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

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