Given that theta is acute and sin(theta) = 35/37, find sin(2 theta).
Answer and explanation
Correct answer: B. 840/1369
- Step 1: Since theta is acute, cos(theta) = sqrt(1 - sin^2(theta)) = 12/37.
- Step 2: sin(2 theta) = 2 sin(theta) cos(theta) = 2 x 35/37 x 12/37 = 840/1369.
Answer
840/1369.
Why not the others: '1225/1369' squares sin(theta) instead of using the double-angle formula; '12/37' gives cos(theta); '35/37' gives sin(theta) itself.
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