There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(300 - 75000x)}{(0.000075 - x)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - \frac{75000x}{(-x + 0.000075)} + \frac{300}{(-x + 0.000075)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - \frac{75000x}{(-x + 0.000075)} + \frac{300}{(-x + 0.000075)}\right)}{dx}\\=& - 75000(\frac{-(-1 + 0)}{(-x + 0.000075)^{2}})x - \frac{75000}{(-x + 0.000075)} + 300(\frac{-(-1 + 0)}{(-x + 0.000075)^{2}})\\=& - \frac{75000x}{(-x + 0.000075)(-x + 0.000075)} + \frac{300}{(-x + 0.000075)(-x + 0.000075)} - \frac{75000}{(-x + 0.000075)}\\ \end{split}\end{equation} \]

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