Question

ajudem porfavor?!!!
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Answer 1

Olá, tudo bem?

a) n!/(n-1)!

= n×(n-1)!/(n-1)!

= n

b) n!/(n+2)!

= n!/(n+2)×(n+1)×n!

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

= 1/n²+3n+2