There are 1 questions in this calculation: for each question, the 1 derivative of r is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 3.14rsqrt({r}^{2} + 99*99 * {\frac{1}{3.14}}^{2}{\frac{1}{r}}^{4})\ with\ respect\ to\ r：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 3.14rsqrt(\frac{3121.33757961783}{r} + r)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 3.14rsqrt(\frac{3121.33757961783}{r} + r)\right)}{dr}\\=&3.14sqrt(\frac{3121.33757961783}{r} + r) + \frac{3.14r(\frac{3121.33757961783*-1}{r^{2}} + 1)*0.5}{(\frac{3121.33757961783}{r} + r)^{\frac{1}{2}}}\\=&3.14sqrt(\frac{3121.33757961783}{r} + r) - \frac{4900.5}{(\frac{3121.33757961783}{r} + r)^{\frac{1}{2}}r} + \frac{1.57r}{(\frac{3121.33757961783}{r} + r)^{\frac{1}{2}}}\\ \end{split}\end{equation} \]

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