section a question 1 caps 2018 prelim papers/st marys … · 1 section a question 1 in the diagram,...

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1 SECTION A QUESTION 1 In the diagram, P, Q(−7; −2), R and S(3; 6) are vertices of a quadrilateral. R is a point on the -axis. QR is produced to N. SN is drawn. PT O = 71,57° and SR N=. SR-axis. Determine: (a) The equation of SR. (1) _______________________________________________________________ (b) The gradient of QP correct to the nearest integer. (2) _______________________________________________________________ _______________________________________________________________ (c) The equation of QP in the form = + . (2) _______________________________________________________________ _______________________________________________________________ _______________________________________________________________ T 71,57° Q(−7; −2) N R P S (3; 6) T

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Page 1: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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SECTION A

QUESTION 1

In the diagram, P, Q(−7; −2), R and S(3; 6) are vertices of a quadrilateral. R is a point

on the 𝑥-axis. QR is produced to N. SN is drawn. PTO = 71,57° and SRN = 𝜃.

SRꞱ 𝑥-axis.

Determine:

(a) The equation of SR. (1)

_______________________________________________________________

(b) The gradient of QP correct to the nearest integer. (2)

_______________________________________________________________

_______________________________________________________________

(c) The equation of QP in the form 𝑦 = 𝑚𝑥 + 𝑐. (2)

_______________________________________________________________

_______________________________________________________________

_______________________________________________________________

𝜃 T 71,57°

Q(−7; −2)

N

R

P

𝑥

𝑦

S (3; 6)

T

Page 2: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(d) (1) The angle of inclination of QN, 𝛽, correct to one decimal place. (3)

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(2) Hence, determine 𝜃. (2)

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(e) The length of QR. Leave your answer in simplest surd form. (2)

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(f) If QR = 2RN determine the area of ∆RSN, correct to the nearest square unit. (4)

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Page 3: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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QUESTION 2

A local supermarket is running a campaign for shoppers to use fewer single use

plastic bags in their weekly shopping trips. The supermarket recorded the amount of

single use plastic bags requested by shoppers as the campaign continued. The

results are shown below:

Number of weeks in

campaign

1 2 3 4 5 7 8 10

Number of plastic bags

requested

12 10 7 7 6 2 3 2

(a) Use the scatter plot to comment on the relationship between the number of

plastic bags shoppers requested and the weeks the campaign was running. (2)

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0

2

4

6

8

10

12

14

0 2 4 6 8 10 12

Nu

mb

er o

f p

last

ic b

ags

use

d p

er w

eek

Number of Shopping Trips per week

Scatter plot

Page 4: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(b) Use your calculator to determine the correlation coefficient of the data, correct

to two decimal places. (1)

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(c) Use your calculator to assist you in determining the equation of the least

squares regression line of the data. Round 𝑎 and 𝑏 values to two decimal

places. (3)

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(d) Use your model from question 2(c) to estimate the average number of plastic

bags a person who goes shopping in the 6th week of the campaign will request,

correct to the nearest whole number. (2)

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[8]

QUESTION 3

(a) Simplify sin(180° − 𝑥) . cos(−𝑥) + cos(90° + 𝑥) . cos (𝑥 − 180°) to a single

trigonometric ratio. (6)

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Page 5: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(b) Determine the value of sin3𝑥. cos𝑦 + cos3𝑥. sin𝑦 if 3𝑥 + 𝑦 = 270° (3)

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(c) If cos𝜃 = −5

6, where 𝜃 ∈ [180°; 270°], calculate, without using a calculator and

with the aid of a sketch, the values in simplest form of:

(1) sin𝜃 (3)

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(2) sin2 𝜃 (3)

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Page 6: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(d) (1) Show that: 2sin𝑥

2(1−cos2𝑥)=

1

2𝑠𝑖𝑛𝑥 (4)

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(2) For which values of 𝑥 is the identity undefined. (3)

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(e) Consider: 𝑔(𝑥) = −4 cos(𝑥 + 30°)

(1) Draw a sketch of 𝑔 on the system of axes below for 𝑥 ∈ [−180°; 360°] (6)

Page 7: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(2) Determine the period of 𝑔(3𝑥). (2)

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(3) Determine the range of 𝑔(𝑥) + 1 (1)

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(4) The graph of 𝑔 is shifted 60° to the right and then reflected about the 𝑥-

axis to form a new graph ℎ. Determine the equation of ℎ in its simplest

form. (2)

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[33]

Page 8: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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QUESTION 4

(a) ABC is a tangent to the circle BFE at B. From C a straight line is drawn parallel

to BF to meet FE produced at D. EC and BD are drawn. E1 = E2 = 𝑥 and C2 = 𝑦.

(1) Give a reason why each of the following is true:

(i) B1 = 𝑥 (1)

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(ii) BCD = B1 (1)

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(iii) Hence, show that BCDE is a cyclic quadrilateral. (2)

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A

B

C

D

E

F

1 2 3

4

1

2 3

1

2

2 1

𝑥

𝑥

𝑦

Page 9: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(2) Which two angles are each equal to 𝑥? Give reasons for your answer. (2)

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(3) Prove that B2 = C1, giving reasons for your answer. (3)

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(b) PR is a diameter of the circle PRSU. QU is drawn parallel to RS and meets SP in

T.

(1) Determine the size of S giving a reason for your answer. (2)

_______________________________________________________________

_______________________________________________________________

R S

Q

P

U T

1

2

Page 10: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(2) If the diameter is 20 cm and SP = 16 cm:

(i) Calculate the length of QT. Giving reasons for your answer. (5)

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(ii) Hence determine the length of TU. (1)

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[17]

74 MARKS

Page 11: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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SECTION B

QUESTION 5

(a) 𝑥2 + 𝑦2 + 8𝑥 − 6𝑦 = −5, is the equation of the circle with centre M. UE is a

tangent to the circle at Q. QMD, DA, AU and UQE are straight lines. DU is parallel

to the 𝑥-axis.

(1) Determine the coordinates of M, the centre of the circle. (4)

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A(0; 11)

𝑦

𝑥

M

D(−10; 6) U

Q

E

Page 12: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(2) Calculate the coordinates of Q, if 𝑦 < 2. (3)

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(3) Determine the equation of the tangent UE. (4)

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Page 13: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(b) The diagram represents a model of a steel arch which is an arc of a circle

centre C. The width, AB, of the arch is 16 metres and its maximum height, EO,

is 2 metres.

One of the vertical pillars that supports the arch is at point P the midpoint of

AO, where O is the point (0; 0).

(1) Determine the equation of the circle with centre C in the form:

𝑥2 + 𝑦2 + 𝑐𝑥 + 𝑑𝑦 + 𝑒 = 0. (5)

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Q

E

𝑥

A

C

B

𝑦

P O

C

Page 14: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(2) Determine the height of the pillar PQ correct to one decimal digit given that

Q is a point on the arc. (3)

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[19]

QUESTION 6

(a) Given: 2cos𝑥 = 3tan𝑥

(1) Show that the equation can be rewritten as 2 sin2 𝑥 + 3sin𝑥 − 2 = 0 (4)

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Page 15: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(2) Hence, determine the general solution of 𝑥 if 2cos𝑥 = 3tan𝑥 (4)

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(3) Hence, determine two values of 𝑦, 𝑦 ∈ [150°; 180°], that are solutions of

2cos5𝑦 = 3tan5𝑦. (4)

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[12]

Page 16: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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QUESTION 7

Study the three histograms given below and answer the questions that follow.

(a) Which set of data (A, B, or C) has the smallest standard deviation? Explain

your answer. (2)

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(b) For data set A the mean is 3,5 and the standard deviation is 1,2. (2)

The values of the data set are doubled.

Determine the mean and standard deviation of the new data set.

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Page 17: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(c) The table below represents data set C. (2)

CLASS INTERVAL FREQUENCY

0 ≤ 𝑥 < 2 𝑎

2 ≤ 𝑥 < 4 𝑏

4 ≤ 𝑥 < 6 𝑐

6 ≤ 𝑥 < 8 𝑑

8 ≤ 𝑥 < 10 𝑒

It is given that the mean is 𝑝 and the standard deviation is 𝑞.

If it is given that the frequency of each class interval is doubled , write down the

mean and standard deviation of the new data set in terms of 𝑝 and 𝑞.

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[6]

Page 18: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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QUESTION 8

The diagram, represents one of the right cylindrical silos above. M is the centre of

the circular base with BA and BC tangents to the base at A and C. MA, the radius of

the circular base is r. A, B and C lie on the same horizontal plane. DC represents the

vertical height of the cylindrical part of the silo.

BAC = 𝛼 and DBC = 𝜃. DC = h and AB = BC = d.

D

h

C

d

B

A

M r

𝛼

𝜃 d

Page 19: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(a) Prove that AC = d√2 + 2cos2𝛼 (5)

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(b) Hence, prove that ACtan𝜃

√2+2cos2𝛼= h (4)

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Page 20: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(c) If h = 36 metres, d = 10,3 metres and 𝛼 = 54°:

(1) Prove that AC = 12,22 metres. (2)

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(2) Find ABC correct to two decimal places. (2)

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(3) If AMCB is a cyclic quadrilateral determine the size of M. (1)

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(4) Show that r = 7,59 metres. (4)

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(5) Find the volume of the silo, correct to the nearest cubic metre. (2)

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[20]

Page 21: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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QUESTION 9

(a) Complete the theorem statement: (2)

A line drawn parallel to one side of a triangle divides

____________________________________________________________.

(b) In the accompanying diagram DE is a tangent to the circle at E. DFG is a secant.

DE = EF = FG; FH || DE and E1 = 𝜃

(1) State, with reasons, three angles each equal to 𝜃. (3)

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D E

H

G

F

3 2

1 1

2

2 1

Page 22: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(2) Prove that:

(i) FE =GH.DF

HE (4)

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(ii) DE2 = DF. DG (5)

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Page 23: SECTION A QUESTION 1 CAPS 2018 Prelim Papers/St Marys … · 1 SECTION A QUESTION 1 In the diagram, P,Q(−7;−2),Rand S(3;6) are vertices of a quadrilateral. R is a point on the

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(3) If DF

DE= 𝑦, show that 𝑦2 + 𝑦 = 1 (5)

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76 MARKS

TOTAL: 150 MARKS