Sinx•sin (60-x) sin• (60+x) = 0,125

Если в градусах, то: sin (60-x) = sin (π/3-x) = sin (π/3) * cos (x) - cos (π/3) * sin (x)

sin (60+x) = sin (π/3+x) = sin (π/3) * cos (x) + cos (π/3) sin (x)

sin (x) * (sin (π/3) * cos (x) - cos (π/3) sin (x)) * (sin (π/3) * cos (x) + cos (π/3) sin (x)) = 0,125

sin (x) * (((√3) / 2) * cos (x) - sin (x) / 2) * (((√3) / 2) * cos (x) + sin (x) / 2) = sin (x) * (3cos²x/4-sin²x/4) ;

(3sin (x) cos²x) / 4-sin³x/4=0,125

3sin (x) cos²x-sin³x=0,5

3sin (x) * (1-sin²x) - sin³x=0,5

3sin (x) - 3sin³x-sin³x=0,5

3sin (x) - 4sin³x=0,5