Is 1 = 0.9999......

[hdeck]

*not wasting my time reading through the previous 500 posts*

1 is a rational number. 0.999... is not. therefore they are not equal.

 

[bleeb]

Originally posted by: SilentRunning

Originally posted by: bleeb
Please don't let this thread die!

It was dead before it ever started


Bleeb, is this the only email you get

What do you mean it was dead before it started? This thread is still alive! Like the survivors that crashed into the andies mountains, you know.. the soccer team that ate each other to survive and had a movie based on it called "Alive" ... Anyways, Happy Doodles~!

 

[Kyteland]

Originally posted by: SilentRunning

It is all your fault

and.....

SilentRunning is a caveman with a loaded weapon, he has sufficient knowledge of math to make himself dangerous, unfortunately he does not have the depth of understanding he believes himself to have.
--RossGr

Don't assume malice for what stupidity can explain.

Those two tag lines go together so well. RossGr likes his verbal attacks.

:Q I actually didn't notice that. I thought it was kinda funny and figured I needed a good SilentRunning quote to add to my sig so...

Anyway, *poof* fixed.

 

[silverpig]

Originally posted by: hdeck
*not wasting my time reading through the previous 500 posts*

1 is a rational number. 0.999... is not. therefore they are not equal.

0.999... is in fact rational.

 

[james88]

not reading the 500 post

I say 1 is = 0.9999...

base on this prove( I sure someone wrote this prove already because it is so common)

1/3 + 1/3 + 1/3 =1
or
.333... + .3333... +.333.. =.999...
1/3 = .333...

therefore .999.. = 1.

 

[Shimmishim]

Originally posted by: james88
not reading the 500 post

I say 1 is = 0.9999...

base on this prove( I sure someone wrote this prove already because it is so common)

1/3 + 1/3 + 1/3 =1
or
.333... + .3333... +.333.. =.999...
1/3 = .333...

therefore .999.. = 1.

I have to agree here....

but the question is.... what is .99999 repeating as a fraction... cuz it can't be 3/3....

so maybe they're not equal... ARGH... I HATE MATH!!!

 

[PTCvette]

ya know, I hate this crap. Over the summer my college algebra teacher tried to tell us this, and I told him that I didn't give a crap about proofs and stupid garbage like that and never went back to the class. Good thing it was during the whole drop/add time so I got out while I could. I think he just wanted to try and look cool or something, but it annoyed the crap out of me!

 

[silverpig]

Originally posted by: Shimmishim

Originally posted by: james88
not reading the 500 post

I say 1 is = 0.9999...

base on this prove( I sure someone wrote this prove already because it is so common)

1/3 + 1/3 + 1/3 =1
or
.333... + .3333... +.333.. =.999...
1/3 = .333...

therefore .999.. = 1.

I have to agree here....

but the question is.... what is .99999 repeating as a fraction... cuz it can't be 3/3....

so maybe they're not equal... ARGH... I HATE MATH!!!

0.999... as a fraction is 1/1. Read the rest of the thread, I've posted how it works a few times.

 

[MadRat]

x = (y - 1) / y

Solve for "x", where "y" = infinite.

Edit: The symbol for infinity ("??") isn't supported

 

[silverpig]

x = y/y - 1/y

x = 1 - 1/y

Now, you can't exactly do the math by treating infinity as a number, but you can let z = f(y) = 1/y and let u = lim (y->inf) z. Then you have:

x = 1 - f(y)

x = 1 - z

x = 1 - lim(y->inf) z

x = 1 - 0

x = 1

 

[RIGorous1]

The answer is NO ofcourse....

Here's my reasoning:

does 1 = .9 no
does 1 = .99 no
does 1 = .999 no
does 1 = .9999... Uh no

ok so you guys are thinking duh stupid, but here is the fundamental error in the first's post logic: he multiplied a FINITE number by an infinite number and assumed that (.9999... - .999... ) = 0 when by definition an infinite number does not end, so how can subract infinity from infinity? infinity - infinity = undefined. The question is not so much a mathematical problem, but a logic problem and by what definitions you attribute to different symbols.

Finite x infinite = illogical - that is your problem. These type of problems were delt with in my math 351 class- Advanced number systems and logic.

Rig

Edit: for those of you who are using calculus to approximate this answer you are making the same mistake as the poster of this thread. Infinite and limits are the same concept, you can't multiply finite numbers by infinite numbers because that's where your dead.

 

[james88]

RIGorous1 said:

you can't multiply finite numbers by infinite numbers because that's where your dead.

but 1/3 is not infinite number right? therefor .333... is not an infinite number right? so is .9999... right?
Therefore you can multiply by 3 right? so therefore 3 X 1/3 =1. (but whom an I to say, you take an higher math class than me!)

What do you think, RIGorous1?


infinity is so hard to grasp!
argh!

 

[silverpig]

You're not subtracting, adding, muliplying or dividing infinity at all here.

Infinity > 2, yet neither of these numbers are larger than 2. There is no way we're doing anything with infinity itself.

We are, however, dealing with an infinite number of digits, but we do that all the time. There's nothing wrong with it.

 

[RossGr]

Finite x infinite = illogical - that is your problem. These type of problems were delt with in my math 351 class- Advanced number systems and logic.

I assume you got at best a C for effort, as you surely did not learn much, then agaiin this is one of math courses for CS majors and you kind of have to spoon feed them. Perhaps they just didn't bother presenting a full analysis couse. SilentRunning must have been in the same course.

go back a coulple of pages and examine my proof, show were I multiplied a number by an infinte number of digts, show me where I evaluated to a number an addtion or substraction which had a carry over to infinity. I did none of these "errors" yet still managed to prove that .99... =1. The reason I was able to do that is because mathematically they are equal. There is no approximation involved. An approximation occurs when you chop off and ignore the remainder of an infite string.

Your couse by the way, was not a course in real analysis, I am sure they touched on the topic, and showed you that truncating numbers results in approximation, you then took that to mean all numbers are approximations. This is simply not the case.

 

[MadRat]

That same proof RossGr had to edit when SilentRunning, the modest mathematician, showed him his gaff.

 

[silverpig]

Originally posted by: MadRat
That same proof RossGr had to edit when SilentRunning, the modest mathematician, showed him his gaff.

Typo dne logic flaw...

 

[MadRat]

Originally posted by: silverpig
x = y/y - 1/y
x = 1 - 1/y
Now, you can't exactly do the math by treating infinity as a number, but you can let z = f(y) = 1/y and let u = lim (y->inf) z. Then you have:
x = 1 - f(y)
x = 1 - z
x = 1 - lim(y->inf) z
x = 1 - 0
x = 1

Wrong. You forget that with a simple equation like this we have no need to use limits.

We are doing basic math. The same basic math that makes up any fraction. You just want to pursue it in calculus because it sounds complicated, don't you?

 

[silverpig]

I did it with limits to show what answer you get...

note: infinity/infinity is actually an indeterminate form, but seeing as how it's y/y, you can say it is 1.

 

[axelfox]

I would say no, because if it was, why would need a .99-->

?

 

[RossGr]

That same proof RossGr had to edit when SilentRunning, the modest mathematician, showed him his gaff.

Silentrunning did not point out the typo. If he was half as sharp as he thinks he is he would have seen it for what it is and been able to point it out but he didn't. I found it on my own, and btw still have not posted a corrected verision.

Madrat, your have referred to me editing things several times, not sure what you are talking about, If I make a content change I mark it as an edit, If I correct a typo (who?? Me, I never make typos! LOL) the edit will be within minutes of the original post and may not be noted.

As far as math skills go Silentrunning has plenty of reason to be modest.

 

[dighn]

geez so many ppl voted no. i hoe they are kidding

 

[VFAA]

Here's an example:

99.99% of the time 0.999 = 1.0

Hey, even 0.95 is rounded up to 1.0

 

[Skyclad1uhm1]

Originally posted by: silverpig
x = y/y - 1/y

x = 1 - 1/y

Now, you can't exactly do the math by treating infinity as a number, but you can let z = f(y) = 1/y and let u = lim (y->inf) z. Then you have:

x = 1 - f(y)

x = 1 - z

x = 1 - lim(y->inf) z

x = 1 - 0

x = 1

So you are saying that, were you to draw y = 1/x you would draw it as reaching 0 rather than approaching it? The limit is never reached, that is what it is a limit for in the first place.

 

[RossGr]

LIm (x-> infinity) 1/x = 0

What else is could it be, that is purpose of taking limits.

 

[RossGr]

Originally posted by: VFAA
Here's an example:

99.99% of the time 0.999 = 1.0

Hey, even 0.95 is rounded up to 1.0

100% wrong, .999 <> 1 never has been never will be.