Đáp án+Giải thích các bước giải:
`3 . (x - 1)^2 - 2x . (x - 1) = 0`
`=> 3 . (x - 1) . (x - 1) - 2x^2 + 2x = 0`
`=> 3 . (x^2 - 2x + 1) - 2x^2 + 2x = 0`
`=> 3x^2 - 6x + 3 - 2x^2 + 2x = 0`
`=> (3x^2 - 2x^2) - (6x - 2x) + 3 = 0`
`=> x^2 - 4x + 3 = 0`
`=> x^2 - x - 3x + 3 = 0`
`=> (x^2 - x) - (3x - 3) = 0`
`=> x . (x - 1) - 3 . (x - 1) = 0`
`=> (x - 3) . (x - 1) = 0`
`=>` $\left[\begin{matrix} x-3=0\\ x-1=0\end{matrix}\right.$
`=>`$\left[\begin{matrix} x=0+3\\ x=0+1\end{matrix}\right.$
`=>`$\left[\begin{matrix} x=3\\ x=1\end{matrix}\right.$
Vậy `x in {3;1}`
`x(x-1)=0`
`=>`$\left[\begin{matrix} x=0\\ x-1=0\end{matrix}\right.$
`=>`$\left[\begin{matrix} x=0\\ x=0+1\end{matrix}\right.$
`=>`$\left[\begin{matrix} x=0\\ x=1\end{matrix}\right.$
Vậy `x in {0;1}`
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Áp dụng:
`a.b=0`
`=>`$\left[\begin{matrix} a=0\\ b=0\end{matrix}\right.$
