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

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