1 Cos x 3 2cos x 0

$Solved Cos^2 (x) + 2cos (x) + 1 = 0 A) (2 pi) B){pi/4 7 | Chegg.com$

$Evaluate int0^xe | cos x | { 3cos ( 1/2cos x ) + 2sin ( 1/2cos x ) }sin ...$

$calculus - solving $0=-2\\sin(x) - 2\\cos(2x)$ - Mathematics Stack Exchange$