$9.248 \log _{3}\left(3^{x}-1\right) \log _{1 / 3}\left(3^{x+2}-9\right)>-3$.

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$9.248 \log _{3}\left(3^{x}-1\right) \log _{1 / 3}\left(3^{x+2}-9\right)>-3$.
Solution. $\log _{3}\left(3^{x}-1\right) \cdot \log _{3} 9\left(3^{x}-1\right)<3$. Let $y=\log _{3}\left(3^{x}-1\right)$, then $y(y+2)<3 \Leftrightarrow-3<y<1 \Leftrightarrow \log _{3} \frac{1}{27}<\log _{3}\left(3^{x}-1\right)<\log _{3} 3 \Leftrightarrow$ $\Leftrightarrow \frac{1}{27}<3^{x}-1<3 \Leftrightarrow \frac{28}{27}<3^{x}<4$.

Answer: $\quad x \in\left(\log _{3} \frac{28}{27} ; \log _{3} 4\right)$.