There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{6x}{(x + 20)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{6x}{(x + 20)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{6x}{(x + 20)}\right)}{dx}\\=&6(\frac{-(1 + 0)}{(x + 20)^{2}})x + \frac{6}{(x + 20)}\\=&\frac{-6x}{(x + 20)^{2}} + \frac{6}{(x + 20)}\\ \end{split}\end{equation} \]

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