int (4x)/(1-x^4)dx4x1x4dx =?

1 Answer

Notice that

4(x/(1-x^4))=2x/( (x^2+1))-1/( (x-1))-1/( (x+1))4(x1x4)=2x(x2+1)1(x1)1(x+1)

Hence

int x/(1-x^4)dx=2int x/( (x^2+1))dx-int1/( (x-1))dx-int1/( (x+1))dx=log(x^2+1)-log(x-1)-log(x+1)+c= log(x^2+1)-log(x^2-1)+cx1x4dx=2x(x2+1)dx1(x1)dx1(x+1)dx=log(x2+1)log(x1)log(x+1)+c=log(x2+1)log(x21)+c