Trigonometrymedium · Past Paper
If sin A = 4/5, find sin(2A).
A8/5
B24/25
C12/25
D6/5
✓ Correct Answer: B — 24/25
cos A = 3/5. sin(2A) = 2 sin A cos A = 2 * (4/5) * (3/5) = 24/25.
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