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  #1 (permalink)  
Old 16-March-2005, 01:17 AM
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Normandy6644 Normandy6644 is offline
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Default Two reasons why .999...=1

I wanted to post this in one of the other threads, but I couldn't decide which and I it didn't really fit in either. I know these have both been mentioned several times now (including a few by me!), but it can't hurt to look at them again, especially if you are new to the discussion. Here they are, in all their beauty.

*Note: If it seems excessive to start yet another thread about this, by all means delete it and I can post this in one of the others.

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Old 16-March-2005, 02:03 AM
W.F. Tomba W.F. Tomba is offline
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My math is very rusty, so I'm probably making a mistake here, but shouldn't that say 9/10^n in step 5 of the second one?
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Old 16-March-2005, 02:08 AM
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Yeah, there are a couple of mistakes in the second one. The sum should be 9*(1/10^n). Otherwise, your line 7 doesn't make any sense; 1-9/10 = 1/10
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Old 16-March-2005, 02:10 AM
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Yep, fixed. Sorry, LaTeX can be screwy if you're in a hurry! ops:
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Old 16-March-2005, 02:18 AM
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Still not quite right.

You still have the 9/10 everywhere in line 7. You should have 9 \sum\limits_{n=1}^\infty \left ( \frac{1}{10} \right )^n = 9 \frac{\frac{1}{10}}{1-\frac{1}{10}}} = 1
or something

edit-heh I think you fixed it while I was typing this
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Old 16-March-2005, 02:24 AM
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The way I look at it, we have an entire forum dedicated to the lunar conspiracies. Until this math issue is resolved, I don't care how many threads it takes.
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Old 16-March-2005, 02:33 AM
W.F. Tomba W.F. Tomba is offline
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It still looks wrong to me. Look at step 7. You've got r=9/10 in the numerator and r=1/10 in the denominator.

r should be 1/10, shouldn't it? The sum is 9 times a geometric series with r=1/10.

That gives you 9*((1/10)/(1-(1/10)))

=9*((1/10)/(9/10))

=(9/10)/(9/10)

=1
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Old 16-March-2005, 02:34 AM
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Aaaaaghhh! I mentioned these threads to my wife.

Her: Well, it doesn't
Me: Yes it does
Her: No, it doesn't
Me: Yes it does
Her: No, it doesn't
Me: Yes it does
Her: No, it doesn't
Me: Yes it does
.
.
.

You get the picture.

So, now I'm really going to follow this simple solution once those kinks get worked out I'll show it to her.
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Old 16-March-2005, 02:37 AM
Severian Severian is offline
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Quote:
Originally Posted by W.F. Tomba
It still looks wrong to me. Look at step 7. You've got r=9/10 in the numerator and r=1/10 in the denominator.

r should be 1/10, shouldn't it? The sum is 9 times a geometric series with r=1/10.

That gives you 9*((1/10)/(1-(1/10)))

=9*((1/10)/(9/10))

=(9/10)/(9/10)

=1
His line 7 has 9/10 in the numerator...
Yours has 9*(1/10)
He just multiplied the 9 in
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Old 16-March-2005, 02:39 AM
W.F. Tomba W.F. Tomba is offline
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OK, but in line 6 he still says that r=9/10. I guess that was confusing me.
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Old 16-March-2005, 02:40 AM
Severian Severian is offline
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Oh yeah, he sure does. He doesn't mean it
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Old 16-March-2005, 02:41 AM
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Quote:
Originally Posted by Captain Kidd
Her: Well, it doesn't
Me: Yes it does
Her: No, it doesn't
Me: Yes it does
Her: No, it doesn't
Me: Yes it does
Her: No, it doesn't
Me: Yes it does

I think you've just summed up the previous 3 threads on this subject! By the way, I haven't the math to follow the second method, but the first has completely clinched it for me. That's something I can show someone who doesn't agree....
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Old 16-March-2005, 02:42 AM
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Quote:
Originally Posted by Severian
Oh yeah, he sure does. He doesn't mean it
Argh!! I will fix this thing eventually!
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Old 16-March-2005, 02:43 AM
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Quote:
Originally Posted by SciFi Chick
The way I look at it, we have an entire forum dedicated to the lunar conspiracies. Until this math issue is resolved, I don't care how many threads it takes.
We should add this to the file of "Who killed kennedy" and "How were the pyramids built". We're just never going to be able to solve it.
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Old 16-March-2005, 02:45 AM
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Quote:
Originally Posted by Inferno
Quote:
Originally Posted by SciFi Chick
The way I look at it, we have an entire forum dedicated to the lunar conspiracies. Until this math issue is resolved, I don't care how many threads it takes.
We should add this to the file of "Who killed kennedy" and "How were the pyramids built". We're just never going to be able to solve it.
I'm not sure I agree about the "who killed Kennedy", but I'm with you 100% on the "how were the pyramids built"
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Old 16-March-2005, 02:48 AM
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9*(1/10) is the same as 9/10..
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Old 16-March-2005, 02:49 AM
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There, it should be okay now.

Note to self: Before posting something, make sure to doublecheck it! #-o
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Old 16-March-2005, 02:49 AM
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Quote:
Originally Posted by Inferno
"How were the pyramids built"
http://www.badastronomy.com/phpBB/vi...=435932#435932
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Old 16-March-2005, 02:51 AM
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Quote:
Originally Posted by Normandy6644
There, it should be okay now.

Note to self: Before posting something, make sure to doublecheck it! #-o
8-[ er..you still say r=9/10 between lines 5 and 6
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Old 16-March-2005, 02:56 AM
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I suppose rule 6 is proven somewhere else, or is that common sense?
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Old 16-March-2005, 02:56 AM
W.F. Tomba W.F. Tomba is offline
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Quote:
Originally Posted by Severian
Quote:
Originally Posted by Normandy6644
There, it should be okay now.

Note to self: Before posting something, make sure to doublecheck it! #-o
8-[ er..you still say r=9/10 between lines 5 and 6
Actually, he's fixed it; I see r=1/10 there. You might have to re-reload the page or something.
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Old 16-March-2005, 02:57 AM
Severian Severian is offline
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ah, my bad ops:
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