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Author Topic:   0.99999~ = 1 ?
New Cat's Eye
Inactive Member


Message 151 of 237 (544348)
01-25-2010 3:04 PM


You won a math debate...
read aloud for the lulz

Replies to this message:
 Message 152 by cavediver, posted 01-25-2010 3:12 PM New Cat's Eye has replied

  
cavediver
Member (Idle past 3664 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 152 of 237 (544350)
01-25-2010 3:12 PM
Reply to: Message 151 by New Cat's Eye
01-25-2010 3:04 PM


You won a math debate...
Huh? Sorry, you lost me.
But it does remind me of when we had a crowd of 5000, all politely arguing separate points of view. Ah, the joys of mass debating...
Now, what were you talking about?

This message is a reply to:
 Message 151 by New Cat's Eye, posted 01-25-2010 3:04 PM New Cat's Eye has replied

Replies to this message:
 Message 153 by New Cat's Eye, posted 01-25-2010 3:16 PM cavediver has replied

  
New Cat's Eye
Inactive Member


Message 153 of 237 (544351)
01-25-2010 3:16 PM
Reply to: Message 152 by cavediver
01-25-2010 3:12 PM


it sounds like 'you wanna masturbate'
did you not read it out loud?
Edited by Catholic Scientist, : No reason given.

This message is a reply to:
 Message 152 by cavediver, posted 01-25-2010 3:12 PM cavediver has replied

Replies to this message:
 Message 154 by cavediver, posted 01-25-2010 3:24 PM New Cat's Eye has replied

  
cavediver
Member (Idle past 3664 days)
Posts: 4129
From: UK
Joined: 06-16-2005


Message 154 of 237 (544353)
01-25-2010 3:24 PM
Reply to: Message 153 by New Cat's Eye
01-25-2010 3:16 PM


did you not read it out loud?
Yes, but you obviously didn't read my reply

This message is a reply to:
 Message 153 by New Cat's Eye, posted 01-25-2010 3:16 PM New Cat's Eye has replied

Replies to this message:
 Message 155 by New Cat's Eye, posted 01-25-2010 3:35 PM cavediver has not replied

  
New Cat's Eye
Inactive Member


Message 155 of 237 (544356)
01-25-2010 3:35 PM
Reply to: Message 154 by cavediver
01-25-2010 3:24 PM


ahhh, mass debating.
heh, yeah, I missed that >.<

This message is a reply to:
 Message 154 by cavediver, posted 01-25-2010 3:24 PM cavediver has not replied

Replies to this message:
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lyx2no
Member (Idle past 4737 days)
Posts: 1277
From: A vast, undifferentiated plane.
Joined: 02-28-2008


Message 156 of 237 (544363)
01-25-2010 4:37 PM
Reply to: Message 155 by New Cat's Eye
01-25-2010 3:35 PM


Ok you two
Mass debating belongs in a religion thread.

You are now a million miles away from where you were in space-time when you started reading this sentence.

This message is a reply to:
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RAZD
Member (Idle past 1425 days)
Posts: 20714
From: the other end of the sidewalk
Joined: 03-14-2004


Message 157 of 237 (544379)
01-25-2010 6:29 PM
Reply to: Message 145 by cavediver
01-25-2010 10:45 AM


Re: ~ to the 10th power?
Hi cavediver, it may just be a mathematical semantic thing.
Yes, and neither are assumed to be one. However, they are reasoned to be the same as each other, by virtue of the continued long division. In the same way that you reason that your .999~ multiplied by 2 and with 1 subtracted is also the same, depsite the fact that it would not be true for a terminating decimal .9999.....9
This also holds for all the frame shift proofs as well.
I'm aware that functionally they are similar, I just find them conceptually different, as one seems (unnecessarily) more manipulated than the other, and it seems that the main argument is about how you phrase the problem, rather than the actual solutions.
My dad makes a comment about mathematicians understanding the problems very well, but not understanding how to communicate their understanding to those who do not understand maths, so I try for the simplest paths possible.
It's quite interesting to see the variety of ways people have gone about this, and I'm rather astounded that this thread has persisted so long.
It might be interesting to see how people think which explanations are the ones that best convince them -- Huntard and Straggler and any other lurkers who had trouble with this issue.
enjoy.

we are limited in our ability to understand
by our ability to understand
Rebel American Zen Deist
... to learn ... to think ... to live ... to laugh ...
to share.


• • • Join the effort to solve medical problems, AIDS/HIV, Cancer and more with Team EvC! (click) • • •

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Replies to this message:
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 Message 163 by Son Goku, posted 01-26-2010 5:17 AM RAZD has seen this message but not replied
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Dr Adequate
Member (Idle past 305 days)
Posts: 16113
Joined: 07-20-2006


Message 158 of 237 (544383)
01-25-2010 7:04 PM
Reply to: Message 143 by RAZD
01-25-2010 7:33 AM


Re: ~
The proof was intended to show that 1 ≡ 0.999~ by assuming that it wasn't, and then showing that this results in a contradiction.
Mmm ... not really.
In the process it uses another version of 0.999~ and the problem is that if one is not 1 then the other isn't either and it remains half way between. One can't use the conclusion as part of the proof eh?
But that's not what's happening.
Look, call 0.9999~ x.
Then we have (1+x)/2 = x.
So 1 + x = 2x
i.e. 1 + x = x + x.
So 1 = x.

This message is a reply to:
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Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 159 of 237 (544391)
01-25-2010 9:44 PM
Reply to: Message 143 by RAZD
01-25-2010 7:33 AM


RAZD writes:
quote:
In the process it uses another version of 0.999~
Incorrect.
In the process, it calculates that (1 + 0.999...)/2 = 0.999.... This can only be true if 0.999... = 1.
Are you saying that (1 + 0.999...)/2 does not result in a pair-wise identity in each decimal place with 0.999...?
Let us not play dumb.
quote:
One can't use the conclusion as part of the proof eh?
And if that were the case, you might have a point. But instead, we are finding that a calculated value (the quotient) is identical to the constant we used. And because of that, in the context of the proof, this means that 0.999... = 1.
(x + x)/2 = x
That second "x" is a calculated x, yes, but that's the point of the proof. Because if (y + x)/2 = x, then y = x.
So we start with y = 1 and x = 0.999... and then do a calculation on it. If we wind up with 0.999..., then we know that y = x and 1 = 0.999....
Are you denying that (1 + 0.999...)/2 = 0.999...?
quote:
A much simpler process is take 0.999~, multiply it by two (=1.999~), where the 9's are exactly aligned from the decimal, and subtract the original ( 1), QED
It isn't "simpler."
It's backwards.
Your method also works since identities are isomorphic and thus the implications go both ways [(A=>B) => (B=>A)], but it is hardly simple for it requires the exact same process: Performing a mathematical operation upon an infinite decimal.
You have the exact same problem you are complaining about: What makes you think the 9s in 1.999... are the same as the 9s in 0.999...?
Easy: The mathematical operation is correct and the notation shows it to be so.
Whether we add and then divide or we multiply and then subtract is immaterial.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 143 by RAZD, posted 01-25-2010 7:33 AM RAZD has seen this message but not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 160 of 237 (544404)
01-26-2010 1:38 AM
Reply to: Message 147 by Jazzns
01-25-2010 11:49 AM


Jazzns writes:
quote:
Yea transcendentals are contained in the irrationals.
Yeah. The Rationals are simply defined as the set of numbers that can be expressed as a/b where a and b are Integers. The Irrationals are those numbers that cannot be expressed that way.
Thus pi, e, and the square root of 2 are all irrational.
Transcendental numbers are those that aren't algebraic, meaning roots of a polynomial equation with rational coefficients. The square root of 2 is algebraic, but pi and e aren't.
And there is the constructible dichotomy: Those numbers which can be constructed via straightedge and compass are "constructible" while those that can't aren't. The square root of 2 is constructible, pi is not. And that's why it is impossible to square the circle: The square root of pi is not constructible.
All constructible numbers are algebraic, but not all algebraic numbers are constructible. All rational numbers are constructible, but not all constructible numbers are rational.
There are all sorts of ways to divide the real numbers down. That's part of the reason that Real Analysis is so fascinating: There are just so many numbers and with different properties to them that you can divvy them up any which way and learn all sorts of interesting things about the way numbers can behave.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 147 by Jazzns, posted 01-25-2010 11:49 AM Jazzns has not replied

  
Rrhain
Member
Posts: 6351
From: San Diego, CA, USA
Joined: 05-03-2003


Message 161 of 237 (544405)
01-26-2010 2:13 AM
Reply to: Message 157 by RAZD
01-25-2010 6:29 PM


RAZD writes:
quote:
I'm aware that functionally they are similar
It is more than just "similar." They are identical. This is part of the reason why in the proof that the Reals are uncountable that you have to choose the notation of the repeated decimal format.
quote:
I just find them conceptually different, as one seems (unnecessarily) more manipulated than the other, and it seems that the main argument is about how you phrase the problem, rather than the actual solutions.
And yet, as I have pointed out more than once, there is at least one problem that hinges upon this equivalency.
There are plenty of things in physics that make absolutely no sense intuitively and yet we know they are true. We run the experiments and we get results that only make sense if the world works in ways completely against what we would normally expect. The very idea that no, you can't go faster than the speed of light is one of them. A car going at 40 miles an hour crashes headlong into a car coming toward it at 50 miles an hour. Their combined force impact is NOT equivalent to the single mass of both cars crashing into a stationary object at 90 miles an hour. Relativistic effects are present at all levels. The only reason we didn't figure it out sooner is because the effect is so small that we didn't notice it. Now that we can mover faster and farther, those effects become more noticeable.
Mathematics is the same way: Some things don't seem right but they are and unlike physics, you can actually prove it forever to be true.
quote:
My dad makes a comment about mathematicians understanding the problems very well, but not understanding how to communicate their understanding to those who do not understand maths, so I try for the simplest paths possible.
The thing is that just like physics and biology, the really interesting questions don't have simple answers. There's a reason that it takes over 60,000 steps to prove that 1 + 1 = 2 from first principles. It took Russell and Whitehead years to develop the proof and Russell nearly went mad over it. There are plenty of pithy phrases we can say, but to be rigorous about it requires that we abandon pretenses of simplicity and admit that it's hard work to understand this stuff.

Rrhain

Thank you for your submission to Science. Your paper was reviewed by a jury of seventh graders so that they could look for balance and to allow them to make up their own minds. We are sorry to say that they found your paper "bogus," specifically describing the section on the laboratory work "boring." We regret that we will be unable to publish your work at this time.

Minds are like parachutes. Just because you've lost yours doesn't mean you can use mine.

This message is a reply to:
 Message 157 by RAZD, posted 01-25-2010 6:29 PM RAZD has seen this message but not replied

Replies to this message:
 Message 162 by Huntard, posted 01-26-2010 4:01 AM Rrhain has replied
 Message 168 by AnswersInGenitals, posted 01-26-2010 12:26 PM Rrhain has not replied

  
Huntard
Member (Idle past 2315 days)
Posts: 2870
From: Limburg, The Netherlands
Joined: 09-02-2008


Message 162 of 237 (544410)
01-26-2010 4:01 AM
Reply to: Message 161 by Rrhain
01-26-2010 2:13 AM


Rrhain writes:
It took Russell and Whitehead years to develop the proof and Russell nearly went mad over it.
What is it about math that makes people go mad, anyway? Or is it simply mad people that practice math?

I hunt for the truth
I am the one Orgasmatron, the outstretched grasping hand
My image is of agony, my servants rape the land
Obsequious and arrogant, clandestine and vain
Two thousand years of misery, of torture in my name
Hypocrisy made paramount, paranoia the law
My name is called religion, sadistic, sacred whore.
-Lyrics by Lemmy Kilmister of Motorhead

This message is a reply to:
 Message 161 by Rrhain, posted 01-26-2010 2:13 AM Rrhain has replied

Replies to this message:
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Son Goku
Inactive Member


Message 163 of 237 (544412)
01-26-2010 5:17 AM
Reply to: Message 157 by RAZD
01-25-2010 6:29 PM


Re: ~ to the 10th power?
Hey RAZD,
Is my proof incorrect or to you just think it's unnecessarily complicated? If it is the latter, what in particular do you find unnecessary. It's always good to know where explanations can be improved.

This message is a reply to:
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Dr Adequate
Member (Idle past 305 days)
Posts: 16113
Joined: 07-20-2006


Message 164 of 237 (544417)
01-26-2010 6:24 AM
Reply to: Message 162 by Huntard
01-26-2010 4:01 AM


What is it about math that makes people go mad, anyway? Or is it simply mad people that practice math?
Well, seriously, I don't think it's particularly an occupational hazard any more than for painters or poets or what-have-you.
But even then, I don't think that it's particularly a hazard for creative people. Psychologists used to call schizophrenia "truck-drivers' disease". Madness doesn't particularly strike down the highly creative, it's more that highly creative people are far more likely to have someone write their biographies. You are far more likely to find out that your favorite physicist has spent time in a mental hospital than you are to find out that the clerk at your local grocery store has done so, because no-one is prying into the life of the latter.
I remember when I stopped reading biographies of famous men. It was when I read a biographer of C. S. Lewis write that there was "no evidence" that his marriage was ever consummated.
What did he want, a bloody sheet?
Um ... I've gone far enough off topic, I'll shut up now.

This message is a reply to:
 Message 162 by Huntard, posted 01-26-2010 4:01 AM Huntard has not replied

Replies to this message:
 Message 166 by onifre, posted 01-26-2010 8:54 AM Dr Adequate has replied

  
Straggler
Member
Posts: 10333
From: London England
Joined: 09-30-2006


Message 165 of 237 (544421)
01-26-2010 8:17 AM
Reply to: Message 157 by RAZD
01-25-2010 6:29 PM


Re: ~ to the 10th power?
It might be interesting to see how people think which explanations are the ones that best convince them -- Huntard and Straggler and any other lurkers who had trouble with this issue.
Well I was convinced of the wrongness of my initial intuitive assertion pretty much straight away. Just looking at what others had written and thinking about it a bit convinced me of that on a rational level. I just didn't like it. It didn't feel right. I pursued the matter to A) Try and explain why I thought intuition and fact were so at odds B) To find a way of reconciling the two in my own head.
I think I achieved both (to my own satisfaction anyway) by thinking of this in terms of an infinite series and asymptotes. As per Message 79
Straggler thinking to himself out loud writes:
Even if we think of 0.999R as the infinitie series 9/10 + 9/100 + 9/1000 + 9/10000 + ...... as is the correct way to think of this then I think in our heads we intuitively do the conceptual equivalent of plotting y as the sum of the series and x as the number of terms in the series. In which case y never actually equals 1.
But as you say 0.999R isn't the sum of the series as such. It is the asymptotic value.
It all makes more sense to me expressed like that anyway.
All of which Mr Jack had been saying to me in so many words anyway. It was just this particular approach/phraseology that made the penny drop in my own intuitive head.

This message is a reply to:
 Message 157 by RAZD, posted 01-25-2010 6:29 PM RAZD has seen this message but not replied

  
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