There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ e^{-4x} + xe^{-4x}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( e^{-4x} + xe^{-4x}\right)}{dx}\\=&e^{-4x}*-4 + e^{-4x} + xe^{-4x}*-4\\=&-3e^{-4x} - 4xe^{-4x}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -3e^{-4x} - 4xe^{-4x}\right)}{dx}\\=&-3e^{-4x}*-4 - 4e^{-4x} - 4xe^{-4x}*-4\\=&8e^{-4x} + 16xe^{-4x}\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( 8e^{-4x} + 16xe^{-4x}\right)}{dx}\\=&8e^{-4x}*-4 + 16e^{-4x} + 16xe^{-4x}*-4\\=&-16e^{-4x} - 64xe^{-4x}\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( -16e^{-4x} - 64xe^{-4x}\right)}{dx}\\=&-16e^{-4x}*-4 - 64e^{-4x} - 64xe^{-4x}*-4\\=&256xe^{-4x}\\ \end{split}\end{equation} \]

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