There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -0.0039{x}^{3} + 0.0746{x}^{2} - 0.4387x + 19.34\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -0.0039x^{3} + 0.0746x^{2} - 0.4387x + 19.34\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -0.0039x^{3} + 0.0746x^{2} - 0.4387x + 19.34\right)}{dx}\\=&-0.0039*3x^{2} + 0.0746*2x - 0.4387 + 0\\=&-0.0117x^{2} + 0.1492x - 0.4387\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -0.0117x^{2} + 0.1492x - 0.4387\right)}{dx}\\=&-0.0117*2x + 0.1492 + 0\\=&-0.0234x + 0.1492\\ \end{split}\end{equation} \]

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