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

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