Cos2x+3sin^2x=1,25 помогите

Решение Cos2x+3sin^2x=1,25 1 - 2sin²x + 3sin²x = 1,25 sin²x = 1 - 1,25 sin²x = 0,25 sin²x = 1/4 1)  sinx = - 1/2 x = (-1)^n*arcsin(- 1/2) + πk, k ∈ Z x = (-1)^(n+1)*arcsin(1/2) + πk, k ∈ Z x = (-1)^(n+1)*(π/6) + πk, k ∈ Z 2)  sinx = 1/2 x₁ = (-1)^n*arcsin(1/2) + πn, n ∈ Z x₂ = (-1)^n*(π/6) + πn, n ∈ Z