<s>[INST] Simple use of log I am struggling to see how we can go from the first expression to the second:
$$\begin{align}
2\log_3 12 - 4\log_3 6 &= \log_3 \left ( \frac{4^2 \cdot 3^2}{2^4 \cdot 3^4} \right )\\
&= \log_3 (3^{-2}) = -2
\end{align}$$
 [/INST] Remember, $$\log ab = \log a + \log b$$
and
$$m\log a=\log a^m.$$
HINT:
$$12^2 = (4\cdot 3)^2=4^2\cdot 3^2.$$
Similarly,
$$6^4 = (2\cdot 3)^4 = 2^4\cdot 3^4$$
I think you can take it from here.
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