\(\Leftrightarrow8\left(x^2+\frac{1}{x^2}+2\right)+4\left(x^2+\frac{1}{x^2}\right)^2-4\left(x^2+\frac{1}{x^2}\right)\left(x^2+\frac{1}{x^2}+2\right)=x^2+8x+16\)
Đặt \(a=x^2+\frac{1}{x^2}\)
PTTT \(8\left(a+2\right)+4a^2-4a\left(a+2\right)=x^2+8x+16\)
\(\Leftrightarrow8a+16+4a^2-4a^2-8a=x^2+8x+16\)
\(\Leftrightarrow x^2+8x=0\)
\(\Leftrightarrow\orbr{\begin{cases}x=0\\x=-8\end{cases}}\)
Đặt x+1/x=a
x^2+1/x^2=b
sau đó làm bình thường