SOLUTION: What are the x's of: ((sin^2)x) +(cos)x) +1)) = 0

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Question 747131: What are the x's of: ((sin^2)x) +(cos)x) +1)) = 0
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
What are the x's of: ((sin^2)x) +(cos)x) +1)) = 0
sin%5E2%28x%29%2Bcos%28x%29%2B1=0
1-cos%5E2%28x%29%2Bcos%28x%29%2B1=0
-cos%5E2%28x%29%2Bcos%28x%29%2B2=0
cos%5E2%28x%29-cos%28x%29-2=0
(cos(x)-2)(cos(x)+1)=0
cos(x)=2 (reject,(-1 ≤ cosx ≤ 1)
cos(x)=-1
x=π