Integral 0 menuju phi/4 (sin 2x+2sin cos 3x) dx

jawab

0..π/4 ∫ (sin 2x + 2 sin x cos 3x)dx =
= (0..π/4) ∫ (sin 2x  + sin 4x - sin 2x] dx
= (0..π/4) ∫ sin 4x dx
= - 4 cos 4x ]π/4..0
= - 4 [cos π - cos  0]
= - 4(-1 - 1)
= -4(-2)
= 8