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

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