There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ 0.0009{x}^{3} - 0.0279{x}^{2} + 0.3406x + 13.779\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 0.0009x^{3} - 0.0279x^{2} + 0.3406x + 13.779\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 0.0009x^{3} - 0.0279x^{2} + 0.3406x + 13.779\right)}{dx}\\=&0.0009*3x^{2} - 0.0279*2x + 0.3406 + 0\\=&0.0027x^{2} - 0.0558x + 0.3406\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 0.0027x^{2} - 0.0558x + 0.3406\right)}{dx}\\=&0.0027*2x - 0.0558 + 0\\=&0.0054x - 0.0558\\ \end{split}\end{equation} \]

Your problem has not been solved here? Please take a look at the  hot problems ！