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

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