Question

A expressão 10! - 9!/9! equivale a:
a) 10!
b) 9!
c) 10
d) 9
e) 8

Answer 1

$\frac{10!-9!}{9!}=\\\\\frac{10\cdot9!-9!}{9!}=\\\\\frac{9!(10-1)}{9!}=\\\\\frac{10-1}{1}=\\\\\boxed{9}$