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**debjit625****Member**- Registered: 2012-07-23
- Posts: 91

Find the sum of the following geometric series

I got an answer of

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

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The essence of mathematics lies in its freedom - Georg Cantor

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,302

Hi;

What happened to the n?

**In mathematics, you don't understand things. You just get used to them.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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**debjit625****Member**- Registered: 2012-07-23
- Posts: 91

Ok I just got it

,my badSolved the problem

Debjit Roy

___________________________________________________

The essence of mathematics lies in its freedom - Georg Cantor

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**debjit625****Member**- Registered: 2012-07-23
- Posts: 91

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

Here is the answer

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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 86,302

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.Of course that result can be rigorously obtained, but who cares?Combinatorics is Algebra and Algebra is Combinatorics.**

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