There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (-83x + 9)cos(5x + 1)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -83xcos(5x + 1) + 9cos(5x + 1)\right)}{dx}\\=&-83cos(5x + 1) - 83x*-sin(5x + 1)(5 + 0) + 9*-sin(5x + 1)(5 + 0)\\=&-83cos(5x + 1) + 415xsin(5x + 1) - 45sin(5x + 1)\\ \end{split}\end{equation} \]

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