Question

Let $A=\{1,2\}$ and $B=\{3,4\}$. Find the number of relations from $A$ to $B$.

Answer 1

$A=\{1,2\}$

$B=\{3,4\}$

Relation from $A$ to $B=\{(1,3),(1,4),(2,3),(2,4)\}$.