Question

Combinações simples c7 3

Answer 1

Explicação passo-a-passo:

$\sf \dbinom{n}{k}=\dfrac{n!}{k!\cdot(n-k)!}$

$\sf \dbinom{7}{3}=\dfrac{7!}{3!\cdot(7-3)!}$

$\sf \dbinom{7}{3}=\dfrac{7!}{3!\cdot4!}$

$\sf \dbinom{7}{3}=\dfrac{7\cdot6\cdot5\cdot4!}{3!\cdot4!}$

$\sf \dbinom{7}{3}=\dfrac{7\cdot6\cdot5}{3!}$

$\sf \dbinom{7}{3}=\dfrac{7\cdot6\cdot5}{6}$

$\sf \dbinom{7}{3}=7\cdot5$

$\sf \dbinom{7}{3}=35$