помогите решить

1 - cos 8x = sin 4x

sin^2 4x + cos^2 4x - (cos^2 4x - sin^2 4x) = sin 4x

sin^2 4x + cos^2 4x - cos^2 4x + sin^2 4x=sin 4x

2sin^2 4x - sin 4x=0

sin 4x (2sin 4x-1) = 0

sin 4x = 0 sin 4x=1/2

4x=πn, n∈ Z 4x = (-1) ^k * π/6 + πk, k∈ Z

x = πn/4, n∈ Z x = ((-1) ^k*π) / 24 + πk/4, k∈ Z