There are 1 questions in this calculation: for each question, the 2 derivative of R is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ 12544R{\frac{1}{(36 + R)}}^{2}\ with\ respect\ to\ R：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{12544R}{(R + 36)^{2}}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{12544R}{(R + 36)^{2}}\right)}{dR}\\=&12544(\frac{-2(1 + 0)}{(R + 36)^{3}})R + \frac{12544}{(R + 36)^{2}}\\=&\frac{-25088R}{(R + 36)^{3}} + \frac{12544}{(R + 36)^{2}}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-25088R}{(R + 36)^{3}} + \frac{12544}{(R + 36)^{2}}\right)}{dR}\\=&-25088(\frac{-3(1 + 0)}{(R + 36)^{4}})R - \frac{25088}{(R + 36)^{3}} + 12544(\frac{-2(1 + 0)}{(R + 36)^{3}})\\=&\frac{75264R}{(R + 36)^{4}} - \frac{50176}{(R + 36)^{3}}\\ \end{split}\end{equation} \]

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