Question

Simplifique as expressões:
A) (n+2)!/(n-1)!
B) n(n+1)!/(n+2)!

Answer 1

$a) \frac{(n+2)!}{(n-1)!} = \frac{(n+2)(n+1)n(n-1)!}{(n-1)!} = (n+2)(n+1).n=(n+2)(n^{2}+n) \\ n^{3}+2n^{2}+n^{2}+2n=n^{3}+3n^{2}+2n \\ \\ b) \frac{n.(n+1)!}{(n+2)!} = \frac{n.(n+1)!}{(n+2)(n+1)!} = \frac{n}{(n+2)}$

Espero ter ajudado.

Answer 2

Oi Emilly

a) 

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

b)

n*(n+1)!/(n+2)! = n*(n+1)!(n+2)*(n+1)! = n/(n+2) 

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