There are 1 questions in this calculation: for each question, the 1 derivative of t is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (sin(wt)) + (\frac{(Lwcos(wt))}{4})\ with\ respect\ to\ t：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = sin(wt) + \frac{1}{4}wLcos(wt)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( sin(wt) + \frac{1}{4}wLcos(wt)\right)}{dt}\\=&cos(wt)w + \frac{1}{4}wL*-sin(wt)w\\=&wcos(wt) - \frac{w^{2}Lsin(wt)}{4}\\ \end{split}\end{equation} \]

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