Math Is Fun Forum

debjit625

Member

Registered: 2012-07-23

Posts: 101

Want to be sure...

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)

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

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Want to be sure...

Hi;

What happened to the n?

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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.

debjit625

Member

Registered: 2012-07-23

Posts: 101

Re: Want to be sure...

Ok I just got it

,my bad

Solved the problem

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

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...

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)

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

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)

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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.