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7 replies to this topic

### #1 EventHorizon

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Posted 26 March 2008 - 01:59 AM

What is the sum of this series equal to in the limit?

2/100, 4/10000, 8/10^6, 16/10^8, 32/10^10, ...

Yeah....its a simple geometric series....but it is kinda interesting when you multiply each term by 7 and see what the sum is equal to.
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### #2 unreality

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Posted 26 March 2008 - 02:16 AM

from what I can tell the nth term is

2n/102n
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### #3 storm

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Posted 26 March 2008 - 02:20 AM

I forgot the formulae of geometric series..and i am too lazy to get help from the net
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### #4 EventHorizon

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Posted 26 March 2008 - 02:39 AM

from what I can tell the nth term is

2n/102n

That's right, though it can be simplified to a simple power of a fraction.
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### #5 bonanova

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Posted 26 March 2008 - 05:29 AM

What is the sum of this series equal to in the limit?
2/100, 4/10000, 8/10^6, 16/10^8, 32/10^10, ...
Yeah....its a simple geometric series....but it is kinda interesting when you multiply each term by 7 and see what the sum is equal to.

Spoiler for Looks like

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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #6 storm

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Posted 26 March 2008 - 07:54 AM

Spoiler for result

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### #7 bonanova

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Posted 26 March 2008 - 01:49 PM

Spoiler for result

So, echo ... guess you looked the formula up after all.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

### #8 EventHorizon

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Posted 26 March 2008 - 08:12 PM

Spoiler for the part I thought was interesting

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