Cartesian Product
Let \(A\) and \(B\) be sets . We define the cartesian product of \(A\) and \(B\) to be the set \(A \times B\) of all ordered pairs of elements from \(A\) and elements of \(B\). That is:
\[ A \times B = \{(a,b) : a \in A \text{ and } b \in B\} \]