# Ring

• August 18th 2012, 08:23 PM
mathrld
Ring
Is $\{bi: b \in \mathbb{Z}\}$ where $i^2=-1$ a ring?
I am assuming it isnt since (bi)*(ci)=-bc where b and c are elements of Z
• August 18th 2012, 08:35 PM
Deveno
Re: Ring
that is correct, the set is not closed under multiplication.
• August 18th 2012, 08:52 PM
mathrld
Re: Ring
Thanks :)))))