There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{{x}^{2}}{(1 - {x}^{2})}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{x^{2}}{(-x^{2} + 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{x^{2}}{(-x^{2} + 1)}\right)}{dx}\\=&(\frac{-(-2x + 0)}{(-x^{2} + 1)^{2}})x^{2} + \frac{2x}{(-x^{2} + 1)}\\=&\frac{2x^{3}}{(-x^{2} + 1)^{2}} + \frac{2x}{(-x^{2} + 1)}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{2x^{3}}{(-x^{2} + 1)^{2}} + \frac{2x}{(-x^{2} + 1)}\right)}{dx}\\=&2(\frac{-2(-2x + 0)}{(-x^{2} + 1)^{3}})x^{3} + \frac{2*3x^{2}}{(-x^{2} + 1)^{2}} + 2(\frac{-(-2x + 0)}{(-x^{2} + 1)^{2}})x + \frac{2}{(-x^{2} + 1)}\\=&\frac{8x^{4}}{(-x^{2} + 1)^{3}} + \frac{10x^{2}}{(-x^{2} + 1)^{2}} + \frac{2}{(-x^{2} + 1)}\\ \end{split}\end{equation} \]

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