Question 241424: Cos(x) + 2 = -sec(x)
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Cos(x) + 2 = -sec(x)
cos(x) + sec(x) + 2 = 0
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Multiply thru by cos(x) to get this quadratic:
cos^2(x) + 1 + 2cos(x) = 0
Rearrange:
cos^2(x) + 2cos(x) + 1 = 0
Factor:
(cos(x) + 1)^2 = 0
cos(x) = -1
x = pi+2npi where n = 0,1,2,...
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Cheers,
Stan H.
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