There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 20sqrt(6) + 21.65 - 21.65cos(3x)cos(x) - 10sin(x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 20sqrt(6) - 21.65cos(3x)cos(x) - 10sin(x) + 21.65\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 20sqrt(6) - 21.65cos(3x)cos(x) - 10sin(x) + 21.65\right)}{dx}\\=&20*0*0.5*6^{\frac{1}{2}} - 21.65*-sin(3x)*3cos(x) - 21.65cos(3x)*-sin(x) - 10cos(x) + 0\\=& - -64.95sin(3x)cos(x) + 21.65sin(x)cos(3x) - 10cos(x)\\ \end{split}\end{equation} \]

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