Cho Lim {x^2} + 3x - 2) = a

7/32

Cho \[\mathop {\lim }\limits_{x \to 2} ({x^2} + 3x - 2) = a,\mathop {\,\,\,\lim }\limits_{x \to 1} \frac{{4 - 2x}}{{3x - 2}} = b.\]Tính\[a + b\].

\[ + \infty \].

\[10\].

\[6\].

\[8\].

Giải thích

Chọn B

Ta có

\[\left\{ \begin{array}{l}\mathop {\lim }\limits_{x \to 2} ({x^2} + 3x - 2) = 8\\\mathop {\,\,\,\lim }\limits_{x \to 1} \frac{{4 - 2x}}{{3x - 2}} = 2\end{array} \right. \Rightarrow \left\{ \begin{array}{l}a = 8\\b = 2\end{array} \right. \Rightarrow a + b = 10\]