Tính \(\mathop {\lim }\limits_{x \to  - 2} \frac{{{x^2} - 2{\rm{x}} - 8}}{{\sqrt {2{\rm{x}} + 5}  - 1}}.\)

Câu hỏi :

Tính \(\mathop {\lim }\limits_{x \to  - 2} \frac{{{x^2} - 2{\rm{x}} - 8}}{{\sqrt {2{\rm{x}} + 5}  - 1}}.\)