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

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