Question

Calcule as combinações c 11,3 e c9,6 e c6,3

Answer 1

Cn,p = n!/p!(n-p)

C9,6 = 9!/6!(9-6)
C9,6= 9.8.7.6/6!(3.2.1)
C9,6= 504/6=84

C6,3 = 6!/3!(6-3)
C6,3= 6.5.4.3!/3!(3.2.1)
C6,3=120/6=20

C11,3 = 11!/8!3!
c11,3= 11.10.9 / 3.2.1
C11,3= 990/6 = 165

Answer 2

C11,3 => $\frac{11!}{3!8!} =\ \textgreater \ \frac{11.10.9}{3.2.1} =\ \textgreater \ \frac{11.5.3}{1} =\ \textgreater \ 55.3 =\ \textgreater \ 165$

C9,6 => $\frac{9!}{6!3!} =\ \textgreater \ \frac{9.8.7}{3.2.1} = \frac{3.4.7}{1} =\ \textgreater \ 12.7 =\ \textgreater \ 84$

C6,3 => $\frac{6!}{3!3!} =\ \textgreater \ \frac{6.5.4}{3.2.1} =\ \textgreater \ \frac{2.5.2}{1} =\ \textgreater \ 20$

É bom ir simplificando assim você fará mais rápido.