precal
posted by al on .
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solve. 2sin^(2)x=2+cosx

2 (1cos^2 x) = 2 + cos x
2  2 cos^2 x = 2 + cos x
cos x + 2 cos^2 x = 0
cos x ( 1 + 2 cos x) = 0
cos x = 0 > x = 90 degrees (pi/2 radians etc)
cos x = 1/2 > x = 120 degrees, 240 degrees etc