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## #1 2012-12-03 20:07:27

debjit625
Member
Registered: 2012-07-23
Posts: 101

### Factorial Problem

I can't solve this one ...
Find n ,if

Thanks

Last edited by debjit625 (2012-12-03 20:08:48)

Debjit Roy
___________________________________________________
The essence of mathematics lies in its freedom - Georg Cantor

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## #2 2012-12-03 20:10:39

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Factorial Problem

Hi;

n = 49.

Solve this:

(n+2)(n+1) = 2550

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #3 2012-12-03 20:13:04

bob bundy
Registered: 2010-06-20
Posts: 8,337

### Re: Factorial Problem

hi debjit625

So you just need to solve

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #4 2012-12-03 20:19:42

debjit625
Member
Registered: 2012-07-23
Posts: 101

### Re: Factorial Problem

Ok I have seen this in my book too but ,I didn't understood how

expands into
,is their any special rules or am I missing something very basic

Debjit Roy
___________________________________________________
The essence of mathematics lies in its freedom - Georg Cantor

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## #5 2012-12-03 20:21:31

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Factorial Problem

Hi;

(n+2)! = (n+2)(n+1)n (n-1)(n-2)(n-3)...1

n! =n (n-1)(n-2)(n-3)...1

(n+2)! = (n+2)(n+1)n!

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #6 2012-12-03 20:32:41

debjit625
Member
Registered: 2012-07-23
Posts: 101

### Re: Factorial Problem

Now I got it thanks guys, it was so simple ,my book didnt have enough of factorials its more about permutation can you guys give me some resource on factorials...

Thanks

Debjit Roy
___________________________________________________
The essence of mathematics lies in its freedom - Georg Cantor

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## #7 2012-12-03 20:35:38

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Factorial Problem

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #8 2012-12-03 20:39:49

debjit625
Member
Registered: 2012-07-23
Posts: 101

### Re: Factorial Problem

Thanks again...

Debjit Roy
___________________________________________________
The essence of mathematics lies in its freedom - Georg Cantor

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## #9 2012-12-03 20:41:24

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Factorial Problem

Hi;

Please check post #7, they get more and more difficult.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #10 2012-12-04 05:54:07

debjit625
Member
Registered: 2012-07-23
Posts: 101

### Re: Factorial Problem

Thanks bobbym for the link http://www.themathpage.com/aprecalc/factorial.htm
as I was searching factorial problems involving variables and it had some great stuff.

Debjit Roy
___________________________________________________
The essence of mathematics lies in its freedom - Georg Cantor

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## #11 2012-12-04 13:16:57

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Factorial Problem

Hi debjit625;

You are welcome.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline