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

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