There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -72x(x + 3)*3 + 36(x + 3)*2\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -216x^{2} - 576x + 216\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -216x^{2} - 576x + 216\right)}{dx}\\=&-216*2x - 576 + 0\\=&-432x - 576\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -432x - 576\right)}{dx}\\=&-432 + 0\\=&-432\\ \end{split}\end{equation} \]

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