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

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