<s>[INST] Inverse of an exponential function I am having difficulties forming the inverse of this
$f(x) = 3 \cdot2^{3x+1} \cdot 5^{3x-1}$.
What I have done so far:
$3 \cdot 2^{3y} \cdot 2^1 \cdot 5^{3y}\cdot5^{-1} \Leftrightarrow 3\cdot 2\cdot \frac{1}{5}\cdot (5\cdot 2)^{3y} \Leftrightarrow \frac{6}{5}\cdot 10^{3y} \Leftrightarrow \ln \frac{6}{5}\cdot \ln10\cdot 3y$
 [/INST] $x = \frac{\log \left(\frac{y}{6}\right)+\log (5)}{3 (\log (2)+\log (5))}$.
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