Question: 2016 Fall Final - 2
Consider a set $A$ having size 7 and a set $B$ having size 9. How many one-to-one functions
$f : A \rightarrow B$ are there?
(a)
$\frac{9!}{2}$
(b)
$\frac{7!}{2}$
(c)
$\frac{9!}{3}$
(d)
$\frac{7!}{3}$