Question

(n-1)! + (n-3)! / (n-4)! =​

Answer 1

( (n-1) (n-2) (n-3) (n-4)! + (n-3) (n-4)! ) / (n-4)!

(n-3) (n-4)! ( (n-1) (n-2) + 1) / (n-4) !

(n-3) ( (n-1) (n-2) + 1)

(n-3) (n^2 -3n + 2 + 1)

n^3 -6n^2 -6n + 9