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

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