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

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