There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ 0.0004{x}^{3} - 0.0249{x}^{2} + 0.4173x + 67.95\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 0.0004x^{3} - 0.0249x^{2} + 0.4173x + 67.95\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 0.0004x^{3} - 0.0249x^{2} + 0.4173x + 67.95\right)}{dx}\\=&0.0004*3x^{2} - 0.0249*2x + 0.4173 + 0\\=&0.0012x^{2} - 0.0498x + 0.4173\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 0.0012x^{2} - 0.0498x + 0.4173\right)}{dx}\\=&0.0012*2x - 0.0498 + 0\\=&0.0024x - 0.0498\\ \end{split}\end{equation} \]

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