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0 or does not exist?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**anonimnystefy****Real Member**- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,015

Yes, it is 0. Why should it not exist?

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**phanthanhtom****Member**- Registered: 2012-06-22
- Posts: 290

Yup. It is 0. Probably you mean there should be a sign (negative or positive) for infinity? Not needed in this case.

*Last edited by phanthanhtom (2013-06-16 02:25:18)*

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OK

∞ or does not exist?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

Hi;

I would say ∞.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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**phanthanhtom****Member**- Registered: 2012-06-22
- Posts: 290

it is infinity.

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But isn't it different from different directions??

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

That is very good, I always forget that. You are correct. It is undefined.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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**{7/3}****Member**- Registered: 2013-02-11
- Posts: 210

The second limit does not exist,it would exist if absolute value was used.

There are 10 kinds of people in the world,people who understand binary and people who don't.

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Or if the denominator was x[sup]2[/sup]

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

Then I would say it is infinity, because it has the same limit from both sides.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.** **A number by itself is useful, but it is far more useful to know how accurate or certain that number is.**

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Yes. I was adding an option to post 9 actually

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

Mathematica believes the first limit is infinity. Something about a projective plane...

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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OK but my কলনবিদ্যা (pronounced something like "Kalanbidya" meaning Calculus) book does not agree that #4 is infinity

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

Which one is number 4?

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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**{7/3}****Member**- Registered: 2013-02-11
- Posts: 210

The limit would also exist,if it was one sided limit.

There are 10 kinds of people in the world,people who understand binary and people who don't.

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Agnishom wrote:

OK

∞ or does not exist?

This is number 4

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

Oh yes, I would say it is undefined. I was just mentioning that M does not agree. The Wiki page explains why but I do not understand.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Could you please provide a link?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

http://en.wikipedia.org/wiki/Limit_of_a_function

It starts with this line:

In contrast, when working with the projective real line, infinities (much like 0) are unsigned, so, the central limit does exist in that context:

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Which do you not understand?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 104,203

The whole thing about why that limit now exists.

**In mathematics, you don't understand things. You just get used to them.****If it ain't broke, fix it until it is.**

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Does it exist?

'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'

I'm not crazy, my mother had me tested.

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**{7/3}****Member**- Registered: 2013-02-11
- Posts: 210

In projective space there are 2 points at infinity in any direction,since 2 lines intersect in one point and a parallel line intersects both points at infinity,the two points are considered same,thus in case of real projective line infinity and nagetive infinity are the same points and the limit is simply infinity(or minus infinity,doesn't matters cause they're same)

*Last edited by {7/3} (2013-06-16 16:38:01)*

There are 10 kinds of people in the world,people who understand binary and people who don't.

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