Cos²x+cosx=sin²x помогите плиз))

Question

Cos²x+cosx=sin²x помогите плиз))

Answer 1

Cos²x + cosx = sin²x
cos²x - sin²x + cosx =0
cos2x + cosx =0

2cos(3x/2) cos(x/2) = 0

3x/2 = π/2 + πn, n ∈ Z
3x=π+2πn, n ∈ Z
x=π/3 + 2πn/3, n ∈ Z

cos (x/2) = 0
x/2 = π/2 + πn, n ∈ Z
x=π + 2πn,n ∈ Z