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

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