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

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