Hello out there! I'm a new guy here, so don't pick on me too much...I cry easy(adsbygoogle = window.adsbygoogle || []).push({});

I want to show that a set of units in a ring forms a group under multiplication. What steps would I take to show this?

Things that my feable brain knows:

1) if [tex]a[/tex] is a unit, it is invertible and [tex]a^-^1[/tex] is also a unit.

2) the product of units is a unit.

3) and that [tex](ab)^-^1 = b^-^1 a^-^1[/tex]

How should I proceed?

Thanks in advance for any and all help.

Best!

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# Set of units forming a group

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