Modulo arthmetic solve for x^N..... Hay all, I am stuck on a problem, and its driving me crazy. I have a problem, xN = a mod b. Where I have to solve for x. My first thought was use to Fermat's little theorem(if I have the name correct), however my b is not a prime, (neither is 'N' or 'a' for that fact). I can give the exact problem with numbers if needed, but thought it would be slightly easier with variables instead. Any tips on how I could start to solve this would be great. Any questions please ask.