1. The problem statement, all variables and given/known data [tex]a+b = ab = a^b[/tex] Prove that [tex]a=b=2[/tex] 2. Relevant equations 3. The attempt at a solution Ok, I've tried this for more than an hour now, but can't figure out how to do it. I guess it could be done with Lambert's W-function (?) but this task is given on a much lower level. They haven't even learned how to prove that when x is a odd number, then x squared must be odd aswell. So this must be really simple, but still I can't figure anything out. I've tried to take the equations and isolate a or b, and then insert it into one of the other functions, but I've gotten nowhere. I really hope someone could help me se the obvious here.