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

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