There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{25}{(\frac{12}{x} + 3)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{25}{(\frac{12}{x} + 3)}\right)}{dx}\\=&25(\frac{-(\frac{12*-1}{x^{2}} + 0)}{(\frac{12}{x} + 3)^{2}})\\=&\frac{300}{(\frac{12}{x} + 3)^{2}x^{2}}\\ \end{split}\end{equation} \]

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