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

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