# Quotient Ring of Integers and Zero

## Theorem

Let $\struct {\Z, +, \times}$ be the integral domain of integers.

Let $\ideal 0$ be the principal ideal of $\struct {\Z, +, \times}$ generated by $0$.

The quotient ring $\struct {\Z / \ideal 0, +, \times}$ is isomorphic to $\struct {\Z, +, \times}$.

## Proof

 $\displaystyle \ideal 0$ $=$ $\displaystyle \set {\sum^n_{i \mathop = 1} r_i \times 0 \times s_i: n \in \N; r_i, s_i \in \Z}$ Definition of Principal Ideal of Ring $\displaystyle$ $=$ $\displaystyle \set {\sum^n_{i \mathop = 1} 0: n \in \N}$ $0$ is the zero under integer multiplication $\displaystyle$ $=$ $\displaystyle \set 0$ Integer Addition Identity is Zero