There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ 0.0021{x}^{3} - 0.0314{x}^{2} + 0.1691x + 6.2764\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 0.0021x^{3} - 0.0314x^{2} + 0.1691x + 6.2764\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 0.0021x^{3} - 0.0314x^{2} + 0.1691x + 6.2764\right)}{dx}\\=&0.0021*3x^{2} - 0.0314*2x + 0.1691 + 0\\=&0.0063x^{2} - 0.0628x + 0.1691\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 0.0063x^{2} - 0.0628x + 0.1691\right)}{dx}\\=&0.0063*2x - 0.0628 + 0\\=&0.0126x - 0.0628\\ \end{split}\end{equation} \]

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