preimage

Definition from Wiktionary, a free dictionary

Contents 1 English 1.1 Noun 1.1.1 Synonyms 1.1.2 Related terms

[edit] English

Wikipedia

[edit] Noun

preimage (plural preimages)

1. (mathematics) The set containing exactly every member of the domain of a function such that the member is mapped by the function onto an element of a given subset of the codomain of the function. Formally, of a subset B of the codomain Y under a function ƒ, the subset of the domain X defined by

   

   For example, the preimage of {4, 9} under the squaring function is the set {−3,−2,+2,+3}.

[edit] Synonyms

• inverse image

[edit] Related terms

• image