Интеграл от cos^3 x *sin 2x по dx
cos^3 x *sin 2x=2cos^3 x*cos x*sin x=2cos^4 x *sin x
Integral 2cos^4 x *sin x dx=
= 2 integral sin(x) cos^4(x) dx
t = cos(x) , dt = -sin(x) dx:
= -2 integral t^4 dt
= -(2 t^5)/5+C
t = cos(x):
= -2/5 cos^5(x)+C