Ta có: \(\dfrac{1}{\left(x-2\right)^2}-\dfrac{1}{x+2}-\dfrac{1}{4-x^2}\)
\(=\dfrac{x+2-\left(x-2\right)^2+x-2}{\left(x-2\right)^2\cdot\left(x+2\right)}\)
\(=\dfrac{2x-x^2+4x-4}{\left(x-2\right)^2\cdot\left(x+2\right)}\)
\(=\dfrac{-x^2+6x-4}{\left(x-2\right)^2\cdot\left(x+2\right)}\)