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FINAL PROOF: 0.9(bar) = 1!!!!!!!!!!!!!!!!!!

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Jonas Hartwig

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Feb 16, 1997, 3:00:00 AM2/16/97
to

I've seen that some of you have difficulties in understanding
the fact that 0.9(bar) infact is the same number as 1. Here
comes a proof:

we let x = 0.9(bar)
then 10x = 9.9(bar) since the 9s goes on for ever
10x-9 = 0.9(bar)
10x-9 = x (see above)
9x = 9
x = 9/9
x = 1

0.9(bar) = 1

.. and there you have it!

/Jonas Hartwig
yl...@dataphone.se

Daniel A. Markham

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Feb 18, 1997, 3:00:00 AM2/18/97
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yl...@dataphone.se (Jonas Hartwig) writes:

>I've seen that some of you have difficulties in understanding
>the fact that 0.9(bar) infact is the same number as 1. Here
>comes a proof:

>we let x = 0.9(bar)
>then 10x = 9.9(bar) since the 9s goes on for ever

Nope.
10x < 9.9(bar)

0.9(bar) ^ infinity = 0.0(bar)

1 ^ infinity = 1
therefore 0.9(bar) is not equal to 1.

--
* Dan Markham * Peanut butter on a *
* bla...@wwa.com * sand tire gets frozen *
* Game Programmer * on the rusty star of *
* Konami Computer Entertainment * a gravy pop tart. *

Stan Armstrong

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Feb 18, 1997, 3:00:00 AM2/18/97
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In article <5ebir4$t...@shoga.wwa.com>, "Daniel A. Markham"
<bla...@sashimi.wwa.com> writes
>
>Nope.
Yup!

>10x < 9.9(bar)
>
>0.9(bar) ^ infinity = 0.0(bar)
This would only be true if you presume the inequality, which is what you
are seeking to prove. You have proved nothing by this circular
argument..

>
>1 ^ infinity = 1
>therefore 0.9(bar) is not equal to 1.
>
>
>

--
Stan Armstrong

Lee Jaap

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Feb 18, 1997, 3:00:00 AM2/18/97
to

In article <5ebir4$t...@shoga.wwa.com> bla...@sashimi.wwa.com (Daniel A. Markham) writes:
|>yl...@dataphone.se (Jonas Hartwig) writes:
|>
|>>I've seen that some of you have difficulties in understanding
|>>the fact that 0.9(bar) infact is the same number as 1. Here
|>>comes a proof:
|>
|>>we let x = 0.9(bar)
|>>then 10x = 9.9(bar) since the 9s goes on for ever
|>
|>Nope.
|>10x < 9.9(bar)

Prove it.

|>0.9(bar) ^ infinity = 0.0(bar)

Prove it.

|>1 ^ infinity = 1

One out of three correct so far.

|>therefore 0.9(bar) is not equal to 1.

You can't prove something if your assumptions are wrong.
--
J Lee Jaap <Jaa...@ASMSun.LaRC.NASA.Gov> +1 757/865-7093
employed by, not necessarily speaking for,
AS&M Inc, Hampton VA 23666-1340

Brad Ballinger

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Feb 19, 1997, 3:00:00 AM2/19/97
to

Here's a fresh approach to the problem that I haven't seen yet.

What if you were to define .(9bar) recursively, thereby avoiding the entire
issue of infinity, infinite sums, etc.?

This is what I mean: Let's define a new symbol, a, which will function just
like a digit but isn't an already defined thing. For instance,

.a means a/10,
.0a means a/100,
.9a means .9 + a/100

...and so on.

In particular, we'd like it to have the property that .a = .9a, because it
would then follow that .a = .9a = .99a = .999a = ...

So let's suppose such a thing exists. Then we'd have:

.a = .9a Multiply by 100;
10 * a = 90 + a
9 * a = 90
a = 10 (1)

It can be verified that if a = 10, then in fact .a = .9a = .99a = ...
and so such a thing is well-defined.

Let b = 9.(9bar). Observe that .b = .(9bar) = .9(9bar) = .9b, and so by
the argument above, b = 10.

Equivalently, .(9bar) = 1 .

This proof does not use infinity, so there shouldn't be any objections to it
on that ground. I suppose I could have spent more time giving a really really
solid exposition, in which all the notation was carefully laid out, but that
would reduce to the same core argument. Modulo that, I believe this is a
proof, independent of any underlying notions of limiting values or whatever.

Yours,

Brad Ballinger
Out-To-Luncher Extraordinaire


Robin E. Brown

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Feb 21, 1997, 3:00:00 AM2/21/97
to Daniel A. Markham

Daniel A. Markham wrote:
>
> yl...@dataphone.se (Jonas Hartwig) writes:
>
> >I've seen that some of you have difficulties in understanding
> >the fact that 0.9(bar) infact is the same number as 1. Here
> >comes a proof:
>
> >we let x = 0.9(bar)
> >then 10x = 9.9(bar) since the 9s goes on for ever
>
> Nope.
> 10x < 9.9(bar)
>
> 0.9(bar) ^ infinity = 0.0(bar)
>
> 1 ^ infinity = 1
> therefore 0.9(bar) is not equal to 1.
>
> --
> * Dan Markham * Peanut butter on a *
> * bla...@wwa.com * sand tire gets frozen *
> * Game Programmer * on the rusty star of *
> * Konami Computer Entertainment * a gravy pop tart. *

r^infinity = 0 if and only if abs(r) < 1. Thus stating .9(bar)^infinity
= 0 assumes .9(bar) does not equal 1. You can't prove a fact by assuming
its true!

Robin

Ben J. Jacobs

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Feb 22, 1997, 3:00:00 AM2/22/97
to

Jonas Hartwig wrote:
>
> I've seen that some of you have difficulties in understanding
> the fact that 0.9(bar) infact is the same number as 1. Here
> comes a proof:
>
> we let x = 0.9(bar)
> then 10x = 9.9(bar) since the 9s goes on for ever
> 10x-9 = 0.9(bar)
> 10x-9 = x (see above)
> 9x = 9
> x = 9/9
> x = 1
>
> 0.9(bar) = 1
>
> .. and there you have it!
>
> /Jonas Hartwig
> yl...@dataphone.se

And oh my god .... we are back to square one :)

arpit...@gmail.com

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Apr 20, 2018, 6:15:04 AM4/20/18
to
Exactly...... I am on the same mission!!!

Hope if you could help me by giving some of the details you know....

Barb Knox

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Apr 26, 2018, 10:51:00 PM4/26/18
to
On 20/04/18 22:15, arpit...@gmail.com wrote:
> Exactly...... I am on the same mission!!!
>
> Hope if you could help me by giving some of the details you know....

<https://en.wikipedia.org/wiki/0.999...>


--
---------------------------
| BBB b \ Barbara at LivingHistory stop co stop uk
| B B aa rrr b |
| BBB a a r bbb | ,008015L080180,022036,029037
| B B a a r b b | ,047045,L014114L4.
| BBB aa a r bbb |
-----------------------------
Message has been deleted

b.a.ch...@gmail.com

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Sep 19, 2018, 12:04:42 PM9/19/18
to
Sooo,
1=(9/9)=[1-0.1(bar)]= 0.9999999999999999...(0.9(bar))
2=(18/9)=2(1-0.1(bar))=1.8888888888888888...(1.8(bar))
3=(27/9)=3(1-0.1(bar))=2.7777777777777777...(2.7(bar))
4=(36/9)=4(1-0.1(bar))=3.6666666666666666...(3.6(bar))
5=(45/9)=5(1-0.1(bar))=4.5555555555555555...(4.5(bar))
6=(54/9)=6(1-0.1(bar))=5.4444444444444444...(5.4(bar))
7=(63/9)=7(1-0.1(bar))=6.3333333333333333...(6.3(bar))
8=(72/9)=8(1-0.1(bar))=7.2222222222222222...(7.2(bar))
9=(81/9)=9(1-0.1(bar))=9-0.9(bar)=9-1=8.0000000000(8.0(bar))
10=(90/9)=10(1-0.1(bar))=(10-1.1(bar))=8.88888888888888(8.8(bar))
99=(891/9)=99(1-0.1(bar))=99-11.1(bar)=87.8888888888888888(87.8(bar))

If this is true, this screws up math.
USE THIS POWER WISELY

choube...@gmail.com

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Oct 4, 2018, 1:45:16 AM10/4/18
to
On Wednesday, September 19, 2018 at 9:34:42 PM UTC+5:30, b.a.ch...@gmail.com wrote:
> Sooo,
> 1=(9/9)=[1-0.1(bar)] = 0.9999999999999999...(0.9(bar))

Actually [1-0.1(bar)] = 0.8888888888888888...(0.8(bar)) and not 0.9(bar)

> 2=(18/9)=2(1-0.1(bar))=1.8888888888888888...(1.8(bar))

and 2(1-0.1(bar))= 1.7777777777777777...(1.7(bar))

If you meant 2*0.9(bar)
then 2*0.9(bar)= 1.9999999999999999...(1.9(bar)) and not 1.8(bar)
2*0.9 = 1.8,
2*0.99 = 1.98,
2*0.999 = 1.998,
2*0.9999 = 1.9998,
2*0.99999 = 1.99998 and so on.


> 99=(891/9)=99(1-0.1(bar))=99-11.1(bar)=87.8888888888888888(87.8(bar))
>

99*0.1(bar) = 10.9(bar) and not 11.1(bar)
similarly 99*0.9(bar) = 98.9999999999999999... = 98.9(bar)

> If this is true, this screws up math.

> USE THIS POWER WISELY
please do.

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