Решите уравнение
sin^2(x/6)-cos^2(x/6)=1/2

sin²(x/6) - cos²(x/6) = 1/2

-cos(2*x/6) = 1/2

cos(x/3) = -1/2

x/3 = ±2π/3 + 2πn, n ∈ Z

x = ±2π + 6πn , n ∈ Z