Main      Site Guide    
Message Forum
Division by zero error
Posted By: Nyperold, on host 205.216.76.250
Date: Friday, November 26, 1999, at 09:40:56
In Reply To: Re: 2=1. Cool! posted by Wolfspirit on Friday, November 26, 1999, at 05:22:18:

> > Well, I tried to remember it. I think there was more, but here is the informal proof for 2=1.
> >
> > Given: a=1; b=1
> > Thus, a=b [reference number 1]
> >
> > b^2 - a^2 = b^2 - a^2 [reflexive property]
> > b^2 - a^2 = b^2 - aa [def. square]
> > b^2 - a^2 = b^2 - bb [ref. #1]
> > (b-a)(b+a) = b(b-a) [undistributing]
> > b+a = b [subtract like term from both sides of equation]
> > 1+1 = 1 [a=1; b=1]
> > 2 = 1
> >
> > Chr"makes up her own proof format and geometric terms"is
>
> Ah. Cool. This is the first proof I've seen for why "Division by zero" is an illegal operation in mathematics. You know how that's one of the first rules you learn in elementary school, but never knew why it's so? Well now you *know*, because of stuff like this. Isn't it exciting? :-)
>
>
> > Yay! My brother came back! He's supposed to be in Fairbanks!
> > Ugh... never thought I'd be glad to see him.
> > Happy Thanksgiving, all.
>
> Likewise, a Happy Thanksgiving; may grace and peace go with you all, in family and friendship.
>
> Wolfspirit

You can also think of the simple(yet tedious) way of dividing a by b. You subtract b from a until a is less than b, and keep track of the number of subtractions. Since subtracting 0 from a number doesn't do anything to it, a/0=infinity. Not many(read: No) computers are equipped to handle numbers that large, and you can't really do anything with that number anyway.

Nyperold