There are 1 questions in this calculation: for each question, the 1 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ xt{e}^{(-3t)}\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( xt{e}^{(-3t)}\right)}{dt}\\=&x{e}^{(-3t)} + xt({e}^{(-3t)}((-3)ln(e) + \frac{(-3t)(0)}{(e)}))\\=&x{e}^{(-3t)} - 3xt{e}^{(-3t)}\\ \end{split}\end{equation} \]

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