# Multiplicative Inverse proof

1. Sep 23, 2010

### kathrynag

1. The problem statement, all variables and given/known data
Show that if and [c] are multiplicative inverses of [a] in $$Z_{n}$$, then b$$\equiv$$c mod n.

2. Relevant equations

3. The attempt at a solution
I'm totally confused on this.

2. Sep 23, 2010

### kathrynag

[a]=1 and [a][c]=1, right?