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

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