Here's another example to work through. This time you need to draw two right-angled triangles to help you with your working. If \(\sin p = \frac{3}{5}\) and \(\tan q ...

The double angle formulae are: \(\sin 2A = 2\sin A\cos A\) \(\cos 2A = {\cos ^2}A - {\sin ^2}A\) \(= 2{\cos ^2}A - 1\) \(= 1 - 2{\sin ^2}A\) Solve the equation \(5 ...