There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ x(1 - (\frac{1}{5})ln(\frac{x}{5}))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - \frac{1}{5}xln(\frac{1}{5}x) + x\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - \frac{1}{5}xln(\frac{1}{5}x) + x\right)}{dx}\\=& - \frac{1}{5}ln(\frac{1}{5}x) - \frac{\frac{1}{5}x*\frac{1}{5}}{(\frac{1}{5}x)} + 1\\=& - \frac{ln(\frac{1}{5}x)}{5} + \frac{4}{5}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( - \frac{ln(\frac{1}{5}x)}{5} + \frac{4}{5}\right)}{dx}\\=& - \frac{\frac{1}{5}}{5(\frac{1}{5}x)} + 0\\=& - \frac{1}{5x}\\ \end{split}\end{equation} \]

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