Category:Preimages

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This category contains results about Preimage in the context of Set Theory.
Definitions specific to this category can be found in Definitions/Preimages.


Let $Y \subseteq T$.

The preimage of $Y$ under $f$ is defined as:

$f^{-1} \sqbrk Y := \set {s \in S: \exists t \in Y: \map f s = t}$


That is, the preimage of $Y$ under $f$ is the image of $Y$ under $f^{-1}$, where $f^{-1}$ can be considered as a relation.


If no element of $Y$ has a preimage, then $f^{-1} \sqbrk Y = \O$.

Also see

Subcategories

This category has the following 3 subcategories, out of 3 total.