If R is a relation from a non – empty set A to a non – emp...
-empty set A to a non-empty set B, then R is a subset of A x B, where A x B is the Cartesian product of A and B.
The Cartesian product A x B is defined as the set of all ordered pairs (a, b), where a is an element of A and b is an element of B. In other words, A x B = {(a, b) | a ∈ A and b ∈ B}.
A relation R from A to B is a subset of A x B, meaning that every element of R is an ordered pair (a, b) where a ∈ A and b ∈ B. Intuitively, a relation is a set of pairs of objects, where the first object in each pair comes from A and the second object comes from B.
For example, if A = {1, 2, 3} and B = {a, b, c}, then A x B = {(1, a), (1, b), (1, c), (2, a), (2, b), (2, c), (3, a), (3, b), (3, c)}. If R is the relation {(1, b), (2, a), (3, c)}, then R is a subset of A x B.
Note that not every subset of A x B is a relation from A to B. A relation must satisfy certain properties, depending on the context in which it is defined. For example, a function is a special kind of relation that has the property that each element in A is associated with exactly one element in B.