There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ ln(20000 - 15000x) + ln(28000x + 12000)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = ln(-15000x + 20000) + ln(28000x + 12000)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( ln(-15000x + 20000) + ln(28000x + 12000)\right)}{dx}\\=&\frac{(-15000 + 0)}{(-15000x + 20000)} + \frac{(28000 + 0)}{(28000x + 12000)}\\=&\frac{-15000}{(-15000x + 20000)} + \frac{28000}{(28000x + 12000)}\\ \end{split}\end{equation} \]

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