There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{-x}{(C + {x}^{2})}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{-x}{(C + x^{2})}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{-x}{(C + x^{2})}\right)}{dx}\\=&-(\frac{-(0 + 2x)}{(C + x^{2})^{2}})x - \frac{1}{(C + x^{2})}\\=&\frac{2x^{2}}{(C + x^{2})^{2}} - \frac{1}{(C + x^{2})}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{2x^{2}}{(C + x^{2})^{2}} - \frac{1}{(C + x^{2})}\right)}{dx}\\=&2(\frac{-2(0 + 2x)}{(C + x^{2})^{3}})x^{2} + \frac{2*2x}{(C + x^{2})^{2}} - (\frac{-(0 + 2x)}{(C + x^{2})^{2}})\\=&\frac{-8x^{3}}{(C + x^{2})^{3}} + \frac{6x}{(C + x^{2})^{2}}\\ \end{split}\end{equation} \]

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