Discussion about math, puzzles, games and fun. Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ π -¹ ² ³ °

You are not logged in.

- Topics: Active | Unanswered

Pages: **1**

**Ubergeek****Member**- Registered: 2009-07-14
- Posts: 205

Here:

http://www.math.com/students/wonders/life/life.html

http://www.halexandria.org/dward835.htm

*Philosophy is written in this grand book --*

*I mean the universe --*

*Which stands continually open to our gaze.*

*But it cannot be understood*

*Unless one first learns to comprehend the language*

*And interpret the characters in which it is written.*

*It is written in the language of mathematics,*

*And its characters are triangles, circles, and other geometric figures,*

*Without which it is humanly impossible to understand a single word of it.*

Galileo Galilei, Il Saggiatore (1623)

*Last edited by Ubergeek (2009-07-28 07:55:20)*

"Mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true."

Bertrand Russell

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,930

Hi Ubergeek;

**Thanks for the link.**

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

**Ubergeek****Member**- Registered: 2009-07-14
- Posts: 205

You're welcome.

"Mathematics may be defined as the subject in which we never know what we are talking about, nor whether what we are saying is true."

Bertrand Russell

Offline

**Denominator****Member**- Registered: 2009-11-23
- Posts: 155

Oh I know that game!

Its the irregular game of life !! Ididn't quite get it so I decided to play with it!! = ]

Woah the second link!!

Offline

**HowieHjones****Member**- Registered: 2010-01-22
- Posts: 1

cool

Offline

**thoughtdotcom****Member**- Registered: 2009-12-24
- Posts: 26

In regards to the second link, that actually works anytime you use .999....

for example:

N = 2.99...

(multiply both sides by 10)

10N = 29.99...

(subtract N from both sides)

9N = 27

(divide both sides by 9)

N = 3 = 2.99...

or

N = 0.7999...

(multiply both sides by 10)

10N = 7.999...

(subtract N from both sides)

9N = 7.2

(divide both sides by 9)

N = 0.8 = 0.7999...

*Last edited by thoughtdotcom (2010-01-24 08:53:35)*

I think, therefore you are.

Offline

**thoughtdotcom****Member**- Registered: 2009-12-24
- Posts: 26

help disproving 1=0.999....

ok, so this has been driving me nuts since I first saw it on the site. I understand that the mathmatical difference between 1 and 0.999.... is so minute as to make them practically the same thing, but they are not exactly the same. I can see the math is screwed up . . . well, it's more that I feel it, but I can't seem to disprove this yet. can anyone help?

I think, therefore you are.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,930

Hi thoughtdotcom;

is so minute as to make them practically the same thing, but they are not exactly the same.

First start here, they are not practically the same thing they are the same thing.

I can see the math is screwed up

The math is fine, you are using human common sense when you feel it is incorrect. Unfortunately lots of math is counterintuitive and sometimes seems to be wrong. That is an illusion.

but I can't seem to disprove this yet. can anyone help

Please, try to understand the proofs that you have seen.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

**thoughtdotcom****Member**- Registered: 2009-12-24
- Posts: 26

Thank you bobbym for replying. I was all set to leave this alone after your post, but a co-worker (we'll call him: Mr. Coffee) got himself involved. He believes that there is a problem in the step where we subtract x from each side of the equation. The way he puts it is: when you do something to one side of the equation, then you must do it to the other. So when we substitute 0.99... in for x on the right side of the equation, we must also substitute 0.99... for x on the other side of the equation. this gives us:

x = 0.99...

10x = 9.99...

10x - x = 9.99... - x

10(0.99...) - 0.99... = 9.99... - 0.99...

9 = 9

could someone look at this and tell me if it's correct, please. I'm anxious to know if Mr. Coffee has hit upon something, or not.

thanks.

I think, therefore you are.

Offline

**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,930

Hi thoughtdotcom;

Mr coffee hasn't done anything deep. This is how someone who's training is mostly discrete and numerical looks at it. Someone who can't discern the difference between rigor and rigor mortis.

1 = .9999999999999...

10 = 9.99999999999...

Subtract the top equation from the bottom:

9 = 9

Er spielt so einfach!

That convinced me a long time ago. Convince yourself now.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

Offline

Pages: **1**