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

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