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The element 0 is usually referred to as the identity element and if it exists, it is unique
27:
In mathematics, a function that always returns the same value that was used as its argument
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to be this identity element. Such a definition generalizes to the concept of an
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49:
17:
637:
407:
264:
737:. Mathematical Association of America Textbooks. Mathematical Assn of Amer.
233:
473:
469:
153:
450:
41:
351:
784:
A First Course in
Topology: An Introduction to Mathematical Thinking
614:...then the diagonal set determined by M is the identity relation...
40:
808:
Conferences, University of
Michigan Engineering Summer (1968).
816:
we see that an identity element of a semigroup is idempotent.
373:, one can alternately define the identity function on
267:, where a function is defined as a particular kind of
602:. American Mathematical Society. 1974. p. 92.
79:that always returns the value that was used as its
457:(essentially multiplication by 1), considered in
712:. Undergraduate Texts in Mathematics. Springer.
693:Elementary Linear Algebra (Applications Version)
576:(11th ed.). Sarat Book House. p. 36.
811:Foundations of Information Systems Engineering
661:Rosales, J. C.; García-Sánchez, P. A. (1999).
484:containing only this isometry (symmetry type
8:
428:the identity function is represented by the
733:D. Marshall; E. Odell; M. Starbird (2007).
599:Proceedings of Symposia in Pure Mathematics
709:Applied Linear Algebra and Matrix Analysis
369:Since the identity element of a monoid is
271:, the identity function is given by the
204:is always the same as the input element
540:
664:Finitely Generated Commutative Monoids
468:the identity function is trivially an
449:The identity function on the positive
7:
787:. Courier Corporation. p. 65.
695:(9th ed.), Wiley International
572:Mapa, Sadhan Kumar (7 April 2014).
187:In other words, the function value
574:Higher Algebra Abstract and Linear
498:, the identity function is always
455:completely multiplicative function
25:
781:Conover, Robert A. (2014-05-21).
142:is defined to be a function with
48:of the identity function on the
667:. Nova Publishers. p. 1.
366:(under function composition).
87:is the identity function, the
1:
735:Number Theory through Inquiry
172: for all elements
844:Basic concepts in set theory
406:The identity function is a
216:. The identity function on
83:, unchanged. That is, when
870:
548:Knapp, Anthony W. (2006),
228:(its codomain is also its
104:is true for all values of
29:
638:10.1007/978-3-319-31159-3
505:The identity function is
472:. An object without any
130:, the identity function
30:Not to be confused with
397:need not be functions.
73:identity transformation
839:Elementary mathematics
834:Functions and mappings
691:Anton, Howard (2005),
354:of all functions from
307:is any function, then
239:The identity function
52:
706:T. S. Shores (2007).
446:chosen for the space.
44:
442:, regardless of the
335:function composition
333:, where "∘" denotes
289:Algebraic properties
251:is often denoted by
762:Hyperbolic Geometry
626:Nel, Louis (2016).
226:surjective function
849:Types of functions
530:Indicator function
222:injective function
53:
794:978-0-486-78001-6
764:, Springer 2005,
758:James W. Anderson
719:978-038-733-195-9
674:978-1-56072-670-8
647:978-3-319-31159-3
629:Continuity Theory
609:978-0-8218-1425-3
583:978-93-80663-24-1
559:978-0-8176-3248-9
496:topological space
381:identity morphism
337:. In particular,
273:identity relation
65:identity relation
63:, also called an
61:identity function
16:(Redirected from
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18:Identity mapping
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520:Identity matrix
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408:linear operator
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744:978-0883857519
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632:. p. 21.
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36:Empty function
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2:
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770:1-85233-934-9
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550:Basic algebra
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525:Inclusion map
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482:trivial group
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459:number theory
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412:vector spaces
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224:as well as a
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156:, satisfying
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32:Null function
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552:, Springer,
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466:metric space
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426:vector space
393:
387:, where the
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69:identity map
68:
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60:
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50:real numbers
476:has as its
423:dimensional
57:mathematics
854:1 (number)
828:Categories
536:References
507:idempotent
500:continuous
401:Properties
265:set theory
116:Definition
234:bijective
108:to which
514:See also
474:symmetry
470:isometry
451:integers
298: :
277:diagonal
154:codomain
89:equality
81:argument
77:function
350:of the
346:is the
148:as its
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671:
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417:In an
371:unique
352:monoid
150:domain
494:In a
464:In a
453:is a
444:basis
275:, or
230:range
126:is a
59:, an
46:Graph
789:ISBN
766:ISBN
739:ISBN
714:ISBN
669:ISBN
642:ISBN
604:ISBN
578:ISBN
554:ISBN
480:the
322:= id
312:∘ id
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634:doi
391:of
383:in
360:to
293:If
279:of
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136:on
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71:or
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339:id
328:∘
318:=
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438:n
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