Question

Equação fatorial

1) Resolva:

a) 14! / 10! =
b) 9! / 5! 3! =
c) 21! / 17! =

2) Resolva as equações aplicando os fatoriais:

a) (n+2)! / (n+1)! = 5

b) (n-3)! / (n-2)! = 10

Answer 1

Resposta:

1a)14! / 10!= 14×13×12×11×10!/10!=14×13×12×11= 2,142,448

b) 9! / 5!×3!=9×8×7×6×5! / 5!×6 = 504

c) 21! / 17!= 21×20×19×18×17! / 17!= 143,640

2.a) ( n+2)! / (n+1)!=5

(n+2)×(n+1)! / (n+1)!=5

(n+2)=5

n+2=5

n=3

b)(n-3)! / (n-2)!=10

(n-3)! / (n-2)×(n-3)!=10

1/(n-2)=10

10n-20=10

10n=30

n=30/10

n=3