Giới hạn lim x → + ∞ √ x 2 + 2 − 2 x − 2 bằng

B

\(\mathop {\lim }\limits_{x \to  + \infty } \frac{{\sqrt {{x^2} + 2}  - 2}}{{x - 2}}\)\( = \mathop {\lim }\limits_{x \to  + \infty } \frac{{x\sqrt {1 + \frac{2}{{{x^2}}}}  - 2}}{{x - 2}}\)\( = \mathop {\lim }\limits_{x \to  + \infty } \frac{{\sqrt {1 + \frac{2}{{{x^2}}}}  - \frac{2}{x}}}{{1 - \frac{2}{x}}} = 1\).