А) 2sinxcosx + sinx -2cosx -1 = 0
(2sinxcosx - 2cosx) + (sinx-1)=0
2cosx(sinx-1) + (sinx-1)=0
(sinx-1)(2cosx+1)=0
sinx-1=0 или 2cosx+1 = 0
sinx = 1 cosx=-
x = π/2 + 2πk, k∈Z x= +- (π-arccos )+ 2πn, n∈Z
x= +- 2π/3 + 2πn
б) -3π/2, π/2, -4π/3, -2π/3, 4π/3