Question

Find A x B if A={0,1,3} and B={1,2,a,b}.

Answer 1

$\begin{array}{l} A \times B = \{ (x;y)|x \in A \wedge y \in B\} = \\ = \{ (0;1),\,(0;2),(0;a),(0;b),(1;1),\,(1;2),(1;a),(1;b),(3;1),\,(3;2),(3;a),(3;b)\} \end{array}$