Image is Subset of Codomain/Corollary 1

From ProofWiki
Jump to navigation Jump to search

Corollary to Image is Subset of Codomain

Let $\RR = S \times T$ be a relation.


The image of $\RR$ is a subset of the codomain of $\RR$:

$\Img \RR \subseteq T$


Proof

\(\ds \Img \RR\) \(=\) \(\ds \RR \sqbrk {\Dom \RR}\) Definition of Image of Relation
\(\ds \Dom \RR\) \(\subseteq\) \(\ds \Dom \RR\) Set is Subset of Itself
\(\ds \leadsto \ \ \) \(\ds \Img \RR\) \(\subseteq\) \(\ds T\) Image is Subset of Codomain

$\blacksquare$