\(2x^2-x-7+2\sqrt{6x+11}=0\)
☘ Điều kiện: \(x\ge-\dfrac{11}{6}\)
\(\Leftrightarrow2\sqrt{6x+11}=-2x^2+x+7\)
\(\Leftrightarrow\left\{{}\begin{matrix}-2x^2+x+7\ge0\\24x+44=4x^4+x^2+49-4x^3-28x^2+14x\end{matrix}\right.\)
\(\Leftrightarrow\left\{{}\begin{matrix}\dfrac{1-\sqrt{57}}{4}\le x\le\dfrac{1+\sqrt{57}}{4}\\4x^4-4x^3-27x^2-10x+5=0\left(1\right)\end{matrix}\right.\)
\(\Leftrightarrow\left(2x^2-5x-5\right)\left(2x^2+3x-1\right)=0\)
⚠ Tự giải tiếp nha.