Naked Science Forum

General Science => General Science => Topic started by: Naufal the B. S. on 19/11/2009 14:29:57

Title: What is the result of 2/0?
Post by: Naufal the B. S. on 19/11/2009 14:29:57
I need it for school task. Please give explanation for this question
Title: What is the result of 2/0?
Post by: RD on 19/11/2009 15:28:15
If you are dividing by zero then you have probably made a mistake earlier in the calculation.
[anything divided by zero is gives an infinitely large answer: x/0 = ∞ (http://en.wikipedia.org/wiki/Infinity#Infinity_in_mathematics_and_logic) ]
Title: What is the result of 2/0?
Post by: JP on 19/11/2009 16:01:02
anything divided by zero is gives an infinitely large answer: x/0 = ∞ (http://en.wikipedia.org/wiki/Infinity#Infinity_in_mathematics_and_logic)

It depends how you define things.  Usually, dividing by zero isn't well-defined.  If you define the expression in terms of limits, then it could be infinite.
Title: What is the result of 2/0?
Post by: lightarrow on 20/11/2009 01:35:31
I need it for school task. Please give explanation for this question
You can't do it, it's not defined.
Title: What is the result of 2/0?
Post by: RD on 20/11/2009 23:11:46
I had a physics test.  The question was about that:

2000/0 = ?

my answer is 0. And that is true


0/2000 is 0, 2000/0 is ∞ ...

Quote
Another way to understand the nature of division by zero is by considering division as a repeated subtraction. For example, to divide 13 by 5, 5 can be subtracted twice, which leaves a remainder of 3 – the divisor is subtracted until the remainder is less than the divisor. The result is often reported as 13 ÷ 5 = 2 remainder 3.
But, in the case of zero, repeated subtraction of zero will never yield a remainder less than zero.
Dividing by zero by repeated subtraction results in a series of subtractions that never ends*
http://en.wikipedia.org/wiki/Division_by_zero

* i.e. infinite.
Title: What is the result of 2/0?
Post by: lightarrow on 21/11/2009 13:17:02
2000/0 doesn't exist.
You can make *the limit*:
lim     2000/x = +∞
x-->0+
Title: What is the result of 2/0?
Post by: JP on 21/11/2009 15:33:07
Lightarrow's correct.  Infinity is a concept, not a number, so you can't get it as an answer by simply dividing one number by another.
Title: What is the result of 2/0?
Post by: Naufal the B. S. on 22/11/2009 12:24:58
Ok... Thanks for all.

And the result, i am still smarter than my teacher.
Title: What is the result of 2/0?
Post by: JP on 23/11/2009 22:22:52
Just to play devil's advocate for a moment:

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

See the first equation.

(Of course, that "definition" requires that you are very careful about the meaning of infinity and that you're using complex numbers, and you still don't get it to behave like the rest of your numbers.)
Title: What is the result of 2/0?
Post by: kmiller755 on 24/11/2009 05:21:21
i agree with the above posters that it is a limiting process.

one question from me now, hopefully it doesn't derail this thread, but how did RD and lightarrow produce the infinity symbol in the post?
Title: What is the result of 2/0?
Post by: lightarrow on 24/11/2009 16:09:46
i agree with the above posters that it is a limiting process.

one question from me now, hopefully it doesn't derail this thread, but how did RD and lightarrow produce the infinity symbol in the post?
Click the "preview" button under the reply window and you'll get a lot of symbols and formatting instruments.
Title: What is the result of 2/0?
Post by: Matthews dad on 24/11/2009 20:46:51
So what is 2 x 0 ??   [???] [:-\] [:I]
Title: What is the result of 2/0?
Post by: lightarrow on 24/11/2009 23:14:02
So what is 2 x 0 ??   [???] [:-\] [:I]
Zero.
Title: What is the result of 2/0?
Post by: Jonathan Madriaga on 25/11/2009 22:22:29
it does not exist. You will get an error in your calculator. It equals infinity