Question

(к+1)!/(к-2)! помогите пожалуйста

Answer 1

(k+1)!/(k-2)!=(k+1)k(k-1)(k-2)!/(k-2)!=k(k+1)(k-1)=k^3-k.

Answer 2

(k+1)!/(k-2)!=(k-2)!(k-1)k(k+1)/(k-2)! = k(k-1)(k+1)