Trigonometrymedium · Past Paper
Simplify: sin A cos A cos 2A.
A1/2 sin 4A
B1/4 sin 4A
Csin 4A
D1/4 cos 4A
✓ Correct Answer: B — 1/4 sin 4A
sin A cos A = 1/2 sin 2A. Thus, 1/2 sin 2A cos 2A = 1/4 sin 4A.
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