Question

2tgx/1+tg^2x=cosx помогите решить

Answer 1

Решение
2tgx/(1+tg²x) = cosx
2sinxcosx - cosx = 0
cosx(2sinx - 1) = 0
1)  cosx = 0 
x = π/2 + πk, k ∈ Z
2)  2sinx - 1 = 0
2sinx = 1
sinx = 1/2
x = (-1)^n arcsin(1/2) + πn, n ∈ Z
x = (-1)^n (π/6) + πn, n ∈ Z