There are 1 questions in this calculation: for each question, the 1 derivative of y is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 20sin(3x)y + {y}^{2}\ with\ respect\ to\ y：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 20ysin(3x) + y^{2}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 20ysin(3x) + y^{2}\right)}{dy}\\=&20sin(3x) + 20ycos(3x)*0 + 2y\\=&20sin(3x) + 2y\\ \end{split}\end{equation} \]

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