`A=\frac{x-10}{x-\sqrt{x}-2}-\frac{\sqrt{x}-1}{\sqrt{x}-2}+\frac{\sqrt{x}-2}{\sqrt{x}+1}(x>=0,x\ne4)`
`=\frac{x-10}{x+\sqrt{x}-2\sqrt{x}-2}-\frac{(\sqrt{x}-1)(\sqrt{x}+1)}{(\sqrt{x}-2)(\sqrt{x}+1)}+\frac{(\sqrt{x}-2)^2}{(\sqrt{x}+1)(\sqrt{x}-2)}`
`=\frac{x-10-x+1+x-4\sqrt{x}+4}{(\sqrt{x}+1)(\sqrt{x}-2)}`
`=\frac{x-4\sqrt{x}-5}{(\sqrt{x}+1)(\sqrt{x}-2)}`
`=\frac{x+\sqrt{x}-5\sqrt{x}-5}{(\sqrt{x}+1)(\sqrt{x}-2)}`
`=\frac{(\sqrt{x}+1)(\sqrt{x}-5)}{(\sqrt{x}+1)(\sqrt{x}-2)}`
`=\frac{\sqrt{x}-5}{\sqrt{x}-2}`