add or subtract the given expressions, simplifying each result and note the combined excluded values.

   1. ((x-2) / (x+2))+(1 / (x2 -4))-((x+2) / (2-x))=(2x^2+9)/(x^2-4)

   2. ((x-3) / (x+3))-(1 / (x-3))+((x+2) / (3-x))=-(12x)/(x^2-9)

\(1.\\ \frac{(x-2) }{ (x+2)}+\frac{1 }{ (x^2 -4)}-\frac{(x+2) }{ (2-x)}\\ =\frac{(x-2)(x-2) }{ (x+2)(x-2)}+\frac{1 }{ (x-2)(x+2)}-\frac{(x+2)(x+2) }{ (2-x)(x+2)}\\ =\frac{(x-2)(x-2)\;\;+1\;\;-[ (x+2)(x+2)]}{ (x+2)(x-2)}\\ =\frac{(x^2-4x+4)\;\;-[ x^2+4x+4]\;\;+1}{ (x+2)(x-2)}\\ =\frac{(x^2-4x+4)\;\;+[- x^2-4x-4]\;\;+1}{ (x+2)(x-2)}\\ =\frac{x^2-4x+4- x^2-4x-4\;\;+1}{ (x+2)(x-2)}\\ =\frac{-8x\;\;+1}{ (x+2)(x-2)}\\ =\frac{1-8x}{ x^2-4}\\ =\frac{8x-1}{4- x^2}\\\)

You can try the second one yourself. :)