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

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