Trigonometrymedium · Past Paper
Simplify: 4 sin³ 10° - 3 sin 10°.
Asin 30°
B-sin 30°
Ccos 30°
D1/2
✓ Correct Answer: B — -sin 30°
Since sin 3θ = 3 sin θ - 4 sin³ θ, the given expression is -(3 sin 10 - 4 sin³ 10) = -sin 30°.
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