There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{3x}{({x}^{2} - 1)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{3x}{(x^{2} - 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{3x}{(x^{2} - 1)}\right)}{dx}\\=&3(\frac{-(2x + 0)}{(x^{2} - 1)^{2}})x + \frac{3}{(x^{2} - 1)}\\=&\frac{-6x^{2}}{(x^{2} - 1)^{2}} + \frac{3}{(x^{2} - 1)}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-6x^{2}}{(x^{2} - 1)^{2}} + \frac{3}{(x^{2} - 1)}\right)}{dx}\\=&-6(\frac{-2(2x + 0)}{(x^{2} - 1)^{3}})x^{2} - \frac{6*2x}{(x^{2} - 1)^{2}} + 3(\frac{-(2x + 0)}{(x^{2} - 1)^{2}})\\=&\frac{24x^{3}}{(x^{2} - 1)^{3}} - \frac{18x}{(x^{2} - 1)^{2}}\\ \end{split}\end{equation} \]

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