Question

1 - Calcule o arranjo de A9,3
2 - calcule o arrajo de A18,6

Answer 1

$A_{9,3} \\ \frac{9!}{(9-3)!} = \frac{9*8*7*6*5*4*3*2*1}{6!} = \frac{362880}{6*5*4*3*2*1} = \frac{362880}{720} =504$

$A_{18,6} \\ \frac{18!}{(18-6)!} = \frac{6402373705728000}{12!} = \frac{6402373705728000}{479001600} = 13366080$

Espero ter ajudado. Valeu!