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

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