# .9 Repeating = 1 YES -or- NO

## Does .9 Repeating equal to 1?   116 members have voted

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Samoa

Ok pal

who put the seeds on the strawberry?

hint-nature did

Who put the red in Washington apples?

hint-nature did

Who put the freak in french fries?

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johngalt

lmfao - get ****y b/c you went back and read where I said

now, we substitute the values for the X into the equation and get another equation:

9.99999... - 0.99999... = ?

There is the big question - if you have an infinite series, and you subtract another infinite series from it, can you really say that the results are going to be entirely accurate?

at first glance, it looks like the infinite series of 9s following the decimal place will in fact negate, leaving you with a value of 9. However, again, a representation of infinite series with finite representation system. So, it is our inability to accurately represent .99999... as a true number that is the flaw in the system in the first place.

tough.

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Samoa

It's amazing you even tie your shoes. Cause ya didn't even answer the freakin question.

Ok let me make it simple for ya.

what's 9 times .9999 that's right 8.9991

What's 10 times .9999 that's right 9.9999

WHat's 9.9999-.9999 that's right 9

WHAT do you not understand?

x=.9999

10x-x=9x is not true

-"Cause there ain't no freak 'n french fries, that's what I've been trying to tell you butt breath"

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johngalt
It's amazing you even tie your shoes. Cause ya didn't even answer the freakin question.

Ok let me make it simple for ya.

what's 9 times .9999  that's right 8.9991

What's 10 times .9999  that's right 9.9999

WHat's 9.9999-.9999 that's right 9

WHAT do you not understand?

x=.9999

10x-x=9x is not true

-"Cause there ain't no freak 'n french fries, that's what I've been trying to tell you butt breath"

No, 9.9999... - .99999... is *not* equal to 9.

First of all, you are rounding off - my numbers are .99999..., which is *repeating*

So, when you multiply that value times 9, you get 8.99999... - also repeating nines, which you mentioned has a one carrying over - but if you remember your mathematics so well, then which digit do you start multiplying with? the largest, decimally speaking? uh, nope.

you start with the smallest. Now, with a series repeating, as in the 0.99999..., where is the smallest digit? Thereisn't one!!!!!!!

That is how the question is answered - you *cannot* do the multiplication here b/c the representation system that we use to represent a series of 9s after the decimal place is in fact flawed.

Sheesh.

Why do you think that I used the 1/3 = 0.33333... analogy instead? because, since there is no carry over, the multiplication was easier to visualize.

And Finally, I *did* answer your question - and every ones else's. I stated

Fundamentally, they are *not* equal - the series is *not* a representation of a true number, however, since there is no way to represent an infinite series using finite representations.

Oh, and as far as resorting to calling me names - don't go there. I am keeping the conversation and discussion civilized, and if you feel like losing your composure go to a flame room.

[edit - fixed some misspellings - boldfaced and italicized]

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johngalt

Oh ,and if you want to take a point up with my note of equivalency when regarding 0.99999.... as 1, go talk to *ANY* mathematics professor, teacher, or higher mathematics student. take my proof to them, and show me then what they say.

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Samoa
Oh ,and if you want to take a point up with my note of equivalency when regarding 0.99999.... as 1, go talk to *ANY* mathematics professor, teacher, or higher mathematics student. take my proof to them, and show me then what they say.

tell ya what, you take it to them. :yes: Cause you can't simply agree on anything. :sleep:

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itsnotabigtruck
.9999... is a none real number, 1 is a real number.

Actually, 9.99999... is a real number. All numbers are real numbers or they aren't numbers. You were saying that 9.99999... is irrational. That is not true either. An irrational number is a decimal neither repeating nor terminating. Since 9.99999... is repeating, it is indeed rational.

Natural numbers = {1, 2, 3...}

Whole numbers = {0, 1, 2, 3...}

Integers = {...-2, -1, 0, 1, 2...}

Rational numbers = all numbers expressable as "x over y"

Irrational numbers = all numbers NOT expressable as "x over y"

Real numbers = both the rational and irrational numbers

1 = natural, whole, integer, rational (1 over 1 = 1), real

0 = whole, integer, rational (0 over 1 = 0), real

-1 = integer, rational (-1 over 1 = -1), real

1.1 = rational (terminating decimal), real

1.11111... = rational (repeating decimal), real

sq.root of 5 = irrational (nonrepeating, nonterminating decimal), real

pi = irrational (nonrepeating, nonterminating decimal), real

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El Bourricot
Actually, 9.99999... is a real number. All numbers are real numbers or they aren't numbers.

What about complex numbers? They don't belong to |R yet they do exist (I suppose it's debatable what we mean by "exist").

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kjordan2001
It's amazing you even tie your shoes. Cause ya didn't even answer the freakin question.

Ok let me make it simple for ya.

what's 9 times .9999  that's right 8.9991

What's 10 times .9999  that's right 9.9999

WHat's 9.9999-.9999 that's right 9

WHAT do you not understand?

x=.9999

10x-x=9x is not true

-"Cause there ain't no freak 'n french fries, that's what I've been trying to tell you butt breath"

You're cutting off a lot of 9's there. You're assuming it ends, which it doesn't. It will keep making 9's forever. If you chop it off somewhere, of course you'll get a 1.

1/9 = .11111111111111111111111111111111111111111111111111111111111111111111 etc

8/9 = .88888888888888888888888888888888888888888888888888888888888888888888 etc

.888888888888888888888888888888888888888+.111111111111111111111111111111111111111111 = .999999999999999999999999999

This is true because for every 8 there is a 1.

8/9 + 1/9 = 1

.999999999999999999999999999999999999999999 = 1!

This is why when you can get things to fractions, use the fraction. Decimals suck, they hide too many things. You can't calculate these things in decimal. This is why pi is such a bitch and I don't understand why people want more than the thousands of decimal places we already have...they won't reach an end. They can fill up several thousand hard drives of numbers and still never reach and end.

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xEonBuRn

Its a calculus theory problem... those of you that haven't had calc should just stfu... and .9 repeating does equal 1.

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Samoa
Its a calculus theory problem... those of you that haven't had calc should just stfu... and .9 repeating does equal 1.

LOL you guys are so lame, .9999...does not equal one. :p

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ericnkatz

Quote from a friend from germany who is studying to be like a Astronaut, He is a jet pilot already and has taken many math type classes.

well,

our limited computer storage ranges, with certain layouts like Xbit float numbers (signed....M bits exponent of 2, X-M-1 bits body, 1 bit signum), limit mathematics in an unacceptable way.

so for each layout (X, M, signum) there is

- a biggest number

- a smallest positive number (less will be truncated to zero)

- a smallest number that gives a change if added to 1 (less will be truncated to 1)

therefor the "PC digits" argument doesnt count here.

however there is a quite simple proof for .999xN == 1 :

1. 1/9 == 0.111xN

2. 9 x 1/9 == 0.999xN

3. 9 x 1/9 == 9/9 == 1

thus

0.999xN ==1

If .999xN didn't == 1

It would null all math as we know it

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• 2 weeks later...
ambient

haha all you doubters, 1=0.9repeating

If you don't think it is, you don't understand infinity

You think of infinity as a ray (starting at a point but never terminating). This is true for something irrational like pi, which is simingly random, and can't be calculated exactly.

.9 repeating or anything repeating goes on forever, but not like a ray does. This type of infinity is like a ray that does in a circle, that doesn't end.

So if the 9s go to infinity, the value is infinitally precise, which means that is must equal 1. If it doesn't equal 1, what is it? what number is less than 1 but greater than .9999999999, a number of 9s that it takes to reach the end of a circle. BTW .00000repeating+1 at the "end" is impossible because a reapeating decimal HAS NO END!

the proof given works,

x=.9999999999.....

10x=(move the decimal place 1 to the left if you can't understnad it)9.99999999999.....

10x-x=9x

9.999999999999.....

-0.999999999999.....

all the 9s after the decimal cancell, and multiplying x by 10 IS CORRECT because it demostrats the concept of infinity, that infinity/infinity=infinity as it is not a number, multiplying by 10 loses no accuracy of the number, which already proves 0.99..=1

any way

=9=9x

there for x=1=.9999

you are not dividing then multiplying by the same number and getting a different number because you are then refuting that 1=.9999... without seeing the whole proof. This proof is like trying to open a safe where the key is inside, you can't find the soution until you have and accept some of the steps in finding it. Why is the no vote winning???

-sorry for typos, I wrote this in 5-10 minutes didn't proofread

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I read this and chuckled to myself. Does anyone understand this? I have a masters in various areas of English, Maths and Science, and this makes no sense.

First, Pi can be figured out, if the right mathematical and scientific equations were applied. You have to get the equations right first.

SECONDLY, and more importantly, you keep going on about rays, how can you compare mathematics to physics. You can't. The equal and opposite reactions that take place within the ray, among the atomic structures of the body which surrounds it, i.e. this could be air, works in a similar way to that of an electric signal along a copper wire. The ray degrades as a loss of energy builds, so it can not be used as a valid comparison in this question. I'm sure Mr. Astronut doesn't need me to tell him this but yes he is right about current computer storage abilities and the computer language itself. There are, no doubt floors in it. Defining the sum you so kindly showed us doesn't explain anything to those of us who are far less minded than Astronut. Also, using that sum, you get the same answer with a calculator. Which therefore contridicts what you previously stated.

Finally, this question is what is known as an unanswerable question. It's called that for a reason. No amount of science, maths or any other body of study is going to figure this out. All there is ever going to be is people who think too much, trying to explain it.

Edited by R002092
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....

Holy crap. Someone left the door to the nerdium open again.

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johngalt

r002092 - hence my explanation that this was a moot question, but that fundamentally, it is accepted in mathematics that .9 repeating is *equivalent* to 1.

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SaiKoR

The LIMIT of .99999999... is 1 but .999999... does not equal 1

this is a similar thing as the limit as x->infinity of 1/x is 0 BUT 1/x can NEVER equal 0.

All the "proofs" presented here assume that there is an end to the number, which as it is a recurring decimal, there IS no end to it. It's a similar thing to, 2x infinity subtract infinity. does that equal infinity? i think not. Inifinity is NOT a number. it's a concept, one which humans have a lot of trouble grasping. a reccuring decimal has an infinite number of decimal places and therefor (as infinity is not a number) you can NOT subtract .9999999... from 9.999999

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OPaul

Ironic isn't it, just like .9999.. never ends neither does this thread, stop resurrecting it just to say the same thing someone has already said.

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ambient

First of all, before you judge others writing, its should be math, not maths, the plural is in masters, and you can't use "a" before something that is plural.

I highly doubt you have any proof that PI can be figured out, it is the irrational ratio of a circles diameter to its circumference, and you can't find an irrational value using rational equations. I have seen some equaltions that do not terminate and eventually their limit is pi, but that doesn't give an "exact value" of pi.

It seems that you have overlooked simplicity, When I say ray I mean the geometrical idea of a line that starts and a point and goes to infinity. I know that there are errors in what a said, I didn't take the time to try to fix it

Go ahead and critic my grammar, but know I am not trying to write a perfect post.

And until you can disprove the proofs given, the question is answerable, because a answer is proven.

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John

christ, this thread is still going? :blink: give it up people, it's NOT 1 :laugh:

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rob.derosa
christ, this thread is still going? :blink: give it up people, it's NOT 1 :laugh:

Oh, but it is :laugh:

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First of all, before you judge others writing, its should be math, not maths, the plural is in masters, and you can't use "a" before something that is plural.

I did not comment on anyones writing, just the comments made within.

Firstly I really hate correcting peoples grammar, but here I go.

First of all I would like to admit to you ambient that yes there was an error within my statement, but that error was within the punctuation and nothing more, The 'a', you so kindly pointed out, is susposed to be there, as I did not say I have master's degrees, then the a would not have been necessary. The apostrophe was missing and that was it. Maths is correct. I'm sure if you look it up in any English dictionary, the word math does not exist. Math is in fact American, so therefore you are wrong and I am correct. Again.

But because of the stability of proof which has been given, there is no basis on which anyone can confidently say that 0.99999 etc. is in fact one.

Now back to the subject at hand. As johngalt so kindly pointed out, it is excepted within mathematics, that 0.9999 etc. = 1. I believe that the question asks as to whether or not it is 1, not whether or not it is accepted.

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I just decided I like SaiKoR's comment, because it points out what I've been saying beautifully, except in a way that everyone else should understand, not meaning to offend anybodies intelligence.

A very valid point to make, that infinity is a concept, not a number so therefore, in some form, void the question.

Bravo

Edited by R002092
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ambient

If you say that is is = to 1, why would you even post to say that it is unanswerable, as it seems your posts are oriented towards if it is acccepted or not, yet you say thats not the question

But because of the stability of proof which has been given, there is no basis on which anyone can confidently say that 0.99999 etc. is in fact one.

Please explain what exactly you mean here, you are not even examining the proof, you are just saying that you think those who don't believe .9999 =1, maybe uncertain.

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If you read the sentence correctly, you would establish that I never actually said that 1 = 0.999 etc., or in fact that it didn't. I have only said, and agreed with another comment made, that it is accepted in mathematics that 0.999 = 1. There is no valid evidence which will prove the answers given are in fact correct. If someone can prove to me that it is 1, which I doubt will happen, then I will be totally convinced; But until such time as it is proved, in a plausible and understandable manner, I will say that is does not equal 1.

I hope this explains my comments.

If not, I've run out of ideas and comments. I already feel like I've written this 3 times.