математика 2. sin2x*cos8x=-sinx*cs11x

sin(2x)cos(8x) = -sin(x)cos(11x)

(-sin(6x) + sin(10x))/2 = (sin(10x) - sin(12x))/2

-sin(6x) + sin(10x) = sin(10x) - sin(12x)

sin(12x) = sin(6x)

2sin(6x)cos(6x) = sin(6x)

sin(6x) = 0 --> x = πk/6

2cos(6x) = 1

cos(6x) = 1/2

x = ±π/18 + πk/3

Ответ: πk/6; ±π/18 + πk/3, k - целое.