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August 1, 2014

August 1, 2014

Posted by **Lindsey** on Tuesday, January 17, 2012 at 7:40pm.

sin^2x + cosx + 1 = 0

- Trigonometry -
**Damon**, Tuesday, January 17, 2012 at 8:04pm(1-cos^2 x) + cos x + 1 = 0

- cos^2 x + cos x + 2 = 0

cos^2 x - cos x - 2 = 0

(cos x - 2)(cos x + 1) = 0

cos x = 2 impossible, out of range

so

cos x = -1

pi

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