2cos 2х-3 sin x cos x + sin2x =0

Question

2cos 2х-3 sin x cos x + sin2x =0

Answer 1

Ну-с допустим, что 3 = 1.5*2
Тогда

2cos2x -1.5*2sinxcos+sin2x = 0
2cos2x - 1.5sin2x + sinx = 0

2cos2x - 0.5sin2x = 0 | :sin2x

2ctg2x - 0.5 = 0

ctg2x = 0.25
2x = arcctg 1/4 + π*n, n ∈ Z

x  = 0.5arcctg 1/4 + 0.5π*n, n ∈ Z