`@`\(\dfrac{\sqrt{x^2-2x+1}}{x-1}=\dfrac{\sqrt{\left(x-1\right)^2}}{x-1}=\dfrac{\left|x-1\right|}{x-1}=\dfrac{x-1}{x-1}=1\)
`@`\(\left(x-2\right)+\dfrac{\sqrt{x^2-4x+4}}{x-2}=\left(x-2\right)+\dfrac{\sqrt{\left(x-2\right)^2}}{x-2}=\left(x-2\right)+\dfrac{\left|x-2\right|}{x-2}=x-2+\dfrac{2-x}{x-2}=x-2-\dfrac{x-2}{x-2}=x-2-1=x-3\)
`+)x>1`
`<=>x-1>0`
`(\sqrt{x^2 -2x+1})/(x-1)`
`=(\sqrt{(x-1)^2})/(x-1)`
`=(|x-1|)/(x-1)~`
`=(x-1)/(x-1)`
`=1`
Vậy...
`+)x<2`
`<=>x-2<0`
`|x-2|+(\sqrt{x^2-4x+4})/(x-2)`
`=2-x+(\sqrt{(x-2)^2})/(x-2)`
`=2-x+(|x-2|)/(x-2)`
`=2-x+(2-x)/(-(2-x))`
`=2-x-1`
`=1-x`
Vậy...