Let R be a commutative ring with unity and let U(R) denote
Chapter 12, Problem 22E(choose chapter or problem)
Let R be a commutative ring with unity and let U(R) denote the set of units of R. Prove that U(R) is a group under the multiplication of R. (This group is called the group of units of R.)
Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.
Becoming a subscriber
Or look for another answer