There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(cos(x) - xsin(x))}{(sin(x) + xcos(x))}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{cos(x)}{(sin(x) + xcos(x))} - \frac{xsin(x)}{(sin(x) + xcos(x))}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{cos(x)}{(sin(x) + xcos(x))} - \frac{xsin(x)}{(sin(x) + xcos(x))}\right)}{dx}\\=&(\frac{-(cos(x) + cos(x) + x*-sin(x))}{(sin(x) + xcos(x))^{2}})cos(x) + \frac{-sin(x)}{(sin(x) + xcos(x))} - (\frac{-(cos(x) + cos(x) + x*-sin(x))}{(sin(x) + xcos(x))^{2}})xsin(x) - \frac{sin(x)}{(sin(x) + xcos(x))} - \frac{xcos(x)}{(sin(x) + xcos(x))}\\=&\frac{-2cos^{2}(x)}{(sin(x) + xcos(x))^{2}} + \frac{3xsin(x)cos(x)}{(sin(x) + xcos(x))^{2}} - \frac{2sin(x)}{(sin(x) + xcos(x))} - \frac{x^{2}sin^{2}(x)}{(sin(x) + xcos(x))^{2}} - \frac{xcos(x)}{(sin(x) + xcos(x))}\\ \end{split}\end{equation} \]

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