I have a function
f of four variables.
x22 like this
f = (-(x1 - x11)^4 - 6 (x1 - x11)^2 (x2 - x22)^2 + 3 (x2 - x22)^4)/( 4 Pi ((x1 - x11)^2 + (x2 - x22)^2)^3);
I want to calculate the indefinite integral, but it seems that order of integration in this particular case matters.
If I try with two different orders of integration, i get different results:
Case 1 :
FullSimplify@Integrate[f, x1, x2, x11, x22]
Case 2 :
FullSimplify@Integrate[f, x22, x11, x2, x1]
I taught that order of integration in indefinite integrals does not matter. How should this problem be tackled?
This is the problem that I'm trying to figure out. I don't understand how were these functions integrated.