a) \(\left(\dfrac{4x}{2+x}+\dfrac{8x^2}{4-x^2}\right):\left(\dfrac{x-3}{x^2-2x}-\dfrac{2}{x}\right)\)
\(\left[\dfrac{4x}{2+x}+\dfrac{8x^2}{\left(2+x\right)\left(2-x\right)}\right]:\left[\dfrac{x-3}{x\left(x-2\right)}-\dfrac{2}{x}\right]\)
\(\left[\dfrac{4x\left(2-x\right)}{4-x^2}+\dfrac{8x^2}{4-x^2}\right]:\left[\dfrac{x-3}{x\left(x-2\right)}-\dfrac{2\left(x-2\right)}{x\left(x-2\right)}\right]\)
\(\dfrac{8x-4x^2+8x^2}{\left(2+x\right)\left(2-x\right)}:\dfrac{x-3-2x+4}{x\left(x-2\right)}\)
\(\dfrac{8x+4x^2}{\left(2+x\right)\left(2-x\right)}\cdot\dfrac{x\left(x-2\right)}{1-x}\)
\(\dfrac{4x\left(2+x\right)}{\left(2+x\right)\left(2-x\right)}\cdot\dfrac{x\left(x-2\right)}{1-x}\)
\(\dfrac{-4x}{x-2}\cdot\dfrac{x\left(x-2\right)}{1-x}\)
\(\dfrac{-4x^2}{1-x}\)