Jawabanmu

2014-08-17T14:44:04+07:00
Int - ( 1/2 cos(3x+2x) - 1/2 cos(3x-2x) )
- int ( 1/2 cos 5x - 1/2 cos x )
- ( 1/10 sin5x - 1/2 sinx ) +c
-1/10 sin5x + 1/2 sinx + c
2014-08-17T14:45:44+07:00
Sin x sin y =  \frac{1}{2} [ cos (x-y) - cos (x+y) ]

= integral  \frac{1}{2} [ cos (x) - cos (5x) ] dx
=  \frac{1}{2} integral cos x - cos 5x dx
=  \frac{1}{2} [ sin x -  \frac{1}{5} cos 5x]