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

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