Đáp án+Giải thích các bước giải:
`(\frac{\sqrt{x}}{\sqrt{x}+2}-\frac{\sqrt{x}}{\sqrt{x}-2}+\frac{4\sqrt{x}-1}{x-4}):\frac{1}{x-4}(x\ne4,x>=0)`
`=(\frac{\sqrt{x}(\sqrt{x}-2)-\sqrt{x}(\sqrt{x}+2)+4\sqrt{x}-1}{x-4}).\frac{x-4}{1}`
`=\frac{x-2\sqrt{x}-x-2\sqrt{x}+4\sqrt{x}-1}{x-4}.\frac{x-4}{1}`
`=\frac{(x-x)+(-2\sqrt{x}-2\sqrt{x}+4\sqrt{x})-1}{x-4}.\frac{x-4}{1}`
`=\frac{-1}{1}`
`=-1`
`=>(\frac{\sqrt{x}}{\sqrt{x}+2}-\frac{\sqrt{x}}{\sqrt{x}-2}+\frac{4\sqrt{x}-1}{x-4}):\frac{1}{x-4}=-1`
`=>đpcm`
