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

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