Prime ideal: Difference between revisions

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===Symbol-free definition===
===Symbol-free definition===


An [[ideal]] in a [[commutative unital ring]] (or in any [[commutative ring]]) is termed a '''prime ideal''' if it satisfies the following equivalent conditions:
An [[ideal]] in a [[commutative unital ring]]is termed a '''prime ideal''' if it satisfies the following equivalent conditions:


* Whenever the product of two elements in the ring lies inside that ideal, at least one of the elements must lie inside that ideal.
* Whenever the product of two elements in the ring lies inside that ideal, at least one of the elements must lie inside that ideal.
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An [[ideal]] <math>I</math> in a [[commutative unital ring]] <math>R</math> is termed a '''prime ideal''' if whenever <math>a, b \in R</math> are such that <math>ab \in I</math> then either <math>a \in I</math> or <math>b \in I</math>.
An [[ideal]] <math>I</math> in a [[commutative unital ring]] <math>R</math> is termed a '''prime ideal''' if whenever <math>a, b \in R</math> are such that <math>ab \in I</math> then either <math>a \in I</math> or <math>b \in I</math>.
==Definition for non-commutative rings==
The definition has many different forms for noncommutative rings:
* [[Prime ideal (noncommutative rings)]]
* [[Completely prime ideal]]

Revision as of 17:05, 17 December 2007

This article defines a property of an ideal in a commutative unital ring |View other properties of ideals in commutative unital rings

This property of an ideal in a ring is equivalent to the property of the quotient ring being a/an: integral domain | View other quotient-determined properties of ideals in commutative unital rings

Definition for commutative rings

Symbol-free definition

An ideal in a commutative unital ringis termed a prime ideal if it satisfies the following equivalent conditions:

  • Whenever the product of two elements in the ring lies inside that ideal, at least one of the elements must lie inside that ideal.
  • It is an ideal whose complement is a saturated subset (that is, is clsoed with respect to the operation of multiplication).
  • The quotient ring by that ideal is an integral domain

Definition with symbols

An ideal I in a commutative unital ring R is termed a prime ideal if whenever a,bR are such that abI then either aI or bI.