Question

simplifique as expressões a)(n-4)!/(n-3)! b)(2n)!/(2n-2)! c)(n+2)!/N!

Answer 1

Olá, tudo bem?

a)

$\dfrac{(n-4)!}{(n-3)!}=\dfrac{(n-4)!}{(n-3)\cdot(n-4)!}=\dfrac{1}{n-3};\,\,n\neq 3$

b)

$\dfrac{(2n)!}{(2n-2)!}=\dfrac{(2n)\cdot(2n-1)\cdot(2n-2)!}{(2n-2)!}=2n\cdot(2n-1);\,\,n\neq 2$

c)

$\dfrac{(n+2)!}{n!}=\dfrac{(n+2)\cdot(n+1)\cdot(n)!}{n!}=(n+2)\cdot(n+1);\,\,n\neq 0$

É isso!! :)