SOLUTION: Solve the following equation on the interval [0, 2pi] cos^2 x + 2 cos x + 1 = 0

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Question 962699: Solve the following equation on the interval [0, 2pi]
cos^2 x + 2 cos x + 1 = 0
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The left side expression is a perfect square trinomial, and therefor factorable, so you can finally use Zero Product Rule.