Question

Me ajudem ai galera [FATORIAL]

Answer 1

$\boxed{\frac{5!*8!}{4!*7!}~\to~ \frac{5*\not{4!}*8*\not7!}{\not4!*\not7!}~\to~5*8=40 }$

$\boxed{\frac{n!}{(n-1)!}~\to~ \frac{n*(n-1)!}{(n-1)!}=n }$

$\boxed{ \frac{n!}{(n+2)!}~\to~ \frac{n!}{(n+2)*(n+1)*n!}~=~ \frac{1}{(n+2)(n+1)} }$