KCSE PAST PAPERS

x. 3. tan 2 x sec 2 x − 1. 4.cot2 x = cosec2 x - 1. 5.2 sin A cos B = sin (A + B) + sin (A – B) 6.2 cos A cos B = cos (A + B) + cos (A – B) 7.-2 sin A sin B = cos (A+B) – cos (A – B) 8.sin 3x = 3 sin x – 4 sin3 x. 9.cos 3x = -3 cos x + 4 cos3 x ................
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