Respostas

2014-03-20T00:31:42-03:00
(n+1)!=(n+1).n!
(n+2)!=(n+2).(n+1).n!

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

b)n.(n-1)!-(n-1)!/(n!/(n.(n-1)))
(n-1)!.(n-1).n.(n-1)/n.(n-1)!

(n-1).(n-1)

1 5 1