Injective function

Injective function

In mathematics, an injective function (also known as injection, or one-to-one function) is a function f that maps distinct elements of its domain to distinct elements; that is, f(x1) = f(x2) implies x1 = x2. (Equivalently, x1 ≠ x2 implies f(x1) ≠ f(x2) in the equivalent contrapositive statement.) In other words, every element of the function's codomain is the image of at most one element of its domain. The term one-to-one function must not be confused with one-to-one correspondence that refers to bijective functions, which are functions such that each element in the codomain is an image of exactly one element in the domain.

Comment
enIn mathematics, an injective function (also known as injection, or one-to-one function) is a function f that maps distinct elements of its domain to distinct elements; that is, f(x1) = f(x2) implies x1 = x2. (Equivalently, x1 ≠ x2 implies f(x1) ≠ f(x2) in the equivalent contrapositive statement.) In other words, every element of the function's codomain is the image of at most one element of its domain. The term one-to-one function must not be confused with one-to-one correspondence that refers to bijective functions, which are functions such that each element in the codomain is an image of exactly one element in the domain.
Depiction
Bijection.svg
Injection.svg
Injective composition2.svg
Injective function.svg
Non-injective function1.svg
Non-injective function2.svg
Not-Injection-Surjection.svg
Surjection.svg
Has abstract
enIn mathematics, an injective function (also known as injection, or one-to-one function) is a function f that maps distinct elements of its domain to distinct elements; that is, f(x1) = f(x2) implies x1 = x2. (Equivalently, x1 ≠ x2 implies f(x1) ≠ f(x2) in the equivalent contrapositive statement.) In other words, every element of the function's codomain is the image of at most one element of its domain. The term one-to-one function must not be confused with one-to-one correspondence that refers to bijective functions, which are functions such that each element in the codomain is an image of exactly one element in the domain. A homomorphism between algebraic structures is a function that is compatible with the operations of the structures. For all common algebraic structures, and, in particular for vector spaces, an injective homomorphism is also called a monomorphism. However, in the more general context of category theory, the definition of a monomorphism differs from that of an injective homomorphism. This is thus a theorem that they are equivalent for algebraic structures; see Homomorphism § Monomorphism for more details. A function that is not injective is sometimes called many-to-one.
Hypernym
Function
Is primary topic of
Injective function
Label
enInjective function
Link from a Wikipage to an external page
jeff560.tripod.com/i.html
www.khanacademy.org/math/linear-algebra/v/surjective--onto--and-injective--one-to-one--functions
Link from a Wikipage to another Wikipage
Algebraic structure
Axiom of choice
Bijective function
Cantor–Bernstein–Schroeder theorem
Cardinal number
Cartesian plane
Category:Basic concepts in set theory
Category:Functions and mappings
Category:Types of functions
Category of sets
Category theory
Codomain
Constructive mathematics
Contraposition
Distinct (mathematics)
Domain of a function
Element (mathematics)
Embedding
Empty function
Empty set
Exponential function
File:Injection.svg
File:Injective composition2.svg
Finite set
Function (mathematics)
Homomorphism
Horizontal line test
Identity function
Image (function)
Image (mathematics)
Inclusion function
Inclusion map
Indecomposability (constructive mathematics)
Inverse function
John Wiley & Sons
Map (mathematics)
Mathematical intuition
Mathematics
Monomorphism
Naive Set Theory (book)
Natural logarithm
Partial bijection
Partial function
Range of a function
Real line
Retract (category theory)
Singleton set
Subset
Up to isomorphism
Vector space
SameAs
Birebir fonksiyon
Disĵeto
Eintæk vörpun
Fonzion iniettiva
Função injectiva
Funció injectiva
Función inyectiva
Funciono injektiva
Funcție injectivă
Functio iniectiva
Fungsi injektif
Funkcja różnowartościowa
Funtzio injektibo
Funzione iniettiva
Injeccion (matematicas)
Injectie (wiskunde)
Injection (mathematica)
Injection (mathématiques)
Injective function
Injective function
Injekcija (matematika)
Injeksjon i matematikk
Injektiivne funktsioon
Injektio
Injektiv
Injektive Funktion
Injektiv funksjon
Injektiv funktion
Injektív leképezés
Injektivna funkcija
Injektivna funkcija
Injektivna preslikava
m.0c95n
m4vy
Prosté zobrazení
Prosté zobrazenie
Q182003
Đơn ánh
Ένα προς ένα
Ін'єкція (математика)
Ін’екцыя (матэматыка)
Инекция
Инъективті функция
Инъекция (математика)
Инјективна функција
Инјективно пресликавање
פונקציה חד-חד-ערכית
تابع یک‌به‌یک
دالة متباينة
فانکشنی یەکبەیەک
एकैकी फलन
உள்ளிடுகோப்பு
ฟังก์ชันหนึ่งต่อหนึ่ง
单射
単射
단사 함수
SeeAlso
List of set identities
Relations
Sets
Subject
Category:Basic concepts in set theory
Category:Functions and mappings
Category:Types of functions
Thumbnail
Injection.svg?width=300
WasDerivedFrom
Injective function?oldid=1122880558&ns=0
WikiPageLength
15716
Wikipage page ID
45196
Wikipage revision ID
1122880558
WikiPageUsesTemplate
Template:=
Template:≠
Template:Annotated link
Template:Authority control
Template:Citation
Template:Commons category
Template:Em
Template:Functions
Template:Further
Template:Gallery
Template:Hatnote
Template:Math
Template:Mathematical logic
Template:Redirect
Template:Reflist
Template:Refn
Template:See also
Template:Short description
Template:Slink
Template:Wiktionary