Trigonometryhard · Past Paper
In triangle ABC, right angled at C, if tan A = 1/sqrt(3), find sin A cos B + cos A sin B.
A0
B1/2
C1
Dsqrt(3)/2
✓ Correct Answer: C — 1
tan A = 1/sqrt(3) means A = 30. Since C = 90, B = 60. sin 30 cos 60 + cos 30 sin 60 = 1/2*1/2 + sqrt(3)/2*sqrt(3)/2 = 1/4 + 3/4 = 1.
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