Consider a binary operation # that is closed under the set of integers (if a and b are integers, then a#b is an integer).

Assume that, for all integers a and b, it is true that (a#b)#a=b.

Prove that a#(b#a)=b.

(In reply to re(6): A simple solution by SilverKnight)

I know what the property of inverses states. My point is, you can't assume it, because it's what you are proving.

Posted by DJ on 2003-10-20 11:59:28