Question

[Ichigo Hollow]

ycbt\(\Leftrightarrow\left\{{}\begin{matrix}a< 0\\\Delta^{phay}\le0\end{matrix}\right.hay\left\{{}\begin{matrix}-1< 0\\a^2-\left[\left(-1\right)\left(-a+2a-6\right)\right]\le0\end{matrix}\right.\)

\(\Leftrightarrow a^2+a-6\le0\Leftrightarrow-3\le a\le2\)\(\Rightarrow a\in\left[-3;2\right]\)