SOLUTION: How do I find the possible angles for theta if the equation is cos theta=sin (theta/2)?

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Question 756234: How do I find the possible angles for theta if the equation is cos theta=sin (theta/2)?
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
How do I find the possible angles for theta if the equation is
cos theta=sin (theta/2)
cosx=sin(x/2)
cos%28x%29=sqrt%28%281-cos%28x%29%29%2F2%29
square both sides
cos%5E2%28x%29=+%281-cos%28x%29%29%2F2%29
2cos%5E2%28x%29=1-cos%28x%29
2cos%5E2%28x%29%2Bcos%28x%29-1=0
(2cos(x)-1)(cos(x)+1)=0
2cos(x)-1=0
cos(x)=1/2
x=π/3+2πn, 5π/3+2πn, n=integer
or
cos(x)+1=0
cos(x)=-1
x=π+2πn, n=integer