National 5 Maths · SQA past paper

2018 Paper 1

Non-Calculator · 19 questions
1

Question 1

Fractions and mixed numbers
2 Marks
2018 P1 Q1
Evaluate 213+45.\displaystyle 2 \frac{1}{3}+\frac{4}{5}.
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3215\displaystyle 3\frac{2}{15}
2

Question 2

Expanding brackets
3 Marks
2018 P1 Q2

Expand and simplify (3x+1)(x1)+2(x25)\displaystyle (3x+1)(x-1)+2(x^2-5).

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5x22x11\displaystyle 5x^2-2x-11
3

Question 3

Simultaneous equations
3 Marks
2018 P1 Q3

Solve, algebraically, the system of equations

4x+5y=36x2y=5\begin{aligned} 4x + 5y &= -3 \\ 6x - 2y &= 5 \end{aligned}

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x=12,y=1\displaystyle x=\frac{1}{2}, y=-1
4

Question 4

Adding and Subtracting vector components
2 Marks
2018 P1 Q4

Two vectors are given by u=(151)\displaystyle \mathbf{u}=\begin{pmatrix}1\\ 5\\ 1\end{pmatrix} and u+v=(643)\displaystyle \mathbf{u}+\mathbf{v}=\begin{pmatrix}6\\ -4\\ 3\end{pmatrix}.
Find vector v\displaystyle \mathbf{v}.
Express your answer in component form.

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(592)\displaystyle \begin{pmatrix}5\\ -9\\ 2\end{pmatrix}
5

Question 5

Quadratic equation by factorising
2 Marks
2018 P1 Q5

Solve x211x+24=0.\displaystyle x^{2}-11x+24=0.

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x=3,x=8\displaystyle x=3, x=8
6

Question 6

Identify equation of trigonometric graph
2 Marks
2018 P1 Q6

Part of the graph of y=acosbx\displaystyle y=a\cos bx^{\circ} is shown in the diagram.

Graph of y=a cos bx

State the values of a\displaystyle a and b.\displaystyle b.

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a=5,b=4\displaystyle a=5, b=4
7

Question 7

Straight Line Equation
(3, 1)4 Marks
2018 P1 Q7

The cost of a journey with Tom's Taxis depends on the distance travelled. The graph below shows the cost, P\displaystyle P pounds, of a journey with Tom's Taxis against the distance travelled, d\displaystyle d miles.

Line graph showing cost vs distance

Point A represents a journey of 8 miles which costs £14.
Point B represents a journey of 12 miles which costs £20.

(a)  Find the equation of the line in terms of P\displaystyle P and d\displaystyle d. Give the equation in its simplest form.
(b)  Calculate the cost of a journey of 5 miles.

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(a) P=32d+2\displaystyle P=\frac{3}{2}d+2 or 2P=3d+4\displaystyle 2P=3d+4, (b) £9.50
8

Question 8

Discriminant
2 Marks
2018 P1 Q8

Determine the nature of the roots of the function f(x)=2x2+4x+5\displaystyle f(x)=2x^{2}+4x+5.

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No real roots
9

Question 9

Angles in regular polygons
2 Marks
2018 P1 Q9

In the diagram shown below, ABCDEFGHJK is a regular decagon.
•  Angle KLJ is 17°.
•  AKL is a straight line.

Regular decagon diagram

Calculate the size of shaded angle KJL.

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127\displaystyle 127^{\circ}
10

Question 10

Cosine rule: calculate length
3 Marks
2018 P1 Q10

In triangle XYZ:
XZ=10\displaystyle XZ=10 centimetres
YZ=8\displaystyle YZ=8 centimetres
cosZ=18\displaystyle \cos Z = \frac{1}{8}

Triangle XYZ

Calculate the length of XY.

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12 cm
11

Question 11

Rationalising the denominatorSimplifying surds
2 Marks
2018 P1 Q11

Express 96\displaystyle \frac{9}{\sqrt{6}} with a rational denominator.
Give your answer in its simplest form.

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362\displaystyle \frac{3\sqrt{6}}{2}
12

Question 12

sin/cos/tan of related angles
1 Mark
2018 P1 Q12

Given that cos60=0.5\displaystyle \cos 60^{\circ}=0.5, state the value of cos240.\displaystyle \cos 240^{\circ}.

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-0.5
13

Question 13

3d Coordinates
2 Marks
2018 P1 Q13

The diagram shows a triangular prism, ABCDEF, relative to the coordinate axes.

Triangular prism in 3D space

A(4,0,5)\displaystyle A(4,0,5), E(2,0,0)\displaystyle E(2,0,0).
AD=AE\displaystyle AD=AE, DC=8\displaystyle DC=8 units.
Edges EF, DC and AB are parallel to the y-axis.
Write down the coordinates of B and C.

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B(4,8,5), C(6,8,0)
14

Question 14

Changing the subject of a formula
3 Marks
2018 P1 Q14

Change the subject of the formula y=gx+h\displaystyle y=g\sqrt{x}+h to x\displaystyle x.

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x=(yhg)2\displaystyle x=\left(\frac{y-h}{g}\right)^{2}
15

Question 15

Laws of indices
2 Marks
2018 P1 Q15

Remove the brackets and simplify (23p4)2\displaystyle (\frac{2}{3}p^{4})^{2}.

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49p8\displaystyle \frac{4}{9}p^{8}
16

Question 16

Sketch a parabola from equation
3 Marks
2018 P1 Q16

Sketch the graph of y=(x6)(x+4)\displaystyle y=(x-6)(x+4).
On your sketch, show clearly the points of intersection with the x-axis and the y-axis, and the coordinates of the turning point.

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Roots: -4, 6; y-intercept: -24; turning point: (1, -25)
17

Question 17

Volume - simple shape
3 Marks
2018 P1 Q17

A square based pyramid is shown in the diagram below.

Square based pyramid

The square base has length 6 centimetres.
The volume is 138 cubic centimetres.
Calculate the height of the pyramid.

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11.5 cm
18

Question 18

Trigonometric identities
2 Marks
2018 P1 Q18

Express sinxcosxtanx\displaystyle \sin x^{\circ}\cos x^{\circ}\tan x^{\circ} in its simplest form.
Show your working.

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sin2x\displaystyle \sin^{2}x^{\circ}
19

Question 19

Completing the squareTurning Points and Axis of Symmetry
(2, 1, 4)7 Marks
2018 P1 Q19

(a)  (i) Express x26x81\displaystyle x^{2}-6x-81 in the form (xp)2+q\displaystyle (x-p)^{2}+q.
      (ii) Hence state the equation of the axis of symmetry of the graph of y=x26x81\displaystyle y=x^{2}-6x-81.
(b)  The roots of the equation x26x81=0\displaystyle x^{2}-6x-81=0 can be expressed in the form x=d±de\displaystyle x=d \pm d\sqrt{e}. Find, algebraically, the values of d\displaystyle d and e\displaystyle e.

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(a) (i) (x3)290\displaystyle (x-3)^{2}-90, (ii) x=3\displaystyle x=3
(b) d=3,e=10\displaystyle d=3, e=10