\(\left(x^2-4\right)^2-3^2-\left(8x-8\right)=0\)
\(\Leftrightarrow\left(x^2-1\right)\left(x^2-7\right)-8\left(x-1\right)=0\)
\(\Leftrightarrow\left(x-1\right)\left(x+1\right)\left(x^2-7\right)-8\left(x-1\right)=0\)
\(\Leftrightarrow\left(x-1\right)\left[\left(x+1\right)\left(x^2-7\right)-8\right]=0\)
\(\Leftrightarrow\left(x-1\right)\left[\left(x+1\right)\left(x^2-7\right)-4\left(x^2-7\right)+4\left(x^2-7\right)-8\right]=0\)
\(\Leftrightarrow\left(x-1\right)\left[\left(x-3\right)\left(x^2-7\right)+4\left(x-3\right)\left(x+3\right)\right]=0\)
\(\Leftrightarrow\left(x-1\right)\left(x-3\right)\left(x^2+4x+5\right)=0\)
\(\Rightarrow\left[{}\begin{matrix}x-1=0\\x-3=0\\x^2+4x+5=0\left(vn\right)\end{matrix}\right.\) \(\Rightarrow\left[{}\begin{matrix}x=1\\x=3\end{matrix}\right.\)
