Cho các giới hạn Lim f(x) = 2

19/39

Cho các giới hạn \(\mathop {\lim }\limits_{x \to {x_0}} f\left( x \right) = 2\); \(\mathop {\lim }\limits_{x \to {x_0}} g\left( x \right) = 3\). Tính \(\mathop {\lim }\limits_{x \to {x_0}} \left[ {3f\left( x \right) - 4g\left( x \right)} \right]\).

\(5\).

\(2\).

\( - 6\).

\(3\).

Giải thích

Đáp án đúng là: C

Có \(\mathop {\lim }\limits_{x \to {x_0}} \left[ {3f\left( x \right) - 4g\left( x \right)} \right]\)

\( = \mathop {\lim }\limits_{x \to {x_0}} 3f\left( x \right) - \mathop {\lim }\limits_{x \to {x_0}} 4g\left( x \right)\)

\( = 3\mathop {\lim }\limits_{x \to {x_0}} f\left( x \right) - 4\mathop {\lim }\limits_{x \to {x_0}} g\left( x \right)\)

\( = 3 \cdot 2 - 4 \cdot 3 = - 6\).