There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -0.0009{x}^{3} + 0.0222{x}^{2} - 0.0726x + 8.1616\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -0.0009x^{3} + 0.0222x^{2} - 0.0726x + 8.1616\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -0.0009x^{3} + 0.0222x^{2} - 0.0726x + 8.1616\right)}{dx}\\=&-0.0009*3x^{2} + 0.0222*2x - 0.0726 + 0\\=&-0.0027x^{2} + 0.0444x - 0.0726\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -0.0027x^{2} + 0.0444x - 0.0726\right)}{dx}\\=&-0.0027*2x + 0.0444 + 0\\=&-0.0054x + 0.0444\\ \end{split}\end{equation} \]

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