OK I am able to see how the textbook arrived at it's answer.
I looked at it and initially thought to factorise because I saw the difference of two squares (x^-2 - y^-2).
But the textbook writer thought to remove the negative exponents first. Strange that both answers look so different but mean...
Homework Statement
Simplify (x-2 - y-2) / (x-1 + y-1)
Homework Equations
The Attempt at a Solution
So I just factorised the numerator into x-1 - y-1 and x-1 + y-1. And was left with x-1 - y-1 as an answer. The textbook gives (y - x) / (xy) as the answer (no working shown). So...