Question

COMO RESOLVER '' (n+2)! - (n+1)!/ n(n-1)!

Answer 1

$\frac{(n+2)!-(n+1)!}{n*(n+1)!} = \frac{(n+2)*(n+1)!-(n+1)!}{n*(n+1)!} = \frac{(n+1)![(n+2)-1]}{n*(n+1)!} = \\ \\ \to \boxed{\frac{n+1}{n}}$

Espero ter ajudado. :))