If sin(theta) + cos(theta) = 1, what is the value of sin(2*theta)?
Answer and explanation
Correct answer: B. 0
- Step 1: Square both sides: (sin theta + cos theta)^2 = 1^2. Step 2. sin^2 theta + cos^2 theta + 2 sin theta cos theta = 1. Step 3. 1 + sin(2 theta) = 1 => sin(2 theta) = 0. Answer: 0. Why not the others: 1 occurs when (sin + cos)^2 = 2.
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