3x(x-2)=6(22-x) x^3-4x=0

Đáp án `+` Giải thích các bước giải:

`3x(x-2)=6(22-x)`

`=>3x(x-2)-6(22-x)=0`

`=>3x^2 -6x-132-6x=0`

`=>3x^2 -132-6x-6x=0`

`=>3x^2 -132-0=0`

`=>3x^2 -3.44=0`

`=>3(x^2 -44)=0`

`=>x^2 -44=0`

`=>x^2 =44`

`=>`$\left[\begin{matrix} x=\sqrt{44}\\ x=-\sqrt{44}\end{matrix}\right.$

Vậy `x=+-\sqrt{44}`

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`x^3 -4x=0`

`=>x.x^2 -4x=0`

`=>x(x^2 -4)=0`

`=>x(x-2)(x+2)=0`

`=>`$\left[\begin{matrix} x=0\\ x-2=0\\ x+2=0\end{matrix}\right.$

`=>`$\left[\begin{matrix} x=0\\ x=2\\ x=-2\end{matrix}\right.$

Vậy `x\in{0;+-2}`