There are 1 questions in this calculation: for each question, the 1 derivative of y is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(\frac{sin(2)x}{2} - xcos(2x))}{2}\ with\ respect\ to\ y：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{1}{4}xsin(2) - \frac{1}{2}xcos(2x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{1}{4}xsin(2) - \frac{1}{2}xcos(2x)\right)}{dy}\\=&\frac{1}{4}xcos(2)*0 - \frac{1}{2}x*-sin(2x)*0\\=&\frac{0}{2}\\ \end{split}\end{equation} \]

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