There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{ln(cos(x))}{ln(cos(3x))}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{ln(cos(x))}{ln(cos(3x))}\right)}{dx}\\=&\frac{-sin(x)}{(cos(x))ln(cos(3x))} + \frac{ln(cos(x))*--sin(3x)*3}{ln^{2}(cos(3x))(cos(3x))}\\=&\frac{-sin(x)}{ln(cos(3x))cos(x)} + \frac{3ln(cos(x))sin(3x)}{ln^{2}(cos(3x))cos(3x)}\\ \end{split}\end{equation} \]

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