Definition:Dual Relation/Complement of Inverse

Definition
Let $\RR \subseteq S \times T$ be a binary relation.

Then the dual of $\RR$ is denoted $\RR^d$ and is defined as:


 * $\RR^d := \overline {\paren {\RR^{-1} } }$

where:
 * $\RR^{-1}$ denotes the inverse of $\RR$
 * $\overline {\paren {\RR^{-1} } }$ denotes the complement of the inverse of $\RR$.