Can x/0 be divided out


by ShawnD
Tags: divided, x or 0
ShawnD
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#1
Apr2-04, 02:01 PM
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Say I had an expression that went like this

[tex]\frac{ 5 \frac{x}{0} }{3 \frac{x}{0} }[/tex]

Can I divide those [itex]\frac{x}{0}[/itex] terms or do they make the expression undefined?
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chroot
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Apr2-04, 02:04 PM
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Nope, you can't divide them out. The entire expression is indeterminate (NOT undefined).

- Warren
matt grime
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Apr2-04, 05:42 PM
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I wouldn't say you can't divide them out so much as what you wrote is just plain wrong, being polite about it - the symbols make no sense as written.

chroot
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Apr2-04, 06:08 PM
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Can x/0 be divided out


I think he means

[tex]\frac{ 5 \cdot \frac{x}{0} }{3 \cdot \frac{x}{0} }[/tex]

to be read "5 times x over 0...", not "5 and x zeroths..."

- Warren
matt grime
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Apr3-04, 04:29 AM
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But is still makes no sense. x/0 is not a well-defined symbol in the real number system that one can manipulate like this.
Chen
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Apr3-04, 06:35 AM
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I think that was part of his question.
Organic
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Apr3-04, 07:12 AM
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1/0.1 is tha same as 1*10
1/0.01 is tha same as 1*100
1/0.001 is tha same as 1*1000
and so on ...

1/0 is the same as 1*oo and in both cases we are no longer in a finite system.

oo is a general notation for infinity therefore 1/0 is also a general notation for infinity.

Please look at: http://mathworld.wolfram.com/Infinity.html
Zurtex
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Apr3-04, 10:38 AM
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Quote Quote by Organic
1/0.1 is tha same as 1*10
1/0.01 is tha same as 1*100
1/0.001 is tha same as 1*1000
and so on ...

1/0 is the same as 1*oo and in both cases we are no longer in a finite system.

oo is a general notation for infinity therefore 1/0 is also a general notation for infinity.

Please look at: http://mathworld.wolfram.com/Infinity.html
Note for others, in the link given it goes points out:

"Informally,[itex]1 / \infty = 0[/tex] , a statement which can be made rigorous using the limit concept"

You can't just say:

[tex]\frac{1}{\infty} = 0[/tex]

or any manipulation of that as and think it is mathematically true.
Hurkyl
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Apr4-04, 12:30 PM
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Discussion over the foundations of limits split to new thread. Please stop hijacking threads.


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