Higher Maths · SQA past paper

2018 Paper 1

Non-Calculator · 15 questions
1

Question 1

Altitudes, medians, perpendicular bisectors
3 Marks
2018 P1 Q1

PQR is a triangle with vertices P(2,4)\displaystyle P(-2,4), Q(4,0)\displaystyle Q(4,0) and R(3,6)\displaystyle R(3,6).

Triangle PQR with vertices P(-2,4), Q(4,0) and R(3,6)

Find the equation of the median through R.

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y=2x\displaystyle y=2x
2

Question 2

Inverse functions
3 Marks
2018 P1 Q2

A function g(x)\displaystyle g(x) is defined on R\displaystyle \mathbb{R}, the set of real numbers, by
g(x)=15x4\displaystyle g(x)=\frac{1}{5}x-4
Find the inverse function, g1(x)\displaystyle g^{-1}(x).

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g1(x)=5(x+4)\displaystyle g^{-1}(x)=5(x+4)
3

Question 3

Differentiate or evaluate derivative: trigonometric expression
3 Marks
2018 P1 Q3

Given h(x)=3cos2x\displaystyle h(x)=3\cos 2x find the value of h(π6)\displaystyle h^{\prime}\left(\frac{\pi}{6}\right).

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33\displaystyle -3\sqrt{3}
4

Question 4

Equation of a tangent to a circle at a point
4 Marks
2018 P1 Q4

The point K(8,5)\displaystyle K(8,-5) lies on the circle with equation
x2+y212x6y23=0\displaystyle x^{2}+y^{2}-12x-6y-23=0

Circle with tangent at point K(8, -5)

Find the equation of the tangent to the circle at K.

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x4y28=0\displaystyle x-4y-28=0 or equivalent
5

Question 5

Ratio in which one point divides two others
(1, 1)2 Marks
2018 P1 Q5

A(3,4,7)\displaystyle A(-3,4,-7), B(5,t,5)\displaystyle B(5,t,5) and C(7,9,8)\displaystyle C(7,9,8) are collinear.
(a)  State the ratio in which B divides AC.
(b)  State the value of t\displaystyle t.

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(a) 4:1
(b) t=8\displaystyle t=8
6

Question 6

Simplify numerical expression involving logs/exponentials
3 Marks
2018 P1 Q6

Find the value of
log525013log58\displaystyle \log_{5}250-\frac{1}{3}\log_{5}8

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3
7

Question 7

Points of intersection of polynomial(s) and/or straight lineEquation of a tangent to a curve
(1, 3, 4)8 Marks
2018 P1 Q7

The curve with equation
y=x33x2+2x+5\displaystyle y=x^{3}-3x^{2}+2x+5
is shown on the diagram.

Curve y=x^3-3x^2+2x+5 intersecting tangent at P

(a)  Write down the coordinates of P, the point where the curve crosses the y-axis.
(b)  Determine the equation of the tangent to the curve at P.
(c)  Find the coordinates of Q, the point where this tangent meets the curve again.

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(a) (0,5)\displaystyle (0,5)
(b) y=2x+5\displaystyle y=2x+5
(c) Q(3,11)\displaystyle Q(3,11)
8

Question 8

Angles and straight lines: m = tanθ
2 Marks
2018 P1 Q8

A line has equation
y3x+5=0\displaystyle y-\sqrt{3}x+5=0
Determine the angle this line makes with the positive direction of the x-axis.

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60\displaystyle 60^{\circ} or π3\displaystyle \frac{\pi}{3} radians
9

Question 9

Vector pathways in geometric diagrams
(1, 2)3 Marks
2018 P1 Q9

The diagram shows a triangular prism ABC, DEF.
AB=t\displaystyle \vec{AB}=\mathbf{t}, AC=u\displaystyle \vec{AC}=\mathbf{u} and AD=v\displaystyle \vec{AD}=\mathbf{v}

Triangular prism ABC, DEF with vectors t, u, v

(a)  Express BC\displaystyle \vec{BC} in terms of u\displaystyle \mathbf{u} and t\displaystyle \mathbf{t}.
M is the midpoint of BC.
(b)  Express MD\displaystyle \vec{MD} in terms of t\displaystyle \mathbf{t}, u\displaystyle \mathbf{u} and v\displaystyle \mathbf{v}.

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(a) ut\displaystyle \mathbf{u}-\mathbf{t}
(b) v12t12u\displaystyle \mathbf{v}-\frac{1}{2}\mathbf{t}-\frac{1}{2}\mathbf{u}
10

Question 10

Differential equation
4 Marks
2018 P1 Q10

Given that
dydx=6x23x+4\displaystyle \frac{dy}{dx}=6x^{2}-3x+4
and y=14\displaystyle y=14 when x=2\displaystyle x=2, express y\displaystyle y in terms of x\displaystyle x.

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y=2x332x2+4x4\displaystyle y=2x^{3}-\frac{3}{2}x^{2}+4x-4
11

Question 11

Graphs of logarithmic or exponential functionsIdentifying/sketching graphs of related functions (non-trigonometric)
(2, 3)5 Marks
2018 P1 Q11

The diagram shows the curve with equation y=log3x\displaystyle y=\log_{3}x.

Graph of y=log3(x) passing through (1,0) and (3,1)

(a)  On the diagram in your answer booklet, sketch the curve with equation y=1log3x\displaystyle y=1-\log_{3}x.
(b)  Determine the exact value of the x-coordinate of the point of intersection of the two curves.

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(a) Sketch showing reflection in x-axis and translation 1 unit up.
(b) x=3\displaystyle x=\sqrt{3}
12

Question 12

Vector pathways in geometric diagrams
(1, 3)4 Marks
2018 P1 Q12

Vectors a\displaystyle \mathbf{a} and b\displaystyle \mathbf{b} are such that
a=4i2j+2k\displaystyle \mathbf{a}=4\mathbf{i}-2\mathbf{j}+2\mathbf{k} and b=2i+j+pk\displaystyle \mathbf{b}=-2\mathbf{i}+\mathbf{j}+p\mathbf{k}
(a)  Express 2a+b\displaystyle 2\mathbf{a}+\mathbf{b} in component form.
(b)  Hence find the values of p\displaystyle p for which 2a+b=7\displaystyle |2\mathbf{a}+\mathbf{b}|=7.

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(a) 6i3j+(4+p)k\displaystyle 6\mathbf{i}-3\mathbf{j}+(4+p)\mathbf{k}
(b) p=6,p=2\displaystyle p=-6, p=-2
13

Question 13

Apply double angle formula to simplify or evaluateApply compound angle formula to simplify or evaluate
(3, 1, 3)7 Marks
2018 P1 Q13

The right-angled triangle in the diagram is such that sinx=211\displaystyle \sin x=\frac{2}{\sqrt{11}} and 0<x<π4.\displaystyle 0 \lt x \lt \frac{\pi}{4}.

Right-angled triangle with hypotenuse sqrt(11) and opposite side 2

(a)  Find the exact value of:
      (i) sin2x\displaystyle \sin 2x
      (ii) cos2x\displaystyle \cos 2x
(b)  By expressing sin3x\displaystyle \sin 3x as sin(2x+x)\displaystyle \sin(2x+x), find the exact value of sin3x\displaystyle \sin 3x.

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(a)(i) 4711\displaystyle \frac{4\sqrt{7}}{11}, (ii) 311\displaystyle \frac{3}{11}
(b) 341111\displaystyle \frac{34}{11\sqrt{11}} or 3411121\displaystyle \frac{34\sqrt{11}}{121}
14

Question 14

Integrate (definite or indefinite): (px + q)^n
5 Marks
2018 P1 Q14

Evaluate
491(2x+9)23dx\displaystyle \int_{-4}^{9}\frac{1}{\sqrt[3]{(2x+9)^{2}}}dx

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3
15

Question 15

Identify polynomial equation when shown graph/rootsIncreasing/decreasing: show that, or find values for which
4 Marks
2018 P1 Q15

A cubic function, f\displaystyle f, is defined on the set of real numbers.
•  (x+4)\displaystyle (x+4) is a factor of f(x)\displaystyle f(x)
•  x=2\displaystyle x=2 is a repeated root of f(x)\displaystyle f(x)
•  f(2)=0\displaystyle f^{\prime}(-2)=0
•  f(x)>0\displaystyle f^{\prime}(x)>0 where the graph with equation y=f(x)\displaystyle y=f(x) crosses the y-axis

Sketch a possible graph of y=f(x)\displaystyle y=f(x) on the diagram in your answer booklet.

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Sketch of a cubic curve crossing the x-axis at -4, having a turning point at 2 (on the x-axis) and another turning point at -2. The graph should start from the top left (negative cubic).