SOLUTION: Could someone show me what to do in order to: Solve for Theta on the interval 0 < or = to theta < or = to 360: cos^2 theta- 3 cos theta = 4

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Question 756765: Could someone show me what to do in order to:
Solve for Theta on the interval 0 < or = to theta < or = to 360:
cos^2 theta- 3 cos theta = 4

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Solve for Theta on the interval 0 < or = to theta < or = to 360:
cos^2 theta- 3 cos theta = 4
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Solve for Theta on the interval 0 <= theta <= 360:
cos^2 theta- 3 cos theta = 4
cos^2 - 3 cos - 4 = 0
(cos - 4)*(cos + 1) = 0
cos = 4 (no real numuber solution)
cos = -1
theta = 180 degs