hasil dari integral cos

Int (cos^2 2x . sin 2x) dx
Misal : u = cos 2x => du = -2 sin 2x dx => sin 2x dx = -1/2 du
Int cos^2 2x . sin 2x dx
= Int u^2 . -1/2 du
= Int -1/2 u^2 du
= -1/2 . 1/3 u^3 + C
= -1/6 cos^3 2x + C