There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{4sin(x)cos(x)}{(sin(x) + cos(x))}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{4sin(x)cos(x)}{(sin(x) + cos(x))}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{4sin(x)cos(x)}{(sin(x) + cos(x))}\right)}{dx}\\=&4(\frac{-(cos(x) + -sin(x))}{(sin(x) + cos(x))^{2}})sin(x)cos(x) + \frac{4cos(x)cos(x)}{(sin(x) + cos(x))} + \frac{4sin(x)*-sin(x)}{(sin(x) + cos(x))}\\=&\frac{-4sin(x)cos^{2}(x)}{(sin(x) + cos(x))^{2}} + \frac{4sin^{2}(x)cos(x)}{(sin(x) + cos(x))^{2}} + \frac{4cos^{2}(x)}{(sin(x) + cos(x))} - \frac{4sin^{2}(x)}{(sin(x) + cos(x))}\\ \end{split}\end{equation} \]

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