Relations, Functions, and Matrices 4.1

Given a set S where it is a subset of S x S (a set of ordered pairs of elements of S).

A relation in which each 1st component and each 2nd component appears only once in the relation.

A relation in which some 1st component s₁ appears more than once; that is, one s₁ is paired with more than one second component.

A relation in which some second component s₂ is paired with more than one first component.

A relation in which at least one s₁ is paired with more than one second component and at least one s₂ is paired with more than one first component.