SOLUTION: Solve the equation on the interval 0 < theta < 2pi cos^2 theta-sin^2 theta+sin theta=0

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Question 525248: Solve the equation on the interval 0 < theta < 2pi
cos^2 theta-sin^2 theta+sin theta=0
Answer by tarungehlot(9) About Me  (Show Source):
You can put this solution on YOUR website!
let theta = @
cos ^2 @ - sin ^2 @ + sin @=0
now
cos ^2 @ = 1- 2sin ^2 @
1 - sin ^2 @ - sin ^2 @ + sin @=0
-2 sin ^2 @ +sin @ +1=0
(2sin @ -1)(sin @ +1)=0
hence
@= pie/6( in first and second quadrant ) and @ = - pie /2 ( in 3 and 4 quadrant)