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1. Ok here is an interesting question.

-0 -> 0 divided by anything is 0 right??

BUT

-1 -> anything divided by itself is 1...

but also

-infinity (or undefined) -> anything divided by 0 is infinity or undefined...
2. You can't divide by 0, its mathematically impossible
3. (Original post by DLS)
You can't divide by 0, its mathematically impossible
even if it is itself? nah this is just a question i would like to see people answer (i actually do know the answer and it isn't just you can't divide by 0)
4. There is no such thing conceptually as a division by zero.
5. It is indeterminate. 0/0 means "What do you multiply zero by to get zero?"
6. Dividing by zero is something deemed impossible. However this can be then be elaborated against using complex numbers.
7. division by 0 doesn't exist across the complex set, just as square rooting negatives doesn't exist across the real set
8. Actually the answer ins't that you cannot divide by 0, but that it really is undefined, there is no true answer as there are no boundaries to the question
9. (Original post by theBOON)
However this can be then be elaborated against using complex numbers.
No it can't
10. Whatever answer you heard other than that it's impossible was wrong I think.
11. (Original post by zdo0o)
division by 0 doesn't exist across the complex set, just as square rooting negatives doesn't exist across the real set
Division by 0 cannot occur in any field
12. (Original post by Rick-Raith)
Ok here is an interesting question.

-0 -> 0 divided by anything is 0 right??
No. 0 divided by anything is 0 except when dividing by 0

(Original post by Rick-Raith)
BUT

-1 -> anything divided by itself is 1...
Again, untrue unless with "except 0"

(Original post by Rick-Raith)
but also

-infinity (or undefined) -> anything divided by 0 is infinity or undefined...
There you go.
13. Division by zero is NOT DEFINED!
14. (Original post by SimonM)
Division by 0 cannot occur in any field
Clearly you are uneducated in the ways of the single greatest mathematician of our time; some moron maths teacher from Berkshire

http://www.bbc.co.uk/berkshire/conte..._feature.shtml

Far from letting the fact that "you can't do it you idiot" deter him, he went ahead and taught it to his year 10s! What a hero.
15. To repeat other posters, division by zero is not allowed.
But if we could use infinity in arithmetic (which we can't, otherwise we can get to conclusion like 1=2) then obviously (x)(0)=0 so 0/0=x so 0/0 can equal anything really.

Another way of thinking of it is this:
ab
=a(1+1+1+1...)
=a+a+a+a...
where there are b 1's in the second line and b a's in the last.
So , for example, we would need 10 6's in (6+6+6....) to get (10)(6)=60.
Now obviously a(0)=0, i.e. (0+0+0...) where there are a 0's. Now no matter how many times you add 0, and therefore no matter how big a is, if we were to divide both sides by 0, which we would only do if we were not quite sober, then we see a=0/0 and as before a is an arbitrary number so 0/0 can equal anything (similar argument to before).

The concept of infinity relates to the question how many 0's do we need to add to get 1 (or 2, or 3, or 0.000001, or 503)? It seems no matter the number of zeros there are, you will not get far, even in an infinite amount of time. So we need an inexpressibly large ever-increasing boundless number which we call infinity. Being boundless means we cannot use it arithmetic. We can use 99999999999....999^999999999999. .........999 but not infinite.
16. (Original post by zdo0o)
Clearly you are uneducated in the ways of the single greatest mathematician of our time; some moron maths teacher from Berkshire

http://www.bbc.co.uk/berkshire/conte..._feature.shtml

Far from letting the fact that "you can't do it you idiot" deter him, he went ahead and taught it to his year 10s! What a hero.
I doubt even he would argue that it was possible in a field
17. (Original post by zdo0o)
Clearly you are uneducated in the ways of the single greatest mathematician of our time; some moron maths teacher from Berkshire

http://www.bbc.co.uk/berkshire/conte..._feature.shtml

Far from letting the fact that "you can't do it you idiot" deter him, he went ahead and taught it to his year 10s! What a hero.
I don't think you are getting the point. He is arguing for a fixed representation of 0/0 in the IEEE float standard in computation which in some cases would be intuitive/useful (similar to how 0^0 defaults to 1 in most programming languages). In no way is he actually saying analytically 0/0 would be defined in mathematics.
18. (Original post by Rick-Raith)
Ok here is an interesting question.

Oh, Jesus WEPT. Not this again.

It is not an interesting question. As everyone has noted, there is no answer, aka "the answer is undefined" aka "you can't divide anything by zero". As for your later comment that you know the answer and it isn't "you can't divide by zero", you are talking utter molluscs.
At the risk of repeating everyone else: division is defined as the inverse of multiplication. "15/5" means "the unique number that, when multiplied by 5, gives 15". "0/0" means "the unique number that, when multiplied by 0, gives 0". Any number at all works, therefore there is no unique number, therefore 0/0 is undefined. Similarly "x/0" for any non-zero x means "the unique number that, when multiplied by 0, gives (non-zero) x". In this case there is NO such number, so again the result is undefined.

Various people have attempted to make division by zero possible. They are either idiots who don't know OR WANT TO KNOW how maths works, or highly knowledgeable professional mathematicians who make it possible by redefining what "0" or "/" mean in the context of their paper.
Here's one that I don't pretend to understand, though I'm familiar with the most basic ideas of abstract algebra.

ETA: wow, I just noticed the publication date of that paper I linked to. Feel free to make an extremely tasteless "OMG you just divided by zero!!!!" joke out of it.
19. (Original post by zdo0o)
Clearly you are uneducated in the ways of the single greatest mathematician of our time; some moron maths teacher from Berkshire

http://www.bbc.co.uk/berkshire/conte..._feature.shtml

Far from letting the fact that "you can't do it you idiot" deter him, he went ahead and taught it to his year 10s! What a hero.
haha making up a new number to solve a problem... like you said, what a hero!

edit: and:
"Imagine you're landing on an aeroplane and the automatic pilot's working," he suggests. "If it divides by zero and the computer stops working - you're in big trouble. If your heart pacemaker divides by zero, you're dead."

Programs that involve risk i.e. autopilot surely involve code to prevent/catch a division by zero. I do it on my a level computing coursework, I'd imagine programmers working in those fields are well aware x/0 cannot be done/will cause a crash. I'm sure its a problem already solved in that respect no?
20. (Original post by SimonM)
No it can't
Complex numbers can be extended to a "wheel" in which case division by zero returns a numeric value.

Also in computer arithmetic division by zero returns a value.

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