Trigonometryhard · Past Paper
If A + B + C = π, then sin 2A + sin 2B + sin 2C is:
A4 sin A sin B sin C
B4 cos A cos B cos C
C2 sin A sin B sin C
D1 + 4 sin A sin B sin C
✓ Correct Answer: A — 4 sin A sin B sin C
This is a standard conditional identity for angles of a triangle.
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