<s>[INST] How to simplify this expression? $\frac{x+1}{x^2+x-2}-\frac x{x^2-1}$. $$\frac{x+1}{x^2+x-2}-\dfrac x{x^2-1}=\text{ ?}$$
This expression needs to be simplified. I've tried to do it but i couldn't.
 [/INST] Hint;
$x^2+x-2=(x-1)(x+2)\tag{1}$
$x^2-1=x^2-1^2=(x-1)(x+1)\tag{2}$
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