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

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