Question

PRECISO DE AJUDA URGENTE, FATORIAL!

Calcular: (n-3)!/(n-5)!

6! -3! -2!/5!

(n+1)!+n!/(n-2)!

Answer 1

a) (n-3)!/(n-5)! =(n-3)!/[(n-5)(n-4)(n-3)!]=1/[(n-5)(n-4)]

b) deve ser (6! -3! -2!)/5! =(720-6-2)/120 = 712/120

c)deve ser [ (n+1)!+n!]/(n-2)!

[(n+1)n(n-1)(n-2)!+n*(n-1)(n-2)!/(n-2)!

=[(n+1)n(n-1)+n*(n-1)]

=n*(n-1)* (n+1+1) =(n-1)*(n²+2n)