Category:Horizontal Section of Sets

This category contains results about Horizontal Section of Sets.

Let $X$ and $Y$ be sets.

Let $E \subseteq X \times Y$.

Let $y \in Y$.

We define the $y$-horizontal section $E^y$ of $E$ by:

$E^y = \set {x \in X : \tuple {x, y} \in E}$