Identity function: Difference between revisions

From Citizendium
Jump to navigation Jump to search
imported>Richard Pinch
(New entry, just a stub)
 
mNo edit summary
 
(One intermediate revision by one other user not shown)
Line 1: Line 1:
{{subpages}}
In [[mathematics]], the '''identity function''' on a set ''X'' is the [[function (mathematics)|function]] from ''X'' to itself which maps each element to itself:
In [[mathematics]], the '''identity function''' on a set ''X'' is the [[function (mathematics)|function]] from ''X'' to itself which maps each element to itself:


:<math>\mbox{id}_X : x \mapsto x .\,</math>
:<math>\mbox{id}_X : x \mapsto x .\,</math>


The identity function is [[invertible function|invertible]] (and is its own [[inverse function]]).  It is a [[permutation]] of the set, and is the [[identity element]] of the [[symmetric group]] on ''X''.
The identity function is [[invertible function|invertible]] (and is its own [[inverse function]]).  It is a [[permutation]] of the set, and is the [[identity element]] of the [[symmetric group]] on ''X''.[[Category:Suggestion Bot Tag]]

Latest revision as of 06:01, 31 August 2024

This article is a stub and thus not approved.
Main Article
Discussion
Related Articles  [?]
Bibliography  [?]
External Links  [?]
Citable Version  [?]
 
This editable Main Article is under development and subject to a disclaimer.

In mathematics, the identity function on a set X is the function from X to itself which maps each element to itself:

The identity function is invertible (and is its own inverse function). It is a permutation of the set, and is the identity element of the symmetric group on X.