There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -e^{-5x}(x - 4)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -xe^{-5x} + 4e^{-5x}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -xe^{-5x} + 4e^{-5x}\right)}{dx}\\=&-e^{-5x} - xe^{-5x}*-5 + 4e^{-5x}*-5\\=&-21e^{-5x} + 5xe^{-5x}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -21e^{-5x} + 5xe^{-5x}\right)}{dx}\\=&-21e^{-5x}*-5 + 5e^{-5x} + 5xe^{-5x}*-5\\=&110e^{-5x} - 25xe^{-5x}\\ \end{split}\end{equation} \]

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