SOLUTION: 15. Solve for 0≤𝑥<2𝜋: cosx ∙ sinx = sin2x

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Question 1180238: 15. Solve for 0≤𝑥<2𝜋: cosx ∙ sinx = sin2x
Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


cos%28x%29%2Asin%28x%29=sin%282x%29

Use the double angle formula for sine on the right.

cos%28x%29%2Asin%28x%29=2sin%28x%29cos%28x%29

Collect like terms.

0+=+sin%28x%29%2Acox%28x%29

sin%28x%29=0 or cos%28x%29=0

ANSWER: 0, pi/2, pi, and 3pi/2