Question

6) Simplifique as expressões abaixo:​

Answer 1

Olá,

a)

$\sf \: \frac{(n - 4)!}{(n - 3)!} = \sf \: \frac{(n - 4)!}{(n - 3)(n - 4)!} = \sf \: \frac{ \cancel{(n - 4)!}}{(n - 3) \cancel{(n - 4)!}} = \frac{1}{n - 3}$

b)

$\sf \: \frac{2n!}{(2n - 2)!} = \sf \: \frac{2n(2n - 1)(2n - 2)!}{(2n - 2)!} = \sf \: \frac{2n(2n - 1) \cancel{(2n - 2)!}}{ \cancel{(2n - 2)!} } =2n(2n - 1) = 4 {n}^{2} - 2n$