\[x^{3} + 6x^{2} - x - 6 = 0\]
\[x^{2}(x + 6) - (x + 6) = 0\]
\[(x + 6)\left( x^{2} - 1 \right) = 0\]
\[(x + 6)(x - 1)(x + 1) = 0\]
\[x = - 6;\ \ \ x = 1;\ \ \ x = - 1\]
\[Ответ:x = \pm 1;\ \ x = - 6.\]