# Bewezen functie is injectief Functie inverteren 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(x 1) = f(x 2) implies x 1 = x 2. (Equivalently, x 1 ≠ x 2 implies f(x 1) ≠ f(x 2) in the equivalent contrapositive statement.).
Domein inverse functie function: f:X->Y "every x in X maps to only one y in Y." one to one function: "for every y in Y that the function maps to, only one x maps to it". (injective - there are as many points f(x) as there are x's in the domain). onto function: "every y in Y is f(x) for some x in X. (surjective - f "covers" Y).

## Wat zijn inverse functies

The functions in Exam- ples and are not injections but the function in Example is an injection. This illustrates the important fact that whether a function is injective not only depends on the formula that defines the output of the function but also on the domain of the function.

## Domein cyclometrische functies

Bijective means both Injective and Surjective together. Think of it as a "perfect pairing" between the sets: every one has a partner and no one is left out. So there is a perfect "one-to-one correspondence" between the members of the sets. (But don't get that confused with the term "One-to-One" used to mean injective). Wanneer is een functie even of oneven The function is bijective (one-to-one and onto, one-to-one correspondence, or invertible) if each element of the codomain is mapped to by exactly one element of the domain. That is, the function is both injective and surjective. A bijective function is also called a bijection.
Periode functie bepalen Surjective means that for every “B” there is at least one matching “A.” (maybe more than one). Informally, an injection has at most one input mapped to each output, a surjection has the complete possible range in the output, and a bijection has both criteria true.

## Inverse functie van een breuk

A bijective function is a function that is both injective and surjective. Every element of the codomain appears EXACTLY once, and the cardinality of the domain and codomain are equal.

Elementaire functies vraagstukken Om te beoordelen of deze functie injectief is, moeten we naar kijken naar: 1. Elke deelfunctie afzonderlijk. 2. De gecombineerde functie in zijn geheel. Ad. 1. In de tekst hebben we gezien dat de functie F(x)=x 2 in het algemeen niet injectief is op. Op het domein {x|x 0} is deze deelfunctie echter stijgend, dus wel injectief.