Respostas

2013-10-28T11:55:06-02:00
A) (n+2)! / (n+1)!(n+2).(n+1)! / (n+1)! = n+2
b) (n + 1)! + n! / n!(n+1).n! + n! / n! = 
n! (n+1+1)/n! = 
n+2

c) (n - 4)! / (n - 3)!
(n-4).(n-3)! / (n-3)! =
n-4

d) n! + 4! / n!