SOLUTION: what values for θ (0≤θ≤2π)satisfy the equation 2 cosθ+1=- cos θ.

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Question 755347: what values for θ (0≤θ≤2π)satisfy the equation 2 cosθ+1=- cos θ.
Answer by Cromlix(4381) About Me  (Show Source):
You can put this solution on YOUR website!
2 cosθ+1=- cos θ.
2 cos theta + 1 + cos theta = 0
3 cos theta + 1 = 0
3 cos theta = -1
cos theta = -1/3
Cos is negative in the second
and third quadrants
theta = 1.9 and 4.4 radians
Hope this helps
:-)