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

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