\[\left( x^{2} - 7x - 6 \right)\left( x^{2} + 11x - 6 \right) = 0\]
\[1)\ x^{2} - 7x - 6 = 0\]
\[D = 49 + 24 = 73\]
\[x = \frac{7 \pm \sqrt{73}}{2}.\]
\[2)\ x^{2} + 11x - 6 = 0\]
\[D = 121 + 24 = 145\]
\[x = \frac{- 11 \pm \sqrt{145}}{2}.\]
\[Ответ:\ \ \frac{7 \pm \sqrt{73}}{2};\ \frac{- 11 \pm \sqrt{145}}{2}.\]
\[Подставим:\]
\[x^{2} - 6x + 6 \pm \sqrt{37}x = 0\]
\[x^{2} - \left( 6 \pm \sqrt{37} \right)x + 6 = 0\]
\[D = \left( 6 \pm \sqrt{37} \right)^{2} - 4 \bullet 6 =\]
\[= 36 \pm 12\sqrt{37} + 37 - 24 =\]
\[= 49 \pm 12\sqrt{37} = 49 + 12\sqrt{37}\]
\[x = \frac{6 + \sqrt{37} \pm \sqrt{49 + 12\sqrt{37}}}{2}.\]
\[Ответ:\ \ \frac{6 + \sqrt{37} \pm \sqrt{49 + 12\sqrt{37}}}{2}.\]