There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -3x*3(3x + 9)*2 + 3x*2(3x + 9) - 12x*2(3x + 9)*2 + 8x(3x + 9) - 9x(3x + 9)*2 + 3(3x + 9)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -210x^{2} - 621x + 27\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -210x^{2} - 621x + 27\right)}{dx}\\=&-210*2x - 621 + 0\\=&-420x - 621\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -420x - 621\right)}{dx}\\=&-420 + 0\\=&-420\\ \end{split}\end{equation} \]

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