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

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