There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(13x + 18y)}{(19y - 1)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{13x}{(19y - 1)} + \frac{18y}{(19y - 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{13x}{(19y - 1)} + \frac{18y}{(19y - 1)}\right)}{dx}\\=&13(\frac{-(0 + 0)}{(19y - 1)^{2}})x + \frac{13}{(19y - 1)} + 18(\frac{-(0 + 0)}{(19y - 1)^{2}})y + 0\\=&\frac{13}{(19y - 1)}\\ \end{split}\end{equation} \]

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