3sin2x-4sinx*cosx+cos2x=0
3sin2x - 4sinxcosx + cos2x = 0 3sin2x - 2sin2x + cos2x = 0 sin2x + cos2x=0 |:cos2x tg2x + 1 = 0 tg2x = -1 2x = -π/4 + πk,k ∈ Z x = -π/8 + πk/2, k ∈ Z