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Is .999 repeating = to 1?
Yes.
33%
 33%  [ 5 ]
No.
46%
 46%  [ 7 ]
Who cares.
20%
 20%  [ 3 ]
Total Votes : 15


ochimaru

PostPosted: Sat Oct 01, 2005 12:21 am


This seems to be a really hot topic of debate amongst the math geeks these days. I miss school so much, I decided to take a crack at the debate myself. I, personally, support the fact that .999 repeating DOES = 1. Here is my theory, and for shits and giggles I threw in 2 SUPER geek theories from each side of the debate. Let's try not to get too heated about this, though, okay? I've seen blood shed over this topic. xd

's really a debate of infinite calculation vs. finite calculation. And secondly, real world usage of this principle.


Example 1:

Any decimal may be added to another decimal to make a whole number.

Whereas:
1 - x = y
1 - y = x

But:
x = .999 repeating
1 - x = .000 repeating

x = 1
1 - x = .000 repeating

therefore, .999 repeating = 1


Example 2 (Real World Application)

My second example is more logical. In reality, if you ever had an equation that came out to .999 repeating, you would NEVER get it correct. You would always be off by .000 repeating. Um, again proving the point above, but here saying you will always be off. Hence, in real world applications, we must make the number a finite number. And then .999 repeating will either equal 1 or equal .99... 8 depending on how exact the calculation is.


Example 3 (pirate quote)

Quote:
∞ != ∞
suggestion:
let f(x)=x
let g(x)=2x
what is the relationship between lim x->∞ f(x) and lim x->∞ g(x)? they are both ∞


Example 4 (pirate quote)

Okay, and just to be fair, here is a theory that supports why .999 repeating does NOT equal 1 using geometry.

Quote:
With invinite numbers no rounding is necessary.

proof 1: let .999... be represented by a geometric series 0.9 + 0.09 + 0.009 + 0.0009 + ...
a geometric series converges iff the ratio r satisfies 0r above =.1
the series converges
the sum of a converging geometric series is given by a/(1-r) where a is the first term and r is the ratio.
the sum above = 1

proof 2 (from emphy)
let sum (i=1,i=m) x(i) mean the sum of the series x(i)+x(i+1)+x(i+2)+...+x(m-2)+x(m-1)+x(m) from i=1 to i=m.

let epsilon (ep) be a real number 0let delta be the position of the first nonzero decimal place of ep
let M be a natural number > delta
let m>M
let f(m)=sum(i=1,i=m) 0.9^10(-i);

then f(m)> 1- ep

as ep approaches 0, f(m) approaches 1.



That one's ******** greek to me, but i understand the final answers. Graphically displayed it would be infinite. Like a fractal if you were zooming in to it from the side.


Dang, this only proves the philosophical nature of stoners. ha ha...
PostPosted: Sat Oct 01, 2005 6:40 am


Here we go, something I'm used to.

First of all, my response to your theory.

1/3 is .333 repeating, right? Well, triple that.

3/3 is apparently .999 repeating. But it's also 1, isn't it?

So .999 repeating = 1.

Also, 9/9 comes out to .999 repeating.

Cougar Draven


Contemplation

PostPosted: Sat Oct 01, 2005 11:32 am


I hate this kind of infinite mathematics
PostPosted: Sun Oct 02, 2005 1:10 pm


*head explodes* theoretical math drives me nuts

Socrates in Disguise
Captain


Rev Shrubbery

PostPosted: Tue Oct 04, 2005 6:54 am


Much easier reply:

There's an eigth grader at my school (a private school, at that) who is in 12th grade HONORS math. He's literally a progidy. Well, at the homecoming dance, he turned around and began explaining to me, out of the blue, that .999 repeating is equal to one.

Judging by the endless streams of logic he used which I'm far too lazy to repeat, as well as the math teacher's silent nods of approval, he's right.
PostPosted: Tue Oct 04, 2005 12:42 pm


Heh... wouldn't 1 also equal .9 repeating if .9 repeating equals 1?

(And... darn, the 1/3, 2/3, and 3/3 example has been used. stressed )

Thus... 1+1 could actually equal 1.9 repeating... right? (Maybe my math is off... sweatdrop )

Speaking of such... someone made an equation that proves females are evil.

Quote:
Girl = Time x Money
Time = Money
Girl = Money^2

Money = root of Evil
Money^2 = root of Evil^2

Thus...
Girl = Evil
blaugh
Innocent fun off my part.

User Image

aaarhus
Crew


ochimaru

PostPosted: Fri Oct 07, 2005 8:33 pm


aaarhus
Heh... wouldn't 1 also equal .9 repeating if .9 repeating equals 1?

(And... darn, the 1/3, 2/3, and 3/3 example has been used. stressed )

Thus... 1+1 could actually equal 1.9 repeating... right? (Maybe my math is off... sweatdrop )

Speaking of such... someone made an equation that proves females are evil.

Quote:
Girl = Time x Money
Time = Money
Girl = Money^2

Money = root of Evil
Money^2 = root of Evil^2

Thus...
Girl = Evil
blaugh
Innocent fun off my part.

User Image


Yes... it would.

And thanks for the girls are evil equation. I love that one. I actually just stumbled into it a few days ago and had a real good laugh. Geek humor. hah!

I wonder if the "floating point decimal" they talk about for graphics is somehow tied into this theory.
PostPosted: Sat Oct 08, 2005 7:35 am


Indeed, it does seem that 1 is equal to 0.999....
It seems to me that the only reason why this seems counter-intuitive is that one cannot really imagine infinity effectively.

I believe that "infinity" is not an actual number. It doesn't have an actual value. Saying that a digit is recurring seems to me to just show that the number cannot be accurately represented with our number system.

Mechanism


ochimaru

PostPosted: Sat Oct 08, 2005 5:14 pm


Infinity DOES have a value. It's "i"

i = square root of -1


One of the very few things that I retained from pre-calculus. What do I remember from trigonometry? Absolutely nothing... except that we had to program nearly everything into our monster TI-81 calculators and draw goofy graphs with sin, cosine and tangent. Outside of soundwaves, I truly have no comprehension of what the hell those functions do for me. I certainly have never had a real life application for them. I still remember the Quadratic Equation, too... again, no clue why the hell I'd ever use it in day-to-day life. You want to know the ONE equation that's been useful for day-to-day life?

x a
-- = --
y b

Balancing a related information. i.e. When your stupid timecard program calulates time in decimals & you need to convert it to minutes. I work .07 hours.

07 x
--- = ---
100 60

60 x 7 = 420
420 / 100 = 4.2 minutes


Don't have any clue what the technical name for that mathematical process is though...


Basic algebra has also come in handy a lot when using spreadsheets. But that's pretty damn basic stuff.
PostPosted: Mon Oct 10, 2005 6:51 pm


If the number is one then the number that it is equal to is either itself or .99 repeating. This is the conditional statement. According to you guys this is correct.

Here is the inverse of that statement

If the number is .99 repeating then that number is either equal to itself or 1.
This is correct because of both the reflective and symmetric property of equality.
.99=1 right? 1=.99 right?
But have you ever heard of any q implies p statement that works both symmetrically and reflectively? No you haven't. Because somewhere in that 3/3 is this 1/x plus repeating point nine where x if a multiple of 10. But lets compare .9 repeating to one. So here is the condtional statement again.

If the number is .9 repeating then it is equal to 1/x plus .9 repeating when x is a multiple of 10.

But the inverse however is...

If the number is 1/x plus .9 repeating when x is a multiple of ten then it is equal to .9 repeating.

Doesn't make sense does it? But this is even more wrong. An inverse doesn't have to be right in order for the conditional statement to be right also. If the conditonal statement is right then the contrapositive is right also and vice versa. Here is the contrapositive...

If the number is not .99 repeating then the number is not equal to itself or one.

Now that is just wrong. Zero is equal to itself and it is not .99 repeating.
And if the contrapositive is wrong then the condtional statement is wrong.

i standing for infinity? I don't think so. i stands for the value of a negative radical where applied to a electrical imaginary world. It stands for negative values of numbers when applied to that alternate mathematical dimension where I have no idea to explain. Here is proof that i does not stand for infinity...

i=.99999999... given
.99999...=3/3 or 1 ( i forgot what postulate this was called)
pi=i Pi goes on for infinity right it never ends.
pi=1 Transitive property of equality
so you are saying that 3.1415... is equal to 1? Wrong.

My conclusion... 3/3 is an unstable number, .9 repeating is a unstable number dodge if can. If not then the answer is undefined.




Now here is another debate question, why can't we divide by zero?.

If money is the root of all evil then girls are evil.

Prove= Girls are evil

Girl = Time + Money Girl Addition Postulate
Time = Money Time=Money Postulate
Girl = 2(Money) Subtitution property of equality

Money = root of all Evil Given
2(Money) = 2(root of all Evil) multiplication property of equality
Girl=2(root of all evil) Transitive property of Equality


Thsi is what is so great about philosophy! It can be stripped down to bare essentials and laws so that you can poke fun at other ideas and values! I blaugh u. I'm kidding. But philosophy is fun, you can just use if-then statements.

zenithal


Cougar Draven

PostPosted: Mon Aug 28, 2006 11:54 pm


zenithal
If the number is one then the number that it is equal to is either itself or .99 repeating. This is the conditional statement. According to you guys this is correct.

Here is the inverse of that statement

If the number is .99 repeating then that number is either equal to itself or 1.
This is correct because of both the reflective and symmetric property of equality.
.99=1 right? 1=.99 right?
But have you ever heard of any q implies p statement that works both symmetrically and reflectively? No you haven't. Because somewhere in that 3/3 is this 1/x plus repeating point nine where x if a multiple of 10. But lets compare .9 repeating to one. So here is the condtional statement again.

If the number is .9 repeating then it is equal to 1/x plus .9 repeating when x is a multiple of 10.

But the inverse however is...

If the number is 1/x plus .9 repeating when x is a multiple of ten then it is equal to .9 repeating.

Doesn't make sense does it? But this is even more wrong. An inverse doesn't have to be right in order for the conditional statement to be right also. If the conditonal statement is right then the contrapositive is right also and vice versa. Here is the contrapositive...

If the number is not .99 repeating then the number is not equal to itself or one.

Now that is just wrong. Zero is equal to itself and it is not .99 repeating.
And if the contrapositive is wrong then the condtional statement is wrong.

i standing for infinity? I don't think so. i stands for the value of a negative radical where applied to a electrical imaginary world. It stands for negative values of numbers when applied to that alternate mathematical dimension where I have no idea to explain. Here is proof that i does not stand for infinity...

i=.99999999... given
.99999...=3/3 or 1 ( i forgot what postulate this was called)
pi=i Pi goes on for infinity right it never ends.
pi=1 Transitive property of equality
so you are saying that 3.1415... is equal to 1? Wrong.

My conclusion... 3/3 is an unstable number, .9 repeating is a unstable number dodge if can. If not then the answer is undefined.




Now here is another debate question, why can't we divide by zero?.

If money is the root of all evil then girls are evil.

Prove= Girls are evil

Girl = Time + Money Girl Addition Postulate
Time = Money Time=Money Postulate
Girl = 2(Money) Subtitution property of equality

Money = root of all Evil Given
2(Money) = 2(root of all Evil) multiplication property of equality
Girl=2(root of all evil) Transitive property of Equality


Thsi is what is so great about philosophy! It can be stripped down to bare essentials and laws so that you can poke fun at other ideas and values! I blaugh u. I'm kidding. But philosophy is fun, you can just use if-then statements.


Feeling evil...math thread revival...::evil laugh::

Dividing by zero...always an intriguing idea. Let me posit.

1.) As a child, I was taught that you can divide by any number except zero, because it's impossible to divide a set amount of things into groups of zero. Of course, that, in and of itself, is a calculative problem. On paper, it can be worked around.

And I set about attempting to destroy the very fabric of the universe.

2.)

a=1;
b=1;
a=b;
a^2=b^2;
a^2-b^2=a-b;
(a+b)(a-b)=a-b;
a+b=1;
1+1=1;
1=0;

From there, you can prove anything. If we could bend reality to this, we could do so much more than we can now.

Perhaps this is the god scientists search for.
PostPosted: Tue Aug 29, 2006 7:10 pm


Based on my pathetic understanding of mathematics, I thought the purpose of 0.9 repeating was to purposefully define the number as LESS than one. Isn't the point of numbers that repeat is to make it clear that with each digit they get closer without ever reaching the next number?

~Ninja_Moo~


Cougar Draven

PostPosted: Wed Aug 30, 2006 2:07 am


~Ninja_Moo~
Based on my pathetic understanding of mathematics, I thought the purpose of 0.9 repeating was to purposefully define the number as LESS than one. Isn't the point of numbers that repeat is to make it clear that with each digit they get closer without ever reaching the next number?


Yes, I suppose that is the purpose. However...our mission as philosophers is more to question the ideas behind things, to expand that which we already know.



Found this link...says it all.

en.wikipedia.org/wiki/Proof_that_0.999..._equals_1

PostPosted: Sun Sep 10, 2006 8:23 pm


I still don't comprehend. What is the purpose of .9 repeating if it never has a use? When the hell are you going to use it? What is the point? Ooh... the most dangerous philosophy question of all. ha ha.


Oh, I think you got something Cougar! That could be the 'great simple equation that explains everything' that the physicists have been searching for. 1=0!! ha ha... so simple mathetmatically. But isn't that the same as everything=nothing?

everything = x
nothing = y

x - x = y
y - y = y
therefore x = y

rofl

ochimaru


Cougar Draven

PostPosted: Mon Sep 11, 2006 6:06 pm


ochimaru
Oh, I think you got something Cougar! That could be the 'great simple equation that explains everything' that the physicists have been searching for. 1=0!! ha ha... so simple mathetmatically. But isn't that the same as everything=nothing?


Well, yes, it is.

And although you might find it slightly amusing, think of it this way. If we can find a way to definitively divide by zero, we can therefore prove that 1=0...which then can be used to do anything. Ironically enough, I think that 1=0 is more useful in an alchemical situation. Y'know, changing of forms and whatnot. Just a curious idea....

This is what happens when I listen to DragonForce on an empty stomach while tired.
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