Cos6x=1/2 помогите плиз

Question

Cos6x=1/2 помогите плиз

Answer 1

Cos 6x = 1/2
1) 6x = +π/3 + 2πk → x1 = π/18 + πk/3 
2) 6x = -π/3 + 2πk → x2 = -π/18 + πk/3 
Ответ: х = +-π/18 + πk/3  (k ∈Z)