0.9999... = 1? WHERE is it?

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Kyteland

Diamond Member
Dec 30, 2002
5,747
1
81
Originally posted by: bleeb
Thanks Kyteland for creating that thread!

I thoroughly enjoyed arguing with that one. Too bad the bastard who NEFFED the thread to lock. BOO!!

You're very wlecome.

I have no idea how I missed this thread the first time around.
 

spidey07

No Lifer
Aug 4, 2000
65,469
5
76
Originally posted by: episodic
.9999 does not equal one - no matter how many 9's there are. . .

yes, yes it does (if repeating) and can be proven so in about 10 different ways. We'll get back to the "obviously you don't understand math" if you think that it doesn't arguement.

they are one and the same. Equal.
 

BRObedoza

Diamond Member
Apr 16, 2004
4,133
0
76
We went over the proof of this the other day in Advanced calc. There's a theorem on decimal expansion that proves its true.
 

bleeb

Lifer
Feb 3, 2000
10,868
0
0
0.9999... != 1...

from a visual perspective.... a bunch of nines on one side, a one on the other.

Also everyone THINKS it is exactly one but it isn't... they've only proven that the behavior of 0.9999... towards infinity behaves like one. Just because it behaves like one, doesn't mean that it is. >=)

Ponder that!
 

TechnoKid

Diamond Member
Feb 12, 2001
5,575
0
0
Originally posted by: bleeb
0.9999... != 1...

from a visual perspective.... a bunch of nines on one side, a one on the other.

Also everyone THINKS it is exactly one but it isn't... they've only proven that the behavior of 0.9999... towards infinity behaves like one. Just because it behaves like one, doesn't mean that it is. >=)

Ponder that!

my math professor today showed a pretty convining example. 1/3 is equalt to .3333 repeating, (1/3)*3 is equal to one...... .333R times three is .99999R so its equal to one???

I still don't think an infinite series such as .9999R can be equal to a finite number 1.

.9999R is equal to the sigma of (9/(10^n)) starting at 1 and going to infinity.
 

chuckywang

Lifer
Jan 12, 2004
20,133
1
0
Originally posted by: bleeb
0.9999... != 1...

from a visual perspective.... a bunch of nines on one side, a one on the other.

So 1+1 != 2 cause there's a bunch of ones on one side and a two on the other?
 

TuxDave

Lifer
Oct 8, 2002
10,571
3
71
Originally posted by: bleeb
0.9999... != 1...

from a visual perspective.... a bunch of nines on one side, a one on the other.

Also everyone THINKS it is exactly one but it isn't... they've only proven that the behavior of 0.9999... towards infinity behaves like one. Just because it behaves like one, doesn't mean that it is. >=)

Ponder that!

Ok... I see where you're going. How about this as a question. Does 0.999... hold an equal numerical value as 1?
 

Howard

Lifer
Oct 14, 1999
47,982
11
81
Originally posted by: TuxDave
Originally posted by: bleeb
0.9999... != 1...

from a visual perspective.... a bunch of nines on one side, a one on the other.

Also everyone THINKS it is exactly one but it isn't... they've only proven that the behavior of 0.9999... towards infinity behaves like one. Just because it behaves like one, doesn't mean that it is. >=)

Ponder that!

Ok... I see where you're going. How about this as a question. Does 0.999... hold an equal numerical value as 1?
You can't help him; over a thousand posts in the previous thread couldn't.

Unless he's trying to do the same thing with this thread as the last.
 

episodic

Lifer
Feb 7, 2004
11,088
2
81
if you have .9999999999999999999999999999999999999999999999999999999999999999999999999999 of a pound - a pound is still a hair more. . ..
 

TuxDave

Lifer
Oct 8, 2002
10,571
3
71
Originally posted by: episodic
if you have .9999999999999999999999999999999999999999999999999999999999999999999999999999 of a pound - a pound is still a hair more. . ..

You're missing roughly an infinite number of 9s at the end of that chain.
 

episodic

Lifer
Feb 7, 2004
11,088
2
81
Originally posted by: TuxDave
Originally posted by: episodic
if you have .9999999999999999999999999999999999999999999999999999999999999999999999999999 of a pound - a pound is still a hair more. . ..

You're missing roughly an infinite number of 9s at the end of that chain.




It doesn't matter - stop at any place along that infinite chain - and there will be slightly more on the one side . ..
 

TuxDave

Lifer
Oct 8, 2002
10,571
3
71
Originally posted by: episodic
Originally posted by: TuxDave
Originally posted by: episodic
if you have .9999999999999999999999999999999999999999999999999999999999999999999999999999 of a pound - a pound is still a hair more. . ..

You're missing roughly an infinite number of 9s at the end of that chain.




It doesn't matter - stop at any place along that infinite chain - and there will be slightly more on the one side . ..

Yeah.. if you STOP in the chain there will be more stuff on one side. But what if you're not stopping anywhere.
 

episodic

Lifer
Feb 7, 2004
11,088
2
81
Originally posted by: TuxDave
Originally posted by: episodic
Originally posted by: TuxDave
Originally posted by: episodic
if you have .9999999999999999999999999999999999999999999999999999999999999999999999999999 of a pound - a pound is still a hair more. . ..

You're missing roughly an infinite number of 9s at the end of that chain.




It doesn't matter - stop at any place along that infinite chain - and there will be slightly more on the one side . ..

Yeah.. if you STOP in the chain there will be more stuff on one side. But what if you're not stopping anywhere.



So how are you going to find out then? If you don't stop the chain you can't end a calculation . ..
 

TuxDave

Lifer
Oct 8, 2002
10,571
3
71
Originally posted by: episodic
Originally posted by: TuxDave
Originally posted by: episodic
Originally posted by: TuxDave
Originally posted by: episodic
if you have .9999999999999999999999999999999999999999999999999999999999999999999999999999 of a pound - a pound is still a hair more. . ..

You're missing roughly an infinite number of 9s at the end of that chain.




It doesn't matter - stop at any place along that infinite chain - and there will be slightly more on the one side . ..

Yeah.. if you STOP in the chain there will be more stuff on one side. But what if you're not stopping anywhere.



So how are you going to find out then? If you don't stop the chain you can't end a calculation . ..

Just because the decimal representation of a number does not stop, does not mean it cannot hold a value. Look at sqrt(2). There's no finite decimal representation but it's still equal to something.

 

mobobuff

Lifer
Apr 5, 2004
11,099
1
81
Oh crap, a search for it spawned another one. Please stop now! This argument is infinity in itself.
 

TuxDave

Lifer
Oct 8, 2002
10,571
3
71
A proof that's been tossed around many many times.


x= 0.999....
10*x=9.999....
10*x-x=9.999...-0.999... = 9
9x = 9
x = 1

0.999... = 1

QED!!!
 

Koing

Elite Member <br> Super Moderator<br> Health and F
Oct 11, 2000
16,843
2
0
wtf this up again?!

I was only trying to find the original one and that I did. Then this ones turns up again a few months later!

Koing