Factorise..x^2-2+1/x^2-y^2

Answer 1

It helps to check your typing before you post.
Did you mean
x^2-2+1/x^2-y^2 , the way you typed it. Then there is nothing to do
or
(x^2-2+1)/(x^2-y^2) ?
or
(x^2-2x+1)/(x^2-y^2) ? , then
(x-1)^2 / ((x+y)(x-y))

Answer 2

heck, I wouldn't even rule out
(x^2-2xy+y^2)/(x^2-y^2) = (x-y)^2 / (x-y)(x+y) = (x-y)/(x+y)