Math 2.0

definition

Integral domain

Definition

An integral domain is a commutative ring RR with these two properties.

  1. 1≠01 \neq 0 in RR.
  2. For all a,b∈Ra, b \in R, if ab=0a b = 0, then a=0a = 0 or b=0b = 0.

Equivalently, RR is a nonzero commutative ring in which 00 is the only zero divisor.

Remarks

The integers Z\mathbb{Z} and every field are integral domains. The ring Z/6Z\mathbb{Z}/6\mathbb{Z} is not an integral domain, because 2⋅3=02 \cdot 3 = 0. In an integral domain, cancellation holds for nonzero factors. Some authors, and Mathlib, also use the word domain for a noncommutative ring with property 2.

Explanations

L1 human

An integral domain is a ring that behaves like the integers for products. If a product is zero, then one of the factors is zero. This is what you use when you solve (x−2)(x−3)=0(x - 2)(x - 3) = 0.

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  1. Group concept
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Sources

  1. Web https://en.wikipedia.org/wiki/Integral_domain, Definition