Cos*(2p-3x)*cosx+sin3x*cos(3p/2+x) найдите х

Question

Cos*(2p-3x)*cosx+sin3x*cos(3p/2+x) найдите х

Answer 1

Решение
cos(2π - 3x)cosx + sin3xcos(3π/2 + x) = 0
cos3xcosx + sin3xsinx  = 0
cos(3x - x) = 0
cos2x = 0
2x = π/2 + πk, k∈Z
x = π/4 + πk/2, k∈Z