integral dari sin 4x cos 2x

integral trigonometri

∫ sin 4x cos 2x dx = ∫ 1/2 (2 sin 4x cos 2x) dx
=1/2 ∫ sin 1/2(4x+2x) + sin 1/2(4x-2x) dx
= 1/2 ∫ sin 3x + sin x dx
= 1/2[.-1/3 cos 3x - cos x] + c
= - 1/6 cos 3x - 1/2 cos x + c