Functions:Forward Image

In mathematics, the image of a function is the set of all output values it may produce.

More generally, evaluating a given function $f$ at each element of a given subset {\displaystyle A}A of its domain produces a set, called the "image of {\displaystyle A}A under (or through) {\displaystyle f}f". Similarly, the inverse image (or preimage) of a given subset {\displaystyle B}B of the codomain of {\displaystyle f,}f, is the set of all elements of the domain that map to the members of {\displaystyle B.}B.

Image and inverse image may also be defined for general binary relations, not just functions.