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

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