Đáp án:
$\begin{array}{l}
\mathop {\lim }\limits_{x \to - 1} \frac{{{x^2} - x - 2}}{{{x^3} + {x^2} + x + 1}}\\
= \mathop {\lim }\limits_{x \to - 1} \frac{{\left( {x + 1} \right)\left( {x - 2} \right)}}{{\left( {x + 1} \right)\left( {{x^2} + 1} \right)}}\\
= \mathop {\lim }\limits_{x \to - 1} \frac{{x - 2}}{{{x^2} + 1}}\\
= \frac{{ - 1 - 2}}{{1 + 1}} = - \frac{3}{2}
\end{array}$
