\[\left\{ \begin{matrix} 3x - 4 < 0\ \ \ \ \ \ \ \ \\ \frac{15}{25x^{2} - 36} < 0 \\ \end{matrix} \right.\ \text{\ \ \ \ \ \ \ }\]
\[\left\{ \begin{matrix} x < 1\frac{1}{3}\text{\ \ \ \ \ \ \ \ \ \ \ \ \ \ } \\ 25x^{2} - 36 < 0 \\ \end{matrix} \right.\ \text{\ \ \ \ \ \ \ }\]
\[\left\{ \begin{matrix} x < 1\frac{1}{3}\text{\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ } \\ (5x - 6)(5x + 6) < 0 \\ \end{matrix}\ \right.\ \]
\[\left\{ \begin{matrix} x < 1\frac{1}{3}\text{\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ } \\ 25 \cdot (x - 1,2)(x + 1,2) < 0 \\ \end{matrix} \right.\ \]
\[Ответ:( - 1,2;1,2).\]