There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(6e^{-x})*2}{(1 + 3e^{-x})}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{12e^{-x}}{(3e^{-x} + 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{12e^{-x}}{(3e^{-x} + 1)}\right)}{dx}\\=&12(\frac{-(3e^{-x}*-1 + 0)}{(3e^{-x} + 1)^{2}})e^{-x} + \frac{12e^{-x}*-1}{(3e^{-x} + 1)}\\=&\frac{36e^{{-x}*{2}}}{(3e^{-x} + 1)^{2}} - \frac{12e^{-x}}{(3e^{-x} + 1)}\\ \end{split}\end{equation} \]

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