simply the expressions

Question

2!(n-3)!/N-1)!

 

I get as far as 2x1(n-3)(n-2)(n-1)/(n-1)

Answer 1

Hmmm. Firstly, assuming N is a typo and all n's are lower case. 

 

 I am thinking it is more like this. 

 

2(n-3)(n-4)(n-5)! ⁄ (n-1)(n-2)(n-3)(n-4)(n-5)!   You see the pattern.

 

Cancel starting at (n-3) in numerator and denominator.

 

That leaves 2 OVER (n-1)(n-2)  or

 

2 ⁄ (n-1)(n-2)

 

 

Answer 2

... or 2(n-3)(n-2)