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

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