Đáp án:
`(x-1)(x-2)-2(x-1)^2=0`
`<=>` `(x-1)[x-2-2(x-1)]=0`
`<=>` `(x-1)[x-2-(2x-2)]=0`
`<=>` `(x-1)(x-2-2x+2)=0`
`<=>` `(x-1)(-x)=0`
`<=>` \(\left[ \begin{array}{l}x-1=0\\-x=0\end{array} \right.\) `<=>` \(\left[ \begin{array}{l}x=1\\x=0\end{array} \right.\)
Vậy `x\in{1;0}`
