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

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