\(x^3-25x=0\Leftrightarrow x\left(x^2-25\right)=0\) \(\Leftrightarrow\left\{{}\begin{matrix}x=0\\x^2-25=0\end{matrix}\right.\) \(\Leftrightarrow\left\{{}\begin{matrix}x=0\\\left\{{}\begin{matrix}x=5\\x=-5\end{matrix}\right.\end{matrix}\right.\) vậy \(x=0;x=5;x=-5\)
\(x^3-25x=0\\\Leftrightarrow x\left(x^2-25\right)=0\\ \Leftrightarrow x\left(x^2-5^2\right)=0\\ \Leftrightarrow x\left(x+5\right)\left(x-5\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\\x+5=0\\x-5=0\end{matrix}\right.\Leftrightarrow\left[{}\begin{matrix}x=0\\x=-5\\x=5\end{matrix}\right. \)
Vậy \(x=0\) hoặc \(x=-5\) hoặc \(x=5\)
Ta có: \(x^3\)-25x=0
\(\Leftrightarrow\)x(\(x^2-25\))=0
\(\Leftrightarrow\)x(\(x^{2-}\)5\(^2\))=0\(\Leftrightarrow x\left(x-5\right)\left(x+5\right)=0\)
\(\Leftrightarrow\)\(\left\{{}\begin{matrix}x=0\\x-5=0\\x+5=0\end{matrix}\right.\Leftrightarrow\)\(\left\{{}\begin{matrix}x=0\\x=5\\x=-5_{ }\end{matrix}\right.\)
