I am trying to do some integrals and it seems that there is a problem !!
I have tried to add some assumptions but still not working.
If you have seen this kind of problems, please contact me.( running mode don't stop even after hours and no error message)
I would try polar coordinates. Your assumptions are a little strange: you integrate on z from -Infinity to +Infinity, but you assume z>=0.
Thank you for your reply.
the assumptions on z is a mistake, i have put assumptions on z^2 but forgot to suppress it all... thank you for the remark. But still don't work. I will try with polar coordinates .