There are 1 questions in this calculation: for each question, the 2 derivative of r is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{be^{-r}}{(4dcr)}\ with\ respect\ to\ r：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{\frac{1}{4}be^{-r}}{dcr}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{\frac{1}{4}be^{-r}}{dcr}\right)}{dr}\\=&\frac{\frac{1}{4}b*-e^{-r}}{dcr^{2}} + \frac{\frac{1}{4}be^{-r}*-1}{dcr}\\=&\frac{-be^{-r}}{4dcr^{2}} - \frac{be^{-r}}{4dcr}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-be^{-r}}{4dcr^{2}} - \frac{be^{-r}}{4dcr}\right)}{dr}\\=&\frac{-b*-2e^{-r}}{4dcr^{3}} - \frac{be^{-r}*-1}{4dcr^{2}} - \frac{b*-e^{-r}}{4dcr^{2}} - \frac{be^{-r}*-1}{4dcr}\\=&\frac{be^{-r}}{2dcr^{3}} + \frac{be^{-r}}{2dcr^{2}} + \frac{be^{-r}}{4dcr}\\ \end{split}\end{equation} \]

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