Question

Resolva a expressão fatorial ,socorroo me ajudem pfvr

Answer 1

$Considere \ que:\\\\ (n-1)!=\frac{n!}{n}\\\\ (n+1)!=(n+1).n!\\\\ \frac{(n-1)!(n+1)!}{(n)!^2}=\frac{5}{4}\\\\ \frac{\frac{n!}{n}.(n+1).n!}{(n)!^2}=\frac{5}{4}\\\\ \frac{n+1}{n}=\frac{5}{4}\\\\ 4n+4=5n\\ n=4$