∭_(-1,0,0)^(1,2π,√(1-z^2 ))▒(r drdѲdz)/√(r^2+(〖z-zinitial)〗^2 )
First of all, you'll get more help if we could actually read what you were trying to do. Is this it?
Second, what have you tried?
Third, judging by the limits of your integral, I expect you made a mistake setting it up. Would you please post the ENTIRE problem so that we can help you further.