proof that 1=2 Code (Text): (1) X=Y ; Given (2) X^2=XY ; Multiply both sides by X (3) X^2-Y^2=XY-Y^2 ; Subtract Y^2 from both sides (4) (X+Y)(X-Y)=Y(X-Y) ; Factor (5) X+Y=Y ; Cancel out (X-Y) term (6) 2Y=Y ; Substitute X for Y, by equation 1 (7) 2=1 ; Divide both sides by Y ahaha...too bad that is so not a legit proof
Code (Text): (1) X=Y ; Given (2) X^2=XY ; Multiply both sides by X (3) X^2-Y^2=XY-Y^2 ; Subtract Y^2 from both sides (4) (X+Y)(X-Y)=Y(X-Y) ; Factor (5) X+Y=Y ; Cancel out (X-Y) term (6) 2Y=Y ; Substitute X for Y, by equation 1 (7) OH=SHI- ; Divide both sides by 0 Fix'd.
I sure can't... someone willing to explain ? I can't believe that I ended up with a 100% result in my final exam but can't even see what's wrong in this [...]
Spoiler (pretty sure this is it) Basically X-Y = 0, from step 1. After step 4 you "cancel" out the term, by dividing X-Y from both sides. Like Virre said, you're dividing using 0, which is undefined. Jump to step 7
Yes to commy. I think it's ironic that dividing by zero results in 2 equaling 1...yet another doomsday thing resulting from dividing by zero.
I wonder who invented all these silly algebraic rules anyway. They just don't make sense! Very clever thread xD
Haha, I remember when I first saw this I spent like 30 minutes trying to figure it out. Anyone seen that one with women? I'm not sexist or anything, but it was pretty funny.
haha nice http://www.math.utah.edu/~cherk/mathjokes.html my favorite site for math jokes...especially the definitions part (which can also be used as a test of how nerdy you are)
aww <3 math jokes though I must say...they get really repetitive (like the chemist/physicists/mathematician ones) here's where I got that 1=2 proof: http://motd.ambians.com/quotes.php/name ... _id/1-1-30