A=(\(\dfrac{\sqrt{x}}{\sqrt{x}+2}\)-\(\dfrac{x+4}{x-4}\)):(\(\dfrac{2\sqrt{x}}{x-2\sqrt{x}}\)-\(\dfrac{1}{\sqrt{x}}\))
=(\(\dfrac{\sqrt{x}}{\sqrt{x}+2}\)-\(\dfrac{x-4}{\left(\sqrt{x}-2\right)\cdot\left(\sqrt{x}+2\right)}\)):(\(\dfrac{2\sqrt{x}-1}{\sqrt{x}\cdot\left(\sqrt{x}-2\right)}\)-\(\dfrac{1}{\sqrt{x}}\))
=\(\dfrac{\sqrt{x}\cdot\left(\sqrt{x}-2\right)-\left(x+4\right)}{\left(\sqrt{x}+2\right)\cdot\left(\sqrt{x}-2\right)}\):\(\dfrac{\left(2\cdot\sqrt{x}-1\right)-\left(\sqrt{x}-2\right)}{\sqrt{x}\cdot\left(\sqrt{x}-2\right)}\)
=\(\dfrac{x-2\cdot\sqrt{x}-x-4}{\left(\sqrt{x}+2\right)\cdot\left(\sqrt{x}-2\right)}\)\(\cdot\)\(\dfrac{\sqrt{x}\cdot\left(\sqrt{x}-2\right)}{2\cdot\sqrt{x}-1-\sqrt{x}+2}\)
=\(\dfrac{-2\cdot\sqrt{x}-4}{\left(\sqrt{x}-2\right)\cdot\left(\sqrt{x}+2\right)}\)\(\cdot\)\(\dfrac{\sqrt{x}\cdot\left(\sqrt{x}-2\right)}{\sqrt{x}+1}\)
=\(\dfrac{-2\left(\sqrt{x}+2\right)}{\left(\sqrt{x}+2\right)\left(\sqrt{x}-2\right)}\)\(\cdot\)\(\dfrac{\sqrt{x}\left(\sqrt{x}-2\right)}{\sqrt{x}+1}\)
=\(\dfrac{-2\sqrt{x}}{\sqrt{x}+1}\)
