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## #1 2013-03-10 21:09:01

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

### Want to be sure...

Find the sum of the following geometric series

But the book gives an answer of

I think its a mistake ,it should be

Or am I wrong

Just want to be sure...

Thanks

Last edited by debjit625 (2013-03-10 21:26:58)

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

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## #2 2013-03-10 21:18:15

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

### Re: Want to be sure...

Hi;

What happened to the 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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## #3 2013-03-10 21:19:10

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

### Re: Want to be sure...

Ok I just got it

Solved the problem

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

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## #4 2013-03-10 21:20:48

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

### Re: Want to be sure...

Sorry I was in hurry its will be -n .I edited it on the first post too...

The problem was it just got out of my mind about multiplicative inverse i.e..

Thanks

Last edited by debjit625 (2013-03-10 21:27:53)

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

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## #5 2013-03-10 21:21:22

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

### Re: Want to be sure...

That is okay. Glad you figured it out.

That is the answer mathematica gets too.

Last edited by bobbym (2013-03-10 21:32:44)

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