Hints for Homework 9
6.12: Use Theorem 6.5.
6.17: Remember that because r is in U(n), there is a multiplicative
inverse mod n. Use this fact to show one-to-one and onto.
6.29: This follows from Cayley's Theorem, but be sure to give
a clear explanation.
7.2: Use Lagrange's Theorem, second part.