SOLUTION: how do you solve cos2(x)-sin^2(x)+ sin(x) + 1 = 0 ?

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Question 296467: how do you solve cos2(x)-sin^2(x)+ sin(x) + 1 = 0 ?
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
how do you solve cos^2(x)-sin^2(x)+ sin(x) + 1 = 0 ?
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Since cos^2(x) = 1-sin^2(x)
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1-sin^2(x) - sin^2(x) + sin(x) = 0
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-2sin^2(x)+sin(x)+1 = 0
2sin^2(x) - sin(x) -1 = 0
(2sin(x) + 1)(sin(x) -1) = 0
sin(x) = -1/2 or sin(x) = 1
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x = (7/6)pi or x = (11/12)pi or x = pi/2
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Cheers,
Stan H.