About Lesson
What is relation?
A relation from a non-empty set A to itself is a subset of cartesian product $$\mathrm{A} \times \mathrm{A}$$.
Relation from a set A to set B is a subset of cartesian product
$$
A \times B
$$
What is relation?
A relation from a non-empty set A to itself is a subset of cartesian product $$\mathrm{A} \times \mathrm{A}$$.
Relation from a set A to set B is a subset of cartesian product
$$
A \times B
$$