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

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