Question

If A = {1, 2, 3} and B = {a, b}, write the total number of functions from A to B.

Answer 1

Formula:
If set A has m elements and set B has n elements, then the number of functions from A to B is $n^m$.
Given:
A = {1, 2, 3} and B = {a, b}
$\Rightarrow n\left(A\right)$ = 3 and $n\left(B\right)$ = 2
$\therefore$ Number of functions from A to B = 2³ = 8