# Solving a quadruple integral of view factor

I'm solving an analytical quadruple integral in Mathematica, but the app can't solve it. I don't know if it is because that I do a bad formulation of the integral or maybe, Mathematica is not able to do this.

I divided the quadruple integral into two double integrals. So actually, Mathematica solves the first double integral, but when I put the result into the second, the app doesn't solve it.

I don't know how to write the integrals here, that's why I attached a photo.

• I have tried indefinite integral with Integrate and the 3rd-party RubiInt, both of which are successful. – Αλέξανδρος Ζεγγ Jul 31 at 6:54
• You do not need actually the 4-integral. The 2-integral you typed is sufficient. Just do the substitution $a=x-u$, $b=x+u$ in the original integral. The integration over $b$ is trivial. Analogically you do with $y$ and $v$ variables. – yarchik Jul 31 at 7:34
• Welcome to Mathematica.SE! I suggest the following: 1) As you receive help, try to give it too, by answering questions in your area of expertise. 2) Take the tour! 3) When you see good questions and answers, vote them up by clicking the gray triangles, because the credibility of the system is based on the reputation gained by users sharing their knowledge. Also, please remember to accept the answer, if any, that solves your problem, by clicking the checkmark sign! – Michael E2 Jul 31 at 15:13
• Thank you for the answers. I'm running with Rubi, but I'm not having good luck. I'm new in mathematica. On the other hand, I don't understand the cv that you made it, you mean in the 4-integral? – Mijail Aug 1 at 4:52