Đáp án:
\(m < - \dfrac{1}{3}\)
Giải thích các bước giải:
\(\begin{array}{l}
y = \sqrt {\dfrac{{5 - 2m}}{{3{x^2} - 2x - m}}} \\
DK:\dfrac{{5 - 2m}}{{3{x^2} - 2x - m}} \ge 0\forall x \in R\\
\to \left\{ \begin{array}{l}
5 - 2m \ge 0\\
3{x^2} - 2x - m > 0
\end{array} \right.\forall x \in R\\
\to \left\{ \begin{array}{l}
m \le \dfrac{5}{2}\\
1 - 3.\left( { - m} \right) < 0
\end{array} \right.\\
\to \left\{ \begin{array}{l}
m \le \dfrac{5}{2}\\
1 + 3m < 0
\end{array} \right.\\
\to \left\{ \begin{array}{l}
m \le \dfrac{5}{2}\\
m < - \dfrac{1}{3}
\end{array} \right.\\
KL:m < - \dfrac{1}{3}
\end{array}\)
