Given that theta is acute and sin(theta) = 3/5, find sin(2 theta).
Answer and explanation
Correct answer: C. 24/25
- Step 1: Since theta is acute, cos(theta) = sqrt(1 - sin^2(theta)) = 4/5.
- Step 2: sin(2 theta) = 2 sin(theta) cos(theta) = 2 x 3/5 x 4/5 = 24/25.
Answer
24/25.
Why not the others: '6/5' doubles sin(theta) instead of using the double-angle formula; '7/25' gives cos(2 theta); '4/5' gives cos(theta).
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