(a) Using a scale of 2 cm to 30° on the x- axis, 2 cm to 0.2 units on the y- axis, on the same graph sheet, draw the graphs of \(y = \sin 2x\) and \(y = \cos x\) for \(0° \leq x \leq 210°\) at intervals of 30°.

(b) Using the graphs in (a), find the truth set of :

(i) \(\sin 2x = 0\) ; (ii) \(\sin 2x - \cos x = 0\).