Question

Please select the best answer from the choices provided

A
B
C
D

Answer 1

ANSWER

C.

`(1)/(a(a - 1))`

Step-by-step explanation

We want to simplify,


`((a - 2)!)/(a!)`

Recall that,


`n!=n* (n-1)* (n-2)...2*1`

We expand only the denominator until an equivalent expression for numerator shows up.

This implies that, the above expression is


`=((a - 2)!)/(a(a - 1)(a - 2)!)`

We cancel out the common factors to get.


`=(1)/(a(a - 1))`

Therefore the correct answer is option C.