There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ (\frac{-4}{3})e^{-3x}sin(3x) - 3sin(x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{-4}{3}e^{-3x}sin(3x) - 3sin(x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{-4}{3}e^{-3x}sin(3x) - 3sin(x)\right)}{dx}\\=&\frac{-4}{3}e^{-3x}*-3sin(3x) - \frac{4}{3}e^{-3x}cos(3x)*3 - 3cos(x)\\=&4e^{-3x}sin(3x) - 4e^{-3x}cos(3x) - 3cos(x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 4e^{-3x}sin(3x) - 4e^{-3x}cos(3x) - 3cos(x)\right)}{dx}\\=&4e^{-3x}*-3sin(3x) + 4e^{-3x}cos(3x)*3 - 4e^{-3x}*-3cos(3x) - 4e^{-3x}*-sin(3x)*3 - 3*-sin(x)\\=&24e^{-3x}cos(3x) + 3sin(x)\\ \end{split}\end{equation} \]

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