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

Your problem has not been solved here? Please take a look at the  hot problems ！