There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ r - sqrt({r}^{2} - 25)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = r - sqrt(r^{2} - 25)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( r - sqrt(r^{2} - 25)\right)}{dx}\\=&0 - \frac{(0 + 0)*\frac{1}{2}}{(r^{2} - 25)^{\frac{1}{2}}}\\=& - \frac{0}{2}\\ \end{split}\end{equation} \]

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