Question

Perguntas sobre Fatorial​

Answer 1

Resposta:

Respostas abaixo:

Explicação passo-a-passo:

1)

a) 7!/4!=7.6.5.4!/4!=7.6.5=210

b) (3!5!)/(4!6!)=(3!5!)/(4.3!6.5!)=1/(4.6)=1/24

c) 12!/(10!+9!)=12.11.10.9!/(10.9!+9!)=12.11.10/(10+1)=12.11.10/11=12.10=120

d) (12!-13!)/12!=(12!-13.12!)/12!=1-13=-12

2)

a) n!/(n-2)!=n.(n-1).(n-2)!/(n-2)!=n.(n-1)=n²-n

b) (n+1)!/(n+2)!=(n+1)!/(n+2).(n+1)!=1/(n+2)

c) [(n+3)!(n-1)!]/[(n-2)!(n+2)!]=

[(n+3).(n+2)!(n-1).(n-2)!]/[(n-2)!(n+2)!]=(n+3).(n-1)=n²+2n-3