Mathematics 7356: Trigonometry Topical Past Paper Questions

One of the equations below is true for all values of x Identify the correct equation. Tick (✓) one box. [1 mark] \[\begin{aligned}&\cos^{2}x=-1-\sin^{2}x\\ &\quad\quad\

It is given that $ \sin 15^{\circ} = \frac{\sqrt{6} - \sqrt{2}}{4} $ and $ \cos 15^{\circ} = \frac{\sqrt{6} + \sqrt{2}}{4} $. Use these two expressions to show that $ \tan 15^{\circ} = 2 - \sqrt{3} $ Fully justify your answer. [4 marks]

Triangle ABC has sides of length $ (m-n) $, m and $ (m+n) $ where $ 0 < 2n < m $ Angle A is the largest angle in the triangle. (a) (i) Explain why angle A must be opposite the side of length $ (m + n) $. [1 mark] (a) (ii) Using the cosine rule, show that $ \cos A = \frac{m - 4n}{…