There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (5 - 4sin(x))(5 - 4cos(x))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - 20cos(x) + 16sin(x)cos(x) - 20sin(x) + 25\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - 20cos(x) + 16sin(x)cos(x) - 20sin(x) + 25\right)}{dx}\\=& - 20*-sin(x) + 16cos(x)cos(x) + 16sin(x)*-sin(x) - 20cos(x) + 0\\=& - 16sin^{2}(x) + 16cos^{2}(x) + 20sin(x) - 20cos(x)\\ \end{split}\end{equation} \]

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