- #1

jgens

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## Homework Statement

Let [itex]R[/itex] be a commutative ring with [itex]1[/itex]. What are the units of [itex]M_n(R)[/itex]?

## Homework Equations

N/A

## The Attempt at a Solution

If [itex]R[/itex] is a field, then I know that we can characterize the units as those matrices with non-zero determinant (since those are the invertible matrices). But since [itex]R[/itex] is not even an integral domain necessarily, I could use some help. Is there any nice way to characterize the units?