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

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