9709 P13 - Nov 2014 - Q5 - 7 marks
405
(i) Show that \(\sin^4 \theta - \cos^4 \theta \equiv 2 \sin^2 \theta - 1\).
(ii) Hence solve the equation \(\sin^4 \theta - \cos^4 \theta = \frac{1}{2}\) for \(0^\circ \leq \theta \leq 360^\circ\).
Solutions locked. Please sign in with access to view them.