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khalid_kacst
Oct12-03, 03:23 AM
if y not equal x .

what is y and x when

x^2 - y^2 = x - y

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renedox
Oct12-03, 06:05 AM
Only solution I can think of is when x and y is equal to one.
You get:

x = 1; y = 1;

(1)^2 - (1)^2 = (1) - (1)
==> 0 = 0

MathematicalPhysicist
Oct12-03, 08:11 AM
Originally posted by renedox
Only solution I can think of is when x and y is equal to one.
You get:

x = 1; y = 1;

(1)^2 - (1)^2 = (1) - (1)
==> 0 = 0
he asked for solution in which x doesnt equal y.

now i know it's simple but the question seems to be simple
x^2-y^2=x-y
(x-y)*(x+y)=x-y /x-y
x+y=1
now for positive integers it could only be x=0 y=1 or the opposite, the other solutions are negative integers and positive ones.

btw, can someone explain how is this a question about calculus?

mathman
Oct12-03, 06:34 PM
Unless there is a further restriction on x and y (the original question didn't include any), then x+y=1, for any x, will do.

renedox
Oct13-03, 05:37 AM
Originally posted by loop quantum gravity
he asked for solution in which x doesnt equal y.

Gah, don't be tired and browes PF at the same time :P

IceZero
Oct21-03, 11:48 PM
use implicit differentiation and find the derivative

mathman
Oct22-03, 12:01 AM
use implicit differentiation and find the derivative
What has this got to do with it???????

Zargawee
Oct27-03, 12:50 PM
I also wonder the same , and how is that will be useful ?