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

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