Respostas

  • Usuário do Brainly
2013-11-19T16:32:50-02:00
(n+2)! (n-2)! = 4 (n+1)! (n-1)!
(n+2) (n+1)! (n-2)! = 4 (n+1)! (n-1)(n-2)!
n+2 = 4(n-1)
n + 2 = 4n - 4
6 = 3n
n = 2