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Edexcel GCSE Maths (Non-calculator) Smart practice A mixed round aimed at your weak spots
Unit 1
Number
Unit 2
Algebra
Unit 3
Ratio, proportion and rates of change
Unit 4
Geometry and measures
Unit 5
Probability
Unit 6
Statistics
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Exact trigonometric values

Practise 29 exam-style questions on Exact trigonometric values for Edexcel GCSE Maths (Non-calculator). Write your answer as you would in the exam and get it marked in seconds against the mark scheme, point by point, with an AI tutor on hand if you get stuck.

  • 29 questions
  • 1–5 marks each
  • Instant marking
  • No sign-up needed
20 questions, marked as you go

Sample questions with model answers

Here are 4 of the questions in this topic, each with a model answer, an explanation of why it earns the marks and the mark scheme an examiner would use.

Question 1

2 marks

Work out the exact value of \(\sin 60° \times \cos 30°\).

Model answer

\(\sin 60° \times \cos 30° = \dfrac{\sqrt{3}}{2} \times \dfrac{\sqrt{3}}{2} = \dfrac{3}{4}\)

Explanation

Both values are \(\dfrac{\sqrt{3}}{2}\). Multiplying, \(\sqrt{3} \times \sqrt{3} = 3\) and \(2 \times 2 = 4\).

Mark scheme
  1. 1 mark

    M1 for \(\dfrac{\sqrt{3}}{2} \times \dfrac{\sqrt{3}}{2}\)

    both values correct; correct answer with no working scores full marks

  2. 1 mark

    A1 for \(\dfrac{3}{4}\)

    oe, e.g. 0.75

Question 2

2 marks

Show that \(\cos 30° \times \tan 30° = \sin 30°\)

Model answer

\(\cos 30° \times \tan 30° = \dfrac{\sqrt{3}}{2} \times \dfrac{1}{\sqrt{3}} = \dfrac{1}{2}\)
\(\sin 30° = \dfrac{1}{2}\)
So \(\cos 30° \times \tan 30° = \sin 30°\)

Explanation

Substitute the exact values and cancel the \(\sqrt{3}\). This works for any acute angle, because \(\tan x = \dfrac{\sin x}{\cos x}\), so \(\cos x \times \tan x = \sin x\).

Mark scheme
  1. 1 mark

    M1 for \(\dfrac{\sqrt{3}}{2} \times \dfrac{1}{\sqrt{3}}\)

    oe, e.g. \(\dfrac{\sqrt{3}}{2} \times \dfrac{\sqrt{3}}{3}\)

  2. 1 mark

    C1 for simplifying to \(\dfrac{1}{2}\) and stating \(\sin 30° = \dfrac{1}{2}\)

    answer only scores 0 (show that)

Question 3

3 marks

The diagram shows an equilateral triangle ABC with sides of length 2 cm.
M is the midpoint of BC and AM is perpendicular to BC.

Use the triangle to show that \(\sin 60° = \dfrac{\sqrt{3}}{2}\)

Geometry diagram, marked "Diagram NOT accurately drawn". Triangle ABC. Line segment AM is drawn. M lies on side BC. Angle AMC is marked as a right angle (90°). Angle ABM is marked 60°. Side AB is labelled 2 cm. AB, BC and CA are each marked with one short dash (equal lengths).

Model answer

Each angle of an equilateral triangle is 60°, so angle ABM = 60°.
BM = 2 ÷ 2 = 1 cm
In the right-angled triangle ABM: \(AM^2 = 2^2 - 1^2 = 3\), so \(AM = \sqrt{3}\) cm
\(\sin 60° = \dfrac{\text{opposite}}{\text{hypotenuse}} = \dfrac{AM}{AB} = \dfrac{\sqrt{3}}{2}\)

Explanation

Cutting an equilateral triangle of side 2 in half gives a right-angled triangle with angles 30°, 60°, 90° and sides 1, \(\sqrt{3}\), 2. All the exact values for 30° and 60° can be read from this triangle, so you can rebuild them if you forget.

Mark scheme
  1. 1 mark

    M1 for BM = 1

  2. 1 mark

    M1 for \(AM^2 = 2^2 - 1^2\), so \(AM = \sqrt{3}\)

  3. 1 mark

    C1 for \(\sin 60° = \dfrac{AM}{AB} = \dfrac{\sqrt{3}}{2}\), with angle ABM = 60° stated or used

    complete argument required

Question 4

4 marks

The diagram shows a regular hexagon with sides of length 4 cm.

Work out the exact area of the hexagon.
Give your answer in the form \(a\sqrt{3}\), where \(a\) is an integer.

Geometry diagram, marked "Diagram NOT accurately drawn". Regular hexagon ABCDEF. Side AB is labelled 4 cm.

Model answer

Joining the centre to each vertex makes 6 equilateral triangles with sides 4 cm.
Height of one triangle \(= 4 \sin 60° = 4 \times \dfrac{\sqrt{3}}{2} = 2\sqrt{3}\) cm
Area of one triangle \(= \dfrac{1}{2} \times 4 \times 2\sqrt{3} = 4\sqrt{3}\) cm²
Area of hexagon \(= 6 \times 4\sqrt{3} = 24\sqrt{3}\) cm²

Explanation

The angles at the centre of a regular hexagon are \(360° \div 6 = 60°\), so the six triangles are equilateral. The exact value \(\sin 60° = \dfrac{\sqrt{3}}{2}\) gives the height of each triangle.

Mark scheme
  1. 1 mark

    P1 for splitting the hexagon into 6 equilateral triangles of side 4 cm

    or other complete dissection; correct answer with no working scores full marks

  2. 1 mark

    P1 for the height of one triangle \(4 \sin 60°\) \((= 2\sqrt{3})\), or \(\dfrac{1}{2} \times 4 \times 4 \times \sin 60°\)

    oe, e.g. \(\sqrt{4^2 - 2^2} = \sqrt{12}\)

  3. 1 mark

    P1 for the area of one triangle \(4\sqrt{3}\)

    ft their height

  4. 1 mark

    A1 for \(24\sqrt{3}\)

    cao

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