bladerider

x - y = 0
2x - 2y = 0
x - y = 2x - 2y
1(x - y) = 2(x - y)
1 = 2

if x minus y equals zero
that means 2 times x minus 2 times y also equals zero right?
so that would mean x minus y equals 2 times x minus 2 times y
if you cross divide both sides of the equation by x minus y
your left with 1 equals two.







worked out the flaw yet.












both x and y are the number 0. Any number multiplied by zero will always equal zero.

Luke

So what???

dnb

Being pedantic here, but X and Y both do not have to be 0.
The condition is in fact X=Y.

jjones

doh.

[Edited by jjones - 9/9/2002 11:30:50 PM]

jjones

double doh


[Edited by jjones - 9/9/2002 11:31:12 PM]

jjones

is this the muppet forum?

Ralf

That's wrong of course

x - y = 0
2x - 2y = 0
x - y = 2x - 2y
1(x - y) = 2(x - y)
1 = 2

if
x - y = 0 / +y >
x = y

then of course is
2x - 2y =0 / +2y >
2x = 2y / :2 >
x = y

but now
x - y = 2x - 2y / -x; +2y >
x - x -y + 2y = 2x - x - 2y + 2y
y = x

here comes something undefined:
1(x - y) = 2(x - y) which is 1 * 0 = 2 * 0 which is undefined IIRC

so the next step of
1 = 2
is not correct

shid

Math day today?


Ralf

Jay m A

iTrader: (2)

I thought x went along and y went up

POC

no, it works like this, tis quite straight forward actualy

x - y = 2x - 2y / -x; +2y >
x - x -y + 2y = 2x - x - 2y + 2y
y + x - 2x = x

then if
x - y = 0
x - 2y = 0
x - y = 2x - 2y
1(x - y) = 2(x - y)

then surley
2x - 2y =0 / +2y >
2x = 2y / +2 >
x + 2y - x= y

so you get
x - y = 2x - 2y / -x; +2y
x - y = 0 / +y
x - y = 2x - 2y
x - x -y + 2y = 2x - x - 2y + 2y
y = x

Simple when you really think about it.

P

David_Wallis

you'd expect paul to be good at maths (has to count a lot of cash when buying and selling his cars.)

David

Makalu

y?

carl

1*0 and 2*0 are not undefined, they're 0

The problem arises that you divide both sides by (x-y) which is zero. It's the dividing by zero that's undefined.

Of course if you got to the point where you had 2(x-y)=(x-y) you should pretty rapidly conclude that x=y anyway

Jolly Green Monster 2

but dividing by zero causes and contraint_error


JGM

carl

Only if your compiler can't spell

Jolly Green Monster 2

ROTFL!!! doh...



lucky I didn't write the error messages part..

JGM