Trigonometrymedium · Past Paper
What is sin(A - B) cos B + cos(A - B) sin B?
Asin A
Bcos A
Csin(A - 2B)
D0
✓ Correct Answer: A — sin A
Let X = A-B. The expression is sin X cos B + cos X sin B = sin(X + B) = sin(A - B + B) = sin A.
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