There are 1 questions in this calculation: for each question, the 1 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{400}{(1 + 399{e}^{(-0.02806(174.28 + t))})}\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{400}{(399{e}^{(-0.02806t - 4.8902968)} + 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{400}{(399{e}^{(-0.02806t - 4.8902968)} + 1)}\right)}{dt}\\=&400(\frac{-(399({e}^{(-0.02806t - 4.8902968)}((-0.02806 + 0)ln(e) + \frac{(-0.02806t - 4.8902968)(0)}{(e)})) + 0)}{(399{e}^{(-0.02806t - 4.8902968)} + 1)^{2}})\\=&\frac{4478.376{e}^{(-0.02806t - 4.8902968)}}{(399{e}^{(-0.02806t - 4.8902968)} + 1)(399{e}^{(-0.02806t - 4.8902968)} + 1)}\\ \end{split}\end{equation} \]

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