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

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