There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ 0.0139{x}^{3} - 0.3359{x}^{2} + 2.5394x + 20.339\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 0.0139x^{3} - 0.3359x^{2} + 2.5394x + 20.339\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 0.0139x^{3} - 0.3359x^{2} + 2.5394x + 20.339\right)}{dx}\\=&0.0139*3x^{2} - 0.3359*2x + 2.5394 + 0\\=&0.0417x^{2} - 0.6718x + 2.5394\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 0.0417x^{2} - 0.6718x + 2.5394\right)}{dx}\\=&0.0417*2x - 0.6718 + 0\\=&0.0834x - 0.6718\\ \end{split}\end{equation} \]

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