Question

find solutions for cos(2x)=4 cos x-2

Answer 1

the 1st one is 1/2d to the 2 power fin to the 2 e2 u

Answer 2

could you break it down?

Answer 3

x=12d2fin2e2U

Answer 4

x=1/2d2fin2e2U

Answer 5

sorry i need solutions from 0 to 2pi. so in radians

Answer 6

2cos^2 x -1 = 4cos x - 2. Call x = cos x
2x^2 - 4x + 1 = 0 . quadratic equation with 2 real roots
x1 = 1 + V2/2 (rejected as > 1), and x2 = 2 - V2/2 = 0.293
cos x = x2 = 0.293 = cos A
x = A or x = -A. (check)