There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (1991.994 + 1513.5x)(4.09 - 2x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - 3983.988x + 6190.215x - 3027x^{2} + 8147.25546\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - 3983.988x + 6190.215x - 3027x^{2} + 8147.25546\right)}{dx}\\=& - 3983.988 + 6190.215 - 3027*2x + 0\\=& - 6054x + 2206.227\\ \end{split}\end{equation} \]

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