There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -0.0003{x}^{3} + 0.0046{x}^{2} + 0.0093x + 21.987\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -0.0003x^{3} + 0.0046x^{2} + 0.0093x + 21.987\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -0.0003x^{3} + 0.0046x^{2} + 0.0093x + 21.987\right)}{dx}\\=&-0.0003*3x^{2} + 0.0046*2x + 0.0093 + 0\\=&-0.0009x^{2} + 0.0092x + 0.0093\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -0.0009x^{2} + 0.0092x + 0.0093\right)}{dx}\\=&-0.0009*2x + 0.0092 + 0\\=&-0.0018x + 0.0092\\ \end{split}\end{equation} \]

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