There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ (\frac{π}{2} - arctan(4){x}^{2})x\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{1}{2}πx - x^{3}arctan(4)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{1}{2}πx - x^{3}arctan(4)\right)}{dx}\\=&\frac{1}{2}π - 3x^{2}arctan(4) - x^{3}(\frac{(0)}{(1 + (4)^{2})})\\=&\frac{π}{2} - 3x^{2}arctan(4)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{π}{2} - 3x^{2}arctan(4)\right)}{dx}\\=&0 - 3*2xarctan(4) - 3x^{2}(\frac{(0)}{(1 + (4)^{2})})\\=& - 6xarctan(4)\\ \end{split}\end{equation} \]

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