There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ x{\frac{1}{(x + 3)}}^{2}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{x}{(x + 3)^{2}}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{x}{(x + 3)^{2}}\right)}{dx}\\=&(\frac{-2(1 + 0)}{(x + 3)^{3}})x + \frac{1}{(x + 3)^{2}}\\=&\frac{-2x}{(x + 3)^{3}} + \frac{1}{(x + 3)^{2}}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-2x}{(x + 3)^{3}} + \frac{1}{(x + 3)^{2}}\right)}{dx}\\=&-2(\frac{-3(1 + 0)}{(x + 3)^{4}})x - \frac{2}{(x + 3)^{3}} + (\frac{-2(1 + 0)}{(x + 3)^{3}})\\=&\frac{6x}{(x + 3)^{4}} - \frac{4}{(x + 3)^{3}}\\ \end{split}\end{equation} \]

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