Тригонометрические уравнения а) 37cos x + 5sin^2 x + 5cos^2 x=4 б) cos^2 2x/37=3/4

А) 37cosx + 5sin²x + 5cos²x = 4
37cosx + 5 = 4
37cosx = -1
cosx = -1/37
x = ±arccos(-1/37) + 2πn, n ∈ Z

cos²(2x/37) = 3/4
cos(2x/37) = ±√3/2

cos(2x/37) = √3/2
2x/37 = ±π/6 + 2πn, n ∈ Z
x = ±37π/12 + 37πn, n ∈ Z

cos(2x/37) = -√3/2
2x/37 = ±5π/6 + 2πn, n ∈ Z
x = ±185π/3 + 37πn, n ∈ Z.