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# Lewis Carroll's puzzler

3 replies to this topic

### #1 RyanM

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Posted 22 November 2007 - 05:31 AM

This puzzle was created by Lewis Carroll, the author of "Alice's Adventures in Wonderland" and "Through the Looking Glass". Besides authoring two classic children's books, he was an accomplished mathematician.

Assume that x=0.

therefore, 3x=4x.

divide by x on both sides. you will find...

that 3=4! How is this?

Good luck!
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### #2 carlosn27

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Posted 22 November 2007 - 07:11 AM

any number divided by zero is an undefined number.
that's how.
hence, this is not possible.
3x can equal 4x, but 3x/x does not equal 4x/x, because those would both be undefined numbers.

on top being an author, mathematician, logician, inventor, photographer, and a clergyman; wasnt Dodgson also an alleged pedophile?
http://findarticles....26/ai_n16816379
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### #3 timforyou12

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Posted 07 December 2007 - 04:39 PM

Oh, I think I get it.
3x=4x
subtract 3x from both sides and you get:
0=x
However, that would not explain how you get 3=4.
If you were to plug 0 in for x you would get:
0=0
Divide by x on both sides and you get
0/0=0/0
Since dividing by 0 results in an impossible number, you wouldn't be able to reach any further steps
I learned complex and imaginary numbers a few weeks ago in Algebra 2 and if I remember correctly, dividing by 0 produces neither of these.
My friend studies calculus a lot in his spare time (we're both only High School Freshmen ) and he was trying to explain to me what happens when you divide by 0...
I didn't really get it because he used integrals and stuff.
But still... I don't think this would work
Anyway, I'm sure that I'm overthinking this and that there's a much simpler solution, but I can't find it so there!

To quote my Algebra Teacher
"Dividing by 0 would be like saying you had 0 of "x" and
then you used "x" amount of something, for example:
I have ) pieces of pie and I eat 4 of them because apparently
I can conjure up matter out of nothingness!"

Thus, to divide by 0, you would either be god, or Chuck Norris
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### #4 timforyou12

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Posted 07 December 2007 - 04:59 PM

oops! in last post, my quote said ) instead of 0
I apologize
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