There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 5cos(2pit) + 2cos(4.1716pit)cos(2pit) - 2*0.9603sin(4.1716pit)sin(2pit)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 2cos(4.1716pit)cos(2pit) + 5cos(2pit) - 1.9206sin(4.1716pit)sin(2pit)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 2cos(4.1716pit)cos(2pit) + 5cos(2pit) - 1.9206sin(4.1716pit)sin(2pit)\right)}{dx}\\=&2*-sin(4.1716pit)*0cos(2pit) + 2cos(4.1716pit)*-sin(2pit)*0 + 5*-sin(2pit)*0 - 1.9206cos(4.1716pit)*0sin(2pit) - 1.9206sin(4.1716pit)cos(2pit)*0\\=&0\\ \end{split}\end{equation} \]

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