\(\frac{x^2-5x+4}{x^2-2}=5\left(x-1\right)\)
\(\Rightarrow\frac{x^2-x-4x+4}{x^2-2}=5\left(x-1\right)\)
\(\Rightarrow\frac{x\left(x-1\right)-4\left(x-1\right)}{x^2-2}=5\left(x-1\right)\)
\(\Rightarrow\frac{\left(x-1\right)\left(x-4\right)}{x^2-2}=5\left(x-1\right)\)
Với x = 1
=> x - 1 = 0
=> \(\frac{0.\left(x-4\right)}{x^2-2}=5.0\)
=> 0 = 0 ( luôn đúng )
Với x khác 1
=> x - 1 khác 0
=> \(\frac{x-4}{x^2-2}=5\)( chia cả hai vế cho x - 1 )
=> \(x-4=5x^2-10\)
=> \(5x^2-x-6=0\)
=> \(5x^2+5x-6x-6=0\)
=> \(5x\left(x+1\right)-6\left(x+1\right)=0\)
=> \(\left(x+1\right)\left(5x-6\right)=0\)
=> \(\orbr{\begin{cases}x+1=0\\5x-6=0\end{cases}\Rightarrow\orbr{\begin{cases}x=-1\\x=\frac{6}{5}\end{cases}}}\)
Vậy \(x\in\left\{1;-1;\frac{6}{5}\right\}\)