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

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