Question

a) Let \( A=\{7,8\} \) and \( B=\{5,4,2\} \) find \( A \times B \)

Answer 1

A={7,8} and B={5,4,2}
We know that the Cartesian product of P×Q of two non-empty sets P and Q is defined as
P×Q={(p,q):p∈P,q∈Q}

∴A×B={(7,5),(7,4),(7,2),(8,5),(8,4),(8,2)}
and B×A={(5,7),(5,8),(4,7),(4,8),(2,7),(2,8)}