Core 3: Find all the solutions of 2cos(2x) = 1-2sin(x) in the interval 0<x<360

2cos(2x) = 1-2sin(x)

2(1-2sin²(x)) = 1-2sin(x) -- by our trigonometric functions

2-4sin²(x) = 1-2sin(x)

4sin²(x)-2sin(x)-1=0 -- rearrange

sin(x) = (2±(4-4(4)(-1))^0.5)/8 -- quadratic formula

x = 54 & x = -18 which on the range 0