∫f(x) dx = x^2.sinxf(x) = x^2.cosx +2x.sinx∫f(x)/x dx=∫ (xcosx + 2sinx ) dx=∫ xdsinx - 2cosx =xsinx -∫ sinx dx -2cosx =xsinx +cosx -2cosx +C=xsinx -cosx +C