There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ log_{3}^{7x}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( log_{3}^{7x}\right)}{dx}\\=&(\frac{(\frac{(7)}{(7x)} - \frac{(0)log_{3}^{7x}}{(3)})}{(ln(3))})\\=&\frac{1}{xln(3)}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{1}{xln(3)}\right)}{dx}\\=&\frac{-1}{x^{2}ln(3)} + \frac{-0}{xln^{2}(3)(3)}\\=&\frac{-1}{x^{2}ln(3)}\\ \end{split}\end{equation} \]

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