Cho hàm số f (x) Đồ thị hàm số ...

C

- Hướng dẫn giải

Ta có:

\(\begin{array}{l}
f'\left( x \right) > 0 \Leftrightarrow \left[ {\begin{array}{*{20}{c}}
{ - 2 < x < 2}\\
{x > 5\,\,\,\,\,\,\,\,\,\,\,\,}
\end{array}} \right.\\
g'\left( x \right) = \left[ {f\left( {3 - 2x} \right)} \right]' =  - 2f'\left( {3 - 2x} \right)\\
 =  > g'\left( x \right) < 0 \Leftrightarrow f'\left( {3 - 2x} \right) > 0\\
 \Leftrightarrow \left[ {\begin{array}{*{20}{c}}
{ - 2 < 3 - 2x < 2}\\
{3 - 2x > 5\,\,\,\,\,\,\,}
\end{array}} \right. \Leftrightarrow \left[ {\begin{array}{*{20}{c}}
{\frac{1}{2} < x < \frac{5}{2}}\\
{x <  - 1\,\,\,\,}
\end{array}} \right.
\end{array}\)