There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{-3cos(2x)}{4} + \frac{{(cos(2x))}^{2}}{8}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{-3}{4}cos(2x) + \frac{1}{8}cos^{2}(2x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{-3}{4}cos(2x) + \frac{1}{8}cos^{2}(2x)\right)}{dx}\\=&\frac{-3}{4}*-sin(2x)*2 + \frac{1}{8}*-2cos(2x)sin(2x)*2\\=& - \frac{sin(2x)cos(2x)}{2} + \frac{3sin(2x)}{2}\\ \end{split}\end{equation} \]

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