There are 1 questions in this calculation: for each question, the 3 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ third\ derivative\ of\ function\ \frac{1}{(x*3 + 1)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{1}{(3x + 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{1}{(3x + 1)}\right)}{dx}\\=&(\frac{-(3 + 0)}{(3x + 1)^{2}})\\=&\frac{-3}{(3x + 1)^{2}}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-3}{(3x + 1)^{2}}\right)}{dx}\\=&-3(\frac{-2(3 + 0)}{(3x + 1)^{3}})\\=&\frac{18}{(3x + 1)^{3}}\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( \frac{18}{(3x + 1)^{3}}\right)}{dx}\\=&18(\frac{-3(3 + 0)}{(3x + 1)^{4}})\\=&\frac{-162}{(3x + 1)^{4}}\\ \end{split}\end{equation} \]

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