Definition:Even Function

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Definition

Let $X \subset \R$ be a symmetric set of real numbers:

$\forall x \in X: -x \in X$


A real function $f: X \to \R$ is an even function if and only if:

$\forall x \in X: \map f {-x} = \map f x$


Also known as

An even function is also seen referred to as a symmetric function.

However, that usage is not recommended on $\mathsf{Pr} \infty \mathsf{fWiki}$ as there are other concepts which bear that name.


Also see

  • Results about even functions can be found here.


Sources