Tính giới hạn lim x → 1 √ 10 − x 2 − 3 1 − x 2 .

B

\(\mathop {\lim }\limits_{x \to 1} \frac{{\sqrt {10 - {x^2}}  - 3}}{{1 - {x^2}}}\)\( = \mathop {\lim }\limits_{x \to 1} \frac{{1 - {x^2}}}{{\left( {1 - {x^2}} \right)\left( {\sqrt {10 - {x^2}}  + 3} \right)}}\)\( = \mathop {\lim }\limits_{x \to 1} \frac{1}{{\sqrt {10 - {x^2}}  + 3}} = \frac{1}{6}\).