There are 1 questions in this calculation: for each question, the 1 derivative of y is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{3y}{(y + cos(x))}\ with\ respect\ to\ y：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{3y}{(y + cos(x))}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{3y}{(y + cos(x))}\right)}{dy}\\=&3(\frac{-(1 + -sin(x)*0)}{(y + cos(x))^{2}})y + \frac{3}{(y + cos(x))}\\=&\frac{-3y}{(y + cos(x))^{2}} + \frac{3}{(y + cos(x))}\\ \end{split}\end{equation} \]

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