SOLUTION: Find all values of θ in the interval of [0°,360°) that satisfy the equation 2sin^2(θ/2)=cosθ.

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Question 760338: Find all values of θ in the interval of [0°,360°) that satisfy the equation 2sin^2(θ/2)=cosθ.
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
Find all values of θ in the interval of [0°,360°) that satisfy the equation 2sin^2(θ/2)=cosθ.
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2sin%5E2%28x%2F2%29=cos%28x%29
sin%28x%2F2%29=sqrt%28%281-cos%28x%29%29%2F2%29
sin%5E2%28x%2F2%29=%28%281-cos%28x%29%29%2F2%29
1-cos(x)=cos(x)
2cos(x)=1
cos(x)=1/2
x=60º, 300º (in Q1 and Q4 where cos>0)