There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 6xcos(5x) - 15{x}^{2}sin(5x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 6xcos(5x) - 15x^{2}sin(5x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 6xcos(5x) - 15x^{2}sin(5x)\right)}{dx}\\=&6cos(5x) + 6x*-sin(5x)*5 - 15*2xsin(5x) - 15x^{2}cos(5x)*5\\=&6cos(5x) - 60xsin(5x) - 75x^{2}cos(5x)\\ \end{split}\end{equation} \]

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