sin3x-sinx+2cos^2x=1
2 * sin((3x — x) / 2) * cos((3x + x)/2) + 2 * cos^2(x) = sin^2(x) + cos^2(x)
2 * sin(x) * cos(2x) + (cos^2(x) — sin^2(x)) = 0
2 * sin(x) * cos(2x) + cos(2x) = 0
cos(2x) * (2 * sin(x) + 1) = 0
cos(2x) = 0 2 * sin(x) + 1 = 0
2x = пи/2 + пи * n sin(x) = -1/2
x = пи/4 + пи * n/2 x = (-1)^(n+1) * пи/6 + пи * n
n — целое n — целое