If f=x1+x2+13(x1+x2)3+15(x1+x2)5+... to ∞ and g=x−23x3+15x5+17x7−29x9+..., then f=d×g. Find 4d.
1)∫x3+3x+4√xdx
2)∫√x(3x2+2x+3)dx
3)∫(2x2−3sinx+5√x)dx
4) ∫sec2xcsc2xdx