Definition:Inverse Relation/Class Theory

Definition
Let $V$ be a basic universe.

Let $A$ and $B$ be subclasses of $V$.

Let $\RR \subseteq A \times B$ be a relation on $A \times B$.

The inverse relation to (or of) $\RR$ is defined as the class of all ordered pairs $\tuple {b, a}$ such that $\tuple {a, b} \in \RR$:


 * $\RR^{-1} := \set {\tuple {b, a}: \tuple {a, b} \in \RR}$