Bài tập 29 trang 159 SGK Toán 11 NC

Ta có:

\(\begin{array}{*{20}{l}}
\begin{array}{l}
\mathop {\lim }\limits_{x \to {{\left( { - 2} \right)}^ - }} f\left( x \right) = \mathop {\lim }\limits_{x \to {{\left( { - 2} \right)}^ - }} \left( {2\left| x \right| - 1} \right)\\
 = 2.\left| { - 2} \right| - 1 = 3
\end{array}\\
{\mathop {\lim }\limits_{x \to {{\left( { - 2} \right)}^ + }} f\left( x \right) = \mathop {\lim }\limits_{x \to {{\left( { - 2} \right)}^ + }} \sqrt {2{x^2} + 1}  = 3}\\
{ \Rightarrow \mathop {\lim }\limits_{x \to  - 2} f\left( x \right) = 3}
\end{array}\)

-- Mod Toán 11 HỌC247