Relation Composition

Tags

math

For a relation \( R \subseteq A \times B \) and \( S \subseteq B \times C \) we define the [see page 11, composition] of \( S \) and \( R \) as \( S \circ R \subseteq A \times C \) where \( S \circ R = \{ (a, c) : \exists b \in B ((a, b) \in R \land (b, c) \in S) \} \).