SOLUTION: solve each equation 19) 1 + sin theta = 2cos^2 theta

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Question 712340: solve each equation
19) 1 + sin theta = 2cos^2 theta
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
1 + sin theta = 2cos^2 theta
1+sinx = 2cos^2x
1+sinx = 2(1-sin^2x
1+sinx = 2-2sin^2x
2sin^2x+sinx-1=0
(2sinx-1)(sinx+1)
2sinx-1=0
sinx=1/2
x=π/6, 5π/6 (in quadrants I and II where sin>0)