There are 1 questions in this calculation: for each question, the 1 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(tcos(t)abs(sin(t)))(cos(t))}{abs}\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = tsin(t)cos^{2}(t)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( tsin(t)cos^{2}(t)\right)}{dt}\\=&sin(t)cos^{2}(t) + tcos(t)cos^{2}(t) + tsin(t)*-2cos(t)sin(t)\\=&sin(t)cos^{2}(t) + tcos^{3}(t) - 2tsin^{2}(t)cos(t)\\ \end{split}\end{equation} \]

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