Sorry I could'nt find the link and forgot to bookmark it. But, this question came up and was posted recently. So I asked my dad who has a PHD in mathamatics and teaches physics. I asked him what the current take on zero is in the math world as pertaining to this particular problem. So here is the original question and his answear to the problem.
> An interesting mathematical dilemma:
>
> 0/0=?
>
> Three absolutes (as I was taught):
>
> Anything divided by zero is undefined
> Zero divided by anything is zero
> Anything divided by itself is one
>
> What is your opinion on this? (give reasons)
Division is defined in terms of multiplication which is an "assumed" operation unless you are studying set theory where number, addition, and multiplication are defined.
For any three real numbers, a/b = c if and only if bc = a. For example 8/2 = 4 because 2(4) = 8 , in other words, it checks.
Now suppose a = 8 and b = 0 and suppose that 8/0 = c where c is some real number. Then 0(c) = 8 since it must check. However, 0(any real number ) = 0. Now both properties cannot be true. Either we can't have an answer to any non-zero number divided by zero or we can have the property that 0 times any number is zero. Mathematicians faced this choice years ago and decided that 0 times any number equals zero is the more valuable property in the real number system. Consequently, division on a non zero number by 0 is not defined.
What about 0/0? Suppose we say 0/0 = c where c is some real number. Will it check? 0(c) =0. Certainly it checks. What value should we give c? Why not 1? 0/0=1 since 0(1) = 0. But 52 would work equally well. 0/0 = 52 since 0(52) = 0. Since any number will check, 0/0 lacks a "unique" answer. Again mathematicians ruled out 0/0 as a permissible operation because of this lack of uniqueness.
There are some weird number systems where division by the zero of the system is permissible. Those systems have some rather strange properties that renders them nearly useless in solving problems in the real world which is the primary purpose of mathematics.
