There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ arctan(\frac{x}{2*\frac{1}{5}})*2*2*\frac{1}{5}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{4}{5}arctan(\frac{5}{2}x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{4}{5}arctan(\frac{5}{2}x)\right)}{dx}\\=&\frac{4}{5}(\frac{(\frac{5}{2})}{(1 + (\frac{5}{2}x)^{2})})\\=&\frac{2}{(\frac{25}{4}x^{2} + 1)}\\ \end{split}\end{equation} \]

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