\(x^2-2x=0\)

\(\Rightarrow x\left(x-2\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x-2=0\Rightarrow x=2\end{matrix}\right.\)

\(x^3+3x=0\)

\(\Rightarrow x\left(x^2+3\right)=0\)

\(\Rightarrow\left[{}\begin{matrix}x=0\\x^2+3=0\Rightarrow x^2=-3\Rightarrow x=-\sqrt{3}\end{matrix}\right.\)

ko hiểu đề cho lắm