You want to show that with , , then the following equality holds :
Let us break this problem. Since and are relatively prime, the following must hold :
Remember that Fermat Little Theorem and Euler generalization I came up with in your previous topic ? This problem strikingly calls for it. Remember that for any with and , we have .
Thus, the following must hold (because and are relatively prime) :
Can you see how to finish the question by using (*) now ?