# Mod 5

• Oct 5th 2011, 12:08 PM
dwsmith
Mod 5
How do I show that this (see below) has no solutions?

$2+b^3\equiv b \ (\text{mod} \ 5)$
• Oct 5th 2011, 12:19 PM
TheEmptySet
Re: Mod 5
Quote:

Originally Posted by dwsmith
How do I show that this (see below) has no solutions?

$2+b^3\equiv b \ (\text{mod} \ 5)$

Just use every possiblity. b=0,1,2,3,4 and show none of them make the equation true!
• Oct 5th 2011, 12:34 PM
dwsmith
Re: Mod 5
Quote:

Originally Posted by TheEmptySet
Just use every possiblity. b=0,1,2,3,4 and show none of them make the equation true!

I was hoping for a clearing way.