\(x^3-6x^2+5x=0\Leftrightarrow x\left(x^2-6x+5\right)=0\)
\(\Leftrightarrow x\left(x^2-x-5x+5\right)=0\)
\(\Leftrightarrow x\left[x\left(x-1\right)-5\left(x-1\right)\right]=0\Leftrightarrow x\left(x-1\right)\left(x-5\right)=0\Leftrightarrow x=0;x=1;x=5\)
\(x^3-6x^2+5x=0\)
\(\Leftrightarrow x.\left(x^2-6x+5\right)=0\)
\(\Leftrightarrow x.\left(x^2-x-5x+5\right)=0\)
\(\Leftrightarrow x.\left[\left(x^2-x\right)-\left(5x-5\right)\right]=0\)
\(\Leftrightarrow x.\left[x\left(x-1\right)-5\left(x-1\right)\right]=0\)
\(\Leftrightarrow x\left(x-1\right)\left(x-5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}x=0\\x-1=0\\x-5=0\end{matrix}\right.\) \(\Leftrightarrow\left[{}\begin{matrix}x=0\\x=1\\x=5\end{matrix}\right.\)
Vậy \(x\in\left\{0;1;5\right\}\)
