Question

Write as a single trigonometric function:

(a) \(2 \sin x \cdot \cos x\)
(b) \(2 \sin 3 \mathrm{~A} \cdot \cos 3 \mathrm{~A}\)
(c) \(2 \sin 20^{\circ} \cdot \cos 20^{\circ}\)
(d) \(2 \sin 35^{\circ} \cdot \cos 35^{\circ}\)
(e) \(4 \sin \theta \cdot \cos \theta\)
(f) \(\cos ^2 3 \theta-\sin ^2 3 \theta\)
(g) \(2 \cos ^2 2 \theta-1\)
(h) \(1-2 \sin ^2 \frac{\alpha}{2}\)
(i) \(\sin ^2 42^{\circ}-\cos ^2 42^{\circ}\)
(j) \(1-2 \cos ^2 22^{\circ}\)
(k) \((\cos 2 \theta+\sin 2 \theta)(\cos 2 \theta-\sin 2 \theta)\)
(1) \(\sin \theta \cos \theta\)