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Need help in this Factorial question

The question states this:

If (n+1)!+n2(n1)!=(an+1)n! (n+1)! + n^2(n-1)! = (an+1)n! find the value of a

I got upto a point where i simplified the expression to:

(n1)!(2n2+n) (n-1)! (2n^2 + n)
Reply 1
bump
is it possible to factorise your expression further?
Reply 3
Original post by ralph9694
is it possible to factorise your expression further?


I dont know. Would (n-1)! be the same after being taken out as a common factor, or would it be just be (n-1).
I meant a common factor in the second bracket.
Reply 5
Original post by brownguytorule
The question states this:

If (n+1)!+n2(n1)!=(an+1)n! (n+1)! + n^2(n-1)! = (an+1)n! find the value of a

I got upto a point where i simplified the expression to:

(n1)!(2n2+n) (n-1)! (2n^2 + n)


Try expanding the second bracket, thinking carefully about how you write a factorial in long form, namely:

n!=n(n1)(n2)...n! = n \cdot (n-1) \cdot (n-2)...

... and

(n1)!=(n1)(n2)(n3)...(n-1)! = (n-1) \cdot (n-2) \cdot (n-3)...

So what do you get when you multiply the factorial of n1n-1 by nn, and then 2n22n^2?

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