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

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