2sinxcosx = 2sinx -cosx + 1
2sinxcosx - 2sinx + cosx - 1 = 0
2sinx(cosx - 1) + (cos x - 1) = 0
(cosx - 1)(2sinx + 1) = 0
cosx - 1 = 0 или 2sinx + 1 = 0
1) cos x = 1
x = 2pi*n
2) 2sinx = -1
sinx = -1/2
x = (-1)^k+1*pi/6 + pi*k
Ответ. x = 2pi*n , x = (-1)^k+1*pi/6 + pi*k