There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (1 - \frac{(7640 + 12x)}{(7890 + 12x)})*250000 - 200\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - \frac{3000000x}{(12x + 7890)} - \frac{1910000000}{(12x + 7890)} + 249800\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - \frac{3000000x}{(12x + 7890)} - \frac{1910000000}{(12x + 7890)} + 249800\right)}{dx}\\=& - 3000000(\frac{-(12 + 0)}{(12x + 7890)^{2}})x - \frac{3000000}{(12x + 7890)} - 1910000000(\frac{-(12 + 0)}{(12x + 7890)^{2}}) + 0\\=&\frac{36000000x}{(12x + 7890)^{2}} + \frac{22920000000}{(12x + 7890)^{2}} - \frac{3000000}{(12x + 7890)}\\ \end{split}\end{equation} \]

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