TXĐ: \(D=R\)
\(f'\left(x\right)=4x^3-24x\)
\(f'\left(x\right)=0\Rightarrow\left[{}\begin{matrix}x=0\\x=\sqrt{6}\\x=-\sqrt{6}\left(loai\right)\end{matrix}\right.\)
\(\begin{matrix}f\left(0\right)=-1\\f\left(\sqrt{6}\right)=-37\\f\left(9\right)=5588\end{matrix}\)
suy ra chọn D