There are 1 questions in this calculation: for each question, the 2 derivative of s is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{1}{(s(s + 3))}\ with\ respect\ to\ s：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{1}{(s^{2} + 3s)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{1}{(s^{2} + 3s)}\right)}{ds}\\=&(\frac{-(2s + 3)}{(s^{2} + 3s)^{2}})\\=&\frac{-2s}{(s^{2} + 3s)^{2}} - \frac{3}{(s^{2} + 3s)^{2}}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-2s}{(s^{2} + 3s)^{2}} - \frac{3}{(s^{2} + 3s)^{2}}\right)}{ds}\\=&-2(\frac{-2(2s + 3)}{(s^{2} + 3s)^{3}})s - \frac{2}{(s^{2} + 3s)^{2}} - 3(\frac{-2(2s + 3)}{(s^{2} + 3s)^{3}})\\=&\frac{8s^{2}}{(s^{2} + 3s)^{3}} + \frac{24s}{(s^{2} + 3s)^{3}} - \frac{2}{(s^{2} + 3s)^{2}} + \frac{18}{(s^{2} + 3s)^{3}}\\ \end{split}\end{equation} \]

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