+0  
 
0
99
2
avatar

simplify n!/2!(n-2)!

then convert it to the form of n2 + bn + c = 0

 

Been stuck on this question for days!!!!

 

The full question is:

 

One model of boat has n optional features available. When 2 optional features are chosen for this model of boat, 45 packages are available. The number of optional features, n, available for this model of boat can be determined using the following expression:          n! / 2!(n - 2)! = 45        n > 2

                                                                                                                                                                                  

Simplify this expression, and write the answer in the form n2 + bn + c = 0. Please show all work.

 May 19, 2020
edited by Guest  May 19, 2020
edited by Guest  May 19, 2020
edited by Guest  May 19, 2020
 #1
avatar+111455 
+1

    n!                         (n) ( n - 1)

_________   =       __________  =   (1/2) ( n )  ( n - 1)   =  (1/2) (n^2 - n)

(n - 2)! 2!                      2

 

 

So.....I guess you  want to set this  to  0 ???

 

(1/2) ( n^2  -  n)  =   0        multiply  both sides  by 2

 

n^2 - n    =   0

 

cool cool cool

 May 19, 2020
 #2
avatar
0

The full question is as followed:

 

One model of boat has n optional features available. When 2 optional features are chosen for this model of boat, 45 packages are available. The number of optional features, n, available for this model can be determined using the following expression:               n!

                                                                                                                                                                           ------------------  = 45           n > 2

                                                                                                                                                                             2! (n - 2)!               

                 Simplify this expression, and writhe your answer in the form    n2 + bn + c = 0. Show all work.                                                                                                                                                            

Guest May 19, 2020

5 Online Users