(adsbygoogle = window.adsbygoogle || []).push({}); [SOLVED] ring theory problem

1. The problem statement, all variables and given/known data

True or false. The product of two nonunits in Z_n may be a unit.

2. Relevant equations

3. The attempt at a solution

If a and b are two non units in Z_n, and ab <= n, then the result is clear, since ab would not be relatively prime to n. But what about if ab > n ?

Obviously the units form a group under multiplication, but I don't see how that helps.

**Physics Forums | Science Articles, Homework Help, Discussion**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Homework Help: Ring theory problem

**Physics Forums | Science Articles, Homework Help, Discussion**