Đáp án:
\(\begin{array}{l}
+ )\,\,\,\left( * \right)\,\,\,co\,\,\,1\,\,\,\,nghiem \Leftrightarrow \left[ \begin{array}{l}
m > 3\\
m < - 1
\end{array} \right.\\
+ )\,\,\,\left( * \right)\,\,\,co\,\,\,2\,\,nghiem \Leftrightarrow \left[ \begin{array}{l}
m = - 1\\
m = 3
\end{array} \right.\\
+ )\,\,\,\left( * \right)\,\,\,co\,\,\,3\,\,\,nghiem \Leftrightarrow - 1 < m < 3.
\end{array}\)
Giải thích các bước giải:
