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

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