`#tnvt`
`A=[1-\frac{x+\sqrt{x}}{\sqrt{x}+1}].[1-\frac{x-\sqrt{x}}{\sqrt{x}-1}]`
`a,`
`ĐK:{(x>=0),(\sqrt{x}-1\ne0):}<=>{(x>=0),(\sqrt{x}\ne1):}`
`<=>{(x>=0),(x\ne1):}`
Vậy `ĐKXĐ: x>=0,x\ne1`
`A=[1-\frac{x+\sqrt{x}}{\sqrt{x}+1}].[1-\frac{x-\sqrt{x}}{\sqrt{x}-1}](x>=0,x\ne1)`
`=[1-\frac{\sqrt{x}(\sqrt{x}+1)}{\sqrt{x}+1}].[1-\frac{\sqrt{x}(\sqrt{x}-1)}{\sqrt{x}-1}]`
`=[1-\sqrt{x}].[1-\sqrt{x}]`
`=(1-\sqrt{x})^2`
`=(\sqrt{x}-1)^2`
`∀x>=0`
`=>\sqrt{x}-1>=-1`
`=>(\sqrt{x}-1)^2>=1`
Dấu `=` xảy ra khi `\sqrt{x}-1=-1<=>x=0(tm)`
Vậy `GTNNNN_M=1` khi `x=0`