Question

calcule: (fotorial)
A9,2 ----------

Answer 1

$\boxed{A_{9,2} =\frac{9!}{(9-2)!}}$
$\boxed{A_{9,2} =\frac{9!}{7!}}$
$\boxed{A_{9,2} =\frac{9*8*7!}{7!}}$
$\boxed{A_{9,2} =9*8}$
$\boxed{\boxed{Resposta:A_{9,2} =72}}$