preimage

preimage
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.

See Also: image

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  • preimage — n. * * * …   Universalium

  • preimage — n …   Useful english dictionary

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  • Image (mathematics) — In mathematics, the image of a preimage under a given function is the set of all possible function outputs when taking each element of the preimage, successively, as the function s argument. DefinitionIf f : X → Y is a function from set X to set… …   Wikipedia

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