note: Condone the omission of + in their working.

\n

 

\n

METHOD 2

\n

limx0excosx-1-xx3=00 indeterminate form, attempt to apply l'Hôpital's rule         M1

\n

=limx0excosx-exsinx-13x2=limx0g'x-13x2

\n

=00, using l'Hôpital's rule again

\n

=limx0-2exsinx6x=limx0g''x6x

\n

=00, using l'Hôpital's rule again

\n

=limx0-2exsinx-2excosx6=limx0g'''x6          A1

\n

=-13          A1

\n

 

\n

[3 marks]

\n
e.
\n
", "Examiners report": "
\n

Part (a) was well answered using both methods. A number failed to see the connection between parts (a) and (b). Far too often, a candidate could not add three fractions together in part (b). There were many good responses to part (c) with candidates showing results on both sides are equal. A number of candidates failed to use the result from (c) in part (d). There were some good responses to part (e), with candidates working successfully with the series from (d) or applying l'Hôpital's rule. In particular, some responses were missing the appropriate limit notation and candidates following method 2 did not always show that the initial expression was of an indeterminate form before applying l'Hôpital's rule. Many candidates did not attempt parts (d) and (e).

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.i.
\n
\n[N/A]\n
c.ii.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
", "question_id": "22M.1.AHL.TZ1.12", "topics": [ "topic-5-calculus" ], "subtopics": [ "sl-5-5-integration-introduction-areas-between-curve-and-x-axis", "sl-5-7-the-second-derivative", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "ahl-5-19-maclaurin-series", "ahl-5-13-limits-and-lhopitals" ] }, { "Question": "
\n

The following table shows values of f(x) and g(x) for different values of x.

\n

Both f and g are one-to-one functions.

\n

\n
\n

Find g(0).

\n
[1]
\n
a.
\n
\n

Find (fg)(0).

\n
[2]
\n
b.
\n
\n

Find the value of x such that f(x)=0.

\n
[2]
\n
c.
\n
", "Markscheme": "
\n

g(0)=-2         A1

\n

 

\n

[1 mark]

\n
a.
\n
\n

evidence of using composite function         (M1)

\n

 fg0  OR  f-2

\n

(fg)(0)=8         A1

\n

 

\n

[2 marks]

\n
b.
\n
\n

x=3          A2

\n

 

\n

[2 marks]

\n
c.
\n
", "Examiners report": "
\n

This question was completed successfully by most of the candidates. In part (b) of the question, a few candidates did not recognize the notation for a composite function and instead incorrectly thought they were supposed to multiply values for f(0) and g(0).

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "22M.1.SL.TZ2.1", "topics": [ "topic-2-functions" ], "subtopics": [ "sl-2-2-functions-notation-domain-range-and-inverse-as-reflection", "sl-2-5-composite-functions-identity-finding-inverse" ] }, { "Question": "
\n

Two airplanes, A and B, have position vectors with respect to an origin O given respectively by

\n

rA=19-11+t-624

\n

rB=1012+t42-2

\n

where t represents the time in minutes and 0t2.5.

\n

Entries in each column vector give the displacement east of O, the displacement north of O and the distance above sea level, all measured in kilometres.

\n
\n

The two airplanes’ lines of flight cross at point P.

\n
\n

Find the three-figure bearing on which airplane B is travelling.

\n
[2]
\n
a.
\n
\n

Show that airplane A travels at a greater speed than airplane B.

\n
[2]
\n
b.
\n
\n

Find the acute angle between the two airplanes’ lines of flight. Give your answer in degrees.

\n
[4]
\n
c.
\n
\n

Find the coordinates of P.

\n
[5]
\n
d.i.
\n
\n

Determine the length of time between the first airplane arriving at P and the second airplane arriving at P.

\n
[2]
\n
d.ii.
\n
\n

Let D(t) represent the distance between airplane A and airplane B for 0t2.5.

\n

Find the minimum value of D(t).

\n
[5]
\n
e.
\n
", "Markscheme": "
\n

let ϕ be the required angle (bearing)

\n


EITHER

\n

ϕ=90°-arctan12 =arctan2          (M1)

\n


Note: Award M1 for a labelled sketch.

\n


OR

\n

cosϕ=01·421×20 =0.4472,=15          (M1)

\n

ϕ=arccos0.4472

\n


THEN

\n

063°          A1

\n


Note: Do not accept 063.6° or 63.4° or 1.10c.

\n

 

\n

[2 marks]

\n
a.
\n
\n

METHOD 1

\n

let bA be the speed of A and let bB be the speed of B

\n

attempts to find the speed of one of A or B          (M1)

\n

bA=-62+22+42  or  bB=42+22+-22

\n


Note: Award M0 for bA=192+-12+12 and bB=12+02+122.

\n


bA=7.48 =56 (km min-1) and bB=4.89 =24 (km min-1)          A1

\n

bA>bB so A travels at a greater speed than B          AG

\n

 

\n

METHOD 2

\n

attempts to use speed=distancetime

\n

speedA=rAt2-rAt1t2-t1  and  speedB=rBt2-rBt1t2-t1          (M1)

\n

for example:

\n

speedA=rA1-rA01  and speedB=rB1-rB01

\n

speedA=-62+22+421  and speedB=42+22+221

\n

speedA=7.48214  and speedB=4.8924          A1

\n

speedA>speedB so A travels at a greater speed than B          AG

\n

 

\n

[2 marks]

\n
b.
\n
\n

attempts to use the angle between two direction vectors formula         (M1)

\n

cosθ=-64+22+4-2-62+22+4242+22+-22         (A1)

\n

cosθ=-0.7637 =-784  or  θ=arccos-0.7637 =2.4399

\n

attempts to find the acute angle 180°-θ using their value of θ         (M1)

\n

=40.2°         A1

\n

 

\n

[4 marks]

\n
c.
\n
\n

for example, sets rAt1=rBt2 and forms at least two equations         (M1)

\n

19-6t1=1+4t2

\n

-1+2t1=2t2

\n

1+4t1=12-2t2

\n


Note: Award M0 for equations involving t only.

\n


EITHER

\n

attempts to solve the system of equations for one of t1 or t2         (M1)

\n

t1=2  or  t2=32         A1

\n


OR

\n

attempts to solve the system of equations for t1 and t2         (M1)

\n

t1=2  or  t2=32         A1

\n


THEN

\n

substitutes their t1 or t2 value into the corresponding rA or rB         (M1)

\n

P7,3,9         A1

\n


Note: Accept OP=739. Accept 7 km east of O3 km north of O and 9 km above sea level.

\n

 

\n

[5 marks]

\n
d.i.
\n
\n

attempts to find the value of t1-t2           (M1)

\n

t1-t2=2-32

\n

0.5 minutes (30 seconds)         A1

\n

 

\n

[2 marks]

\n
d.ii.
\n
\n

EITHER

\n

attempts to find rB-rA           (M1)

\n

rB-rA=-18111+t100-6

\n

attempts to find their D(t)           (M1)

\n

D(t)=10t-182+1+11-6t2         A1

\n


OR

\n

attempts to find rA-rB           (M1)

\n

rA-rB=18-1-11+t-1006

\n

attempts to find their D(t)           (M1)

\n

D(t)=18-10t2+-12+-11+6t2         A1

\n

 

\n

Note: Award M0M0A0 for expressions using two different time parameters.

\n


THEN

\n

either attempts to find the local minimum point of D(t) or attempts to find the value of t such that D'(t)=0  (or equivalent)           (M1)

\n

t=1.8088 =12368

\n

D(t)=1.01459

\n

minimum value of D(t) is 1.01 =119034 (km)         A1

\n


Note: Award M0 for attempts at the shortest distance between two lines.

\n

 

\n

[5 marks]

\n
e.
\n
", "Examiners report": "
\n

General comment about this question: many candidates were not exposed to this setting of vectors question and were rather lost.

\n

Part (a) Probably the least answered question on the whole paper. Many candidates left it blank, others tried using 3D vectors. Out of those who calculated the angle correctly, only a small percentage were able to provide the correct true bearing as a 3-digit figure.

\n

Part (b) Well done by many candidates who used the direction vectors to calculate and compare the speeds. A number of candidates tried to use the average rate of change but mostly unsuccessfully.

\n

Part (c) Most candidates used the correct vectors and the formula to obtain the obtuse angle. Then only some read the question properly to give the acute angle in degrees, as requested.

\n

Part (d) Well done by many candidates who used two different parameters. They were able to solve and obtain two values for time, the difference in minutes and the correct point of intersection. A number of candidates only had one parameter, thus scoring no marks in part (d) (i). The frequent error in part (d)(ii) was providing incorrect units.

\n

Part (e) Many correct answers were seen with an efficient way of setting the question and using their GDC to obtain the answer, graphically or numerically. Some gave time only instead of actually giving the minimal distance. A number of candidates tried to find the distance between two skew lines ignoring the fact that the lines intersect.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.i.
\n
\n[N/A]\n
d.ii.
\n
\n[N/A]\n
e.
\n
", "question_id": "22M.2.AHL.TZ2.11", "topics": [ "topic-3-geometry-and-trigonometry", "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-3-3-applications-angles-of-elevation-and-depression-bearings", "ahl-3-12-vector-definitions", "ahl-3-13-scalar-(dot)-product", "sl-2-10-solving-equations-graphically-and-analytically", "sl-5-8-testing-for-max-and-min-optimisation-points-of-inflexion" ] }, { "Question": "
\n

The population, P, of a particular species of marsupial on a small remote island can be modelled by the logistic differential equation

\n

dPdt=kP1-PN

\n

where t is the time measured in years and k, N are positive constants.

\n

The constant N represents the maximum population of this species of marsupial that the island can sustain indefinitely.

\n
\n

Let P0 be the initial population of marsupials.

\n
\n

In the context of the population model, interpret the meaning of dPdt.

\n
[1]
\n
a.
\n
\n

Show that d2Pdt2=k2P1-PN1-2PN.

\n
[4]
\n
b.
\n
\n

Hence show that the population of marsupials will increase at its maximum rate when P=N2. Justify your answer.

\n
[5]
\n
c.
\n
\n

Hence determine the maximum value of dPdt in terms of k and N.

\n
[2]
\n
d.
\n
\n

By solving the logistic differential equation, show that its solution can be expressed in the form

\n

kt=lnPP0N-P0N-P.

\n
[7]
\n
e.
\n
\n

After 10 years, the population of marsupials is 3P0. It is known that N=4P0.

\n

Find the value of k for this population model.

\n
[2]
\n
f.
\n
", "Markscheme": "
\n

rate of growth (change) of the (marsupial) population (with respect to time)       A1

\n

 

\n

[1 mark] 

\n


Note:
Do not accept growth (change) in the (marsupials) population per year.

\n
a.
\n
\n

METHOD 1

\n

attempts implicit differentiation on dPdt=kP-kP2N be expanding kP1-PN       (M1)

\n

d2Pdt2=kdPdt-2kPNdPdt       A1A1

\n

=kdPdt1-2PN       A1

\n

dPdt=kP1-PN and so d2Pdt2=k2P1-PN1-2PN       AG

\n

 

\n

METHOD 2

\n

attempts implicit differentiation (product rule) on dPdt=kP1-PN        M1

\n

d2Pdt2=kdPdt1-PN+kP-1NdPdt        A1

\n

substitutes dPdt=kP1-PN into their d2Pdt2        M1

\n

d2Pdt2=kkP1-PN1-PN+kP-1NkP1-PN

\n

=k2P1-PN2-k2P1-PNPN

\n

=k2P1-PN1-PN-PN        A1

\n

so d2Pdt2=k2P1-PN1-2PN        AG

\n

 

\n

[4 marks] 

\n
b.
\n
\n

d2Pdt2=0k2P1-PN1-2PN=0         (M1)

\n

P=0,N2,N          A2

\n

Note: Award A1 for P=N2 only.

\n

uses the second derivative to show that concavity changes at P=N2 or the first derivative to show a local maximum at P=N2          M1

EITHER

\n

a clearly labelled correct sketch of d2Pdt2 versus P showing P=N2 corresponding to a local maximum point for dPdt           R1

\n

\n


OR

\n

a correct and clearly labelled sign diagram (table) showing P=N2 corresponding to a local maximum point for dPdt            R1

\n


OR

\n

for example, d2Pdt2=3k2N32>0 with P=N4 and d2Pdt2=3k2N32<0 with P=3N4 showing P=N2 corresponds to a local maximum point for dPdt            R1

\n

so the population is increasing at its maximum rate when P=N2         AG

\n

 

\n

[5 marks] 

\n
c.
\n
\n

substitutes P=N2 into dPdt         (M1)

\n

dPdt=kN21-N2N

\n

the maximum value of dPdt is kN4          A1

\n

 

\n

[2 marks]

\n
d.
\n
\n

METHOD 1

\n

attempts to separate variables          M1

\n

NPN-PdP=kdt

\n

attempts to write NPN-P in partial fractions form         M1

\n

NPN-PAP+BN-PNAN-P+BP

\n

A=1, B=1         A1

\n

NPN-P1P+1N-P

\n

1P+1N-PdP=kdt

\n

lnP-lnN-P=kt+C         A1A1

\n


Note: Award A1 for -lnN-P and A1 for lnP and kt+C. Absolute value signs are not required.

\n

 

\n

attempts to find C in terms of N and P0         M1

\n

when t=0, P=P0 and so C=lnP0-lnN-P0

\n

kt=lnPN-P-lnP0N-Po =lnPN-PP0N-P0         A1

\n

so kt=lnPP0N-P0N-P         AG

\n

 

\n

METHOD 2

\n

attempts to separate variables          M1

\n

1P1-PNdP=kdt

\n

attempts to write 1P1-PN in partial fractions form         M1

\n

1P1-PNAP+B1-PN1A1-PN+BP 

\n

 A=1, B=1N         A1

\n

1P1-PN1P+1N1-PN

\n

1P+1N1-PNdP=kdt

\n

lnP-ln1-PN=kt+C         A1A1

\n


Note:
 Award A1 for -ln1-PN and A1 for lnP and kt+C. Absolute value signs are not required.

\n


lnP1-PN=kt+ClnNPN-P=kt+C

\n

attempts to find C in terms of N and P0         M1

\n

when t=0, P=P0 and so C=lnNP0N-P0

\n

kt=lnNPN-P-lnNP0N-P0 =lnPN-PP0N-P0         A1

\n

kt=lnPP0N-P0N-P         AG

\n

 

\n

METHOD 3

\n

lets u=1P and forms dudt=-1P2dPdt          M1

\n

multiplies both sides of the differential equation by -1P2 and makes the above substitutions          M1

\n

-1P2dPdt=k1N-1Pdudt=k1N-u

\n

dudt+ku=kN (linear first-order DE)         A1

\n

IF=ekdt=ektektdudt+kektu=kNekt         (M1)

\n

ddtuekt=kNekt

\n

uekt=1Nekt+C 1Pekt=1Nekt+C         A1

\n

attempts to find C in terms of N and P0         M1

\n

when t=0, P=P0, u=1P0 and so C=1P0-1N=N-P0NP0

\n

ektN-PNP=N-P0NP0

\n

ekt=PN-PN-P0P0         A1

\n

kt=lnPP0N-P0N-P         AG

\n

 

\n

[7 marks]

\n
e.
\n
\n

substitutes t=10, P=3P0 and N=4P0 into kt=lnPP0N-P0N-P          M1

\n

10k=ln34P0-P04P0-3P0  =ln9

\n

k=0.220  =110ln9,=15ln3         A1

\n

 

\n

[2 marks]

\n
f.
\n
", "Examiners report": "
\n

An extremely tricky question even for the strong candidates. Many struggled to understand what was expected in parts (b) and (c). As the question was set all with pronumerals instead of numbers many candidates found it challenging, thrown at deep water for parts (b), (c) and (e). It definitely was the question to show their skills for the Level 7 candidates provided that they did not run out of time.

\n

Part (a) Very well answered, mostly correctly referring to the rate of change. Some candidates did not gain this mark because their sentence did not include the reference to the rate of change. Worded explanations continue being problematic to many candidates.

\n

Part (b) Many candidates were confused how to approach this question and did not realise that they
needed to differentiate implicitly. Some tried but with errors, some did not fully show what was required.

\n

Part (c) Most candidates started with equating the second derivative to zero. Most gave the answer P=N2omitting the other two possibilities. Most stopped here. Only a small number of candidates provided the correct mathematical argument to show it is a local maximum.

\n

Part (d) Well done by those candidates who got that far. Most got the correct answer, sometimes not fully simplified.

\n

Part (e) Most candidates separated the variables, but some were not able to do much more. Some candidates knew to resolve into partial fractions and attempted to do so, mainly successfully. Then they integrated, again, mainly successfully and continued to substitute the initial condition and manipulate the equation accordingly.

\n

Part (f) Algebraic manipulation of the logarithmic expression was too much for some candidates with a common error of 0.33 given as the answer. The strong candidates provided the correct exact or rounded value.

\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
\n[N/A]\n
d.
\n
\n[N/A]\n
e.
\n
\n[N/A]\n
f.
\n
", "question_id": "22M.2.AHL.TZ2.12", "topics": [ "topic-5-calculus", "topic-1-number-and-algebra", "topic-2-functions" ], "subtopics": [ "sl-5-1-introduction-of-differential-calculus", "sl-5-6-differentiating-polynomials-n-e-q-chain-product-and-quotient-rules", "sl-5-7-the-second-derivative", "sl-1-7-laws-of-exponents-and-logs", "sl-2-10-solving-equations-graphically-and-analytically" ] }, { "Question": "
\n

A quadratic function \nf\n can be written in the form \nf\n(\nx\n)\n=\na\n(\nx\n\np\n)\n(\nx\n\n3\n)\n. The graph of \nf\n has axis of symmetry \nx\n=\n2.5\n and \ny\n-intercept at \n(\n0\n,\n\n \n\n\n6\n)\n

\n
\n

Find the value of  p .

\n
[3]
\n
a.
\n
\n

Find the value of  a .

\n
[3]
\n
b.
\n
\n

The line  y = k x 5  is a tangent to the curve of  f . Find the values of  k .

\n
[8]
\n
c.
\n
", "Markscheme": "
\n

METHOD 1 (using x-intercept)

\n

determining that 3 is an  x -intercept     (M1)

\n

eg x 3 = 0 \"M17/5/MATME/SP1/ENG/TZ1/09.a/M\"

\n

valid approach     (M1)

\n

eg 3 2.5 ,   p + 3 2 = 2.5

\n

p = 2      A1     N2

\n

METHOD 2 (expanding (x)) 

\n

correct expansion (accept absence of  a )     (A1)

\n

eg a x 2 a ( 3 + p ) x + 3 a p ,   x 2 ( 3 + p ) x + 3 p

\n

valid approach involving equation of axis of symmetry     (M1)

\n

eg b 2 a = 2.5 ,   a ( 3 + p ) 2 a = 5 2 ,   3 + p 2 = 5 2

\n

p = 2      A1     N2

\n

METHOD 3 (using derivative)

\n

correct derivative (accept absence of  a )     (A1)

\n

eg a ( 2 x 3 p ) ,   2 x 3 p

\n

valid approach     (M1)

\n

eg f ( 2.5 ) = 0

\n

p = 2      A1     N2

\n

[3 marks]

\n
a.
\n
\n

attempt to substitute  ( 0 ,   6 )      (M1)

\n

eg 6=a(02)(03), a(0)25a(0)+6a=6

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correct working     (A1)

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eg 6 = 6 a

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a = 1      A1     N2

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[3 marks]

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b.
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METHOD 1 (using discriminant)

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recognizing tangent intersects curve once     (M1)

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recognizing one solution when discriminant = 0     M1

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attempt to set up equation     (M1)

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eg g = f ,   k x 5 = x 2 + 5 x 6

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rearranging their equation to equal zero     (M1)

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eg x 2 5 x + k x + 1 = 0

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correct discriminant (if seen explicitly, not just in quadratic formula)     A1

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eg ( k 5 ) 2 4 ,   25 10 k + k 2 4

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correct working     (A1)

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eg k 5 = ± 2 ,   ( k 3 ) ( k 7 ) = 0 ,   10 ± 100 4 × 21 2

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k = 3 ,   7      A1A1     N0

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METHOD 2 (using derivatives)

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attempt to set up equation     (M1)

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eg g = f ,   k x 5 = x 2 + 5 x 6

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recognizing derivative/slope are equal     (M1)

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eg f = m T ,   f = k

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correct derivative of  f      (A1)

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eg 2 x + 5

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attempt to set up equation in terms of either  x  or  k      M1

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eg ( 2 x + 5 ) x 5 = x 2 + 5 x 6 ,   k ( 5 k 2 ) 5 = ( 5 k 2 ) 2 + 5 ( 5 k 2 ) 6

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rearranging their equation to equal zero     (M1)

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eg x 2 1 = 0 ,   k 2 10 k + 21 = 0

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correct working     (A1)

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eg x = ± 1 ,   ( k 3 ) ( k 7 ) = 0 ,   10 ± 100 4 × 21 2

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k = 3 ,   7      A1A1     N0

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[8 marks]

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c.
\n
", "Examiners report": "
\n[N/A]\n
a.
\n
\n[N/A]\n
b.
\n
\n[N/A]\n
c.
\n
", "question_id": "17M.1.SL.TZ1.S_9", "topics": [ "topic-2-functions", "topic-5-calculus" ], "subtopics": [ "sl-2-6-quadratic-function", "sl-5-3-differentiating-polynomials-n-e-z" ] } ]