\(\left(x-5\right)^4=\left(x-5\right)\)
\(\Leftrightarrow\left(x-5\right)^4-\left(x-5\right)=0\)
\(\Leftrightarrow\left[\left(x-5\right)^3-1\right]\left(x-5\right)=0\)
\(\Leftrightarrow\left[{}\begin{matrix}\left(x-5\right)^3-1=0\\x-5=0\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}\left(x-5\right)^3=1\\x=5\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x-5=1\\x=5\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}x=6\\x=5\end{matrix}\right.\)
Vậy =
