\(8x^3-50x=0\\ x\left(8x^2-50\right)=0\\ \Rightarrow\left[{}\begin{matrix}x=0\\8x^2=50\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=\frac{5}{2}\end{matrix}\right.\)
Vậy \(x\in\left\{0;\frac{5}{2}\right\}\)
\(8x^3-50x=0\)
\(\Rightarrow x.\left(8x^2-50\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\8x^2-50=0\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\8x^2=50\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x^2=50:8\end{matrix}\right.\)
\(\Rightarrow\left[{}\begin{matrix}x=0\\x^2=\frac{25}{4}\end{matrix}\right.\Rightarrow\left[{}\begin{matrix}x=0\\x=\frac{5}{2}\\x=-\frac{5}{2}\end{matrix}\right.\)
Vậy \(x\in\left\{0;\frac{5}{2};-\frac{5}{2}\right\}.\)
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