\(\left(n-2\right)^2=\left(n-2\right)^4\)
\(\Rightarrow\left(n-2\right)^2=\left(n-2\right)^2.\left(n-2\right)^2\)
\(\Leftrightarrow\left(n-2\right)^2.\left(n-2\right)^2=\left(n-2\right)^2\)
\(\Rightarrow\left(n-2\right)^2=\left(n-2\right)^2:\left(n-2\right)^2\)
\(\Rightarrow\left(n-2\right)^2=\left(\pm1\right)^2\)
\(\Rightarrow\left[{}\begin{matrix}n-2=1\-2=-1\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}n=3\=1\end{matrix}\right.\)
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