Respostas

2014-08-25T18:03:01-03:00
(n+2).(n+1).n!
n!+(n+1).n!

(n+2).(n+1).n!
n!.(1+(n+1))

(n+2).(n+1)
1+n+1

n²+n+2n+2
2+n

n²+3n+2
2+n

é isso?