sin^2x+sin^24x=1
(1 — cos(2x)) / 2 + (1 — cos(8x)) / 2 = 1
1 — cos(2x) + 1 — cos(8x) = 2
cos(2x) + cos(8x) = 0
2 * cos(5x) * cos(-3x) = 0
cos(5x) = 0 cos(3x) = 0
5x = пи/2 + пи * n 3x = пи/2 + пи * n
x = пи/10 + пи * n /5 x = пи/6 + пи *n /3