Решить уравнение sin7x+cos4x=sinx

sin7x - sinx + cos4x = 0;2sin3x · cos4x + cos4x = 0;cos4x(2sin3x + 1) = 0;1) cos4x = 0;4x = π/2 + πn;x = π/8 + πn/4, n∈Z;2) 2sin3x + 1 = 0;sin3x = -1/2;3x = (-1)^(k) · π/6 + πk;x = (-1)^(k) · π/18 + πk/3, k∈Z;Ответ:x = π/8 + πn/4, n∈Z; x = (-1)^(k) · π/18 + πk/3, k∈Z;