Lời giải:
PT $\Leftrightarrow (2x^2+1)^2-(4x+12)^2+11(2x^2+4x+13)=0$
$\Leftrightarrow (2x^2+1-4x-12)(2x^2+1+4x+12)+11(2x^2+4x+13)=0$
$\Leftrightarrow (2x^2-4x-11)(2x^2+4x+13)+11(2x^2+4x+13)=0$
$\Leftrightarrow (2x^2+4x+13)(2x^2-4x)=0$
\(\Rightarrow \left[\begin{matrix} 2x^2+4x+13=0\\ 2x^2-4x=0\end{matrix}\right.\)
Nếu $2x^2+4x+13=0\Leftrightarrow 2(x+1)^2=-11< 0$ (vô lý)
Nếu $2x^2-4x=0\Leftrightarrow 2x(x-2)=0\Rightarrow x=0$ hoặc $x=2$
\(\left(2x^2+1\right)^2-16\left(x+3\right)^2+11\left(2x^2+4x+13\right)=0\)
...
\(4x^4+10x^2-52x=0\)
\(2x\left(2x^3+5x-26\right)=0\)
\(2x\left(2x^2+4x+13\right)\left(x-2\right)=0\)
\(\left[{}\begin{matrix}x=0\\x=2\end{matrix}\right.\)
Tự tính tiếp vs : \(2x^2+4x+13=0\)
