Đặt \(t=2x^2+3x-1\), pt trở thành:
\(t^2-7\left(t+4\right)+33=0\)
\(\Leftrightarrow t^2-7t+5=0\)
\(\Leftrightarrow\left[{}\begin{matrix}t=\dfrac{7+\sqrt{29}}{2}\\t=\dfrac{7-\sqrt{29}}{2}\end{matrix}\right.\)
\(\Leftrightarrow\left[{}\begin{matrix}2x^2+3x-1=\dfrac{7+\sqrt{29}}{2}\\2x^2+3x-1=\dfrac{7-\sqrt{29}}{2}\end{matrix}\right.\)
Nghiệm xấu xuất sắc =]]