There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ cos(π(b{\frac{1}{x}}^{20}))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = cos(\frac{πb}{x^{20}})\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( cos(\frac{πb}{x^{20}})\right)}{dx}\\=&\frac{-sin(\frac{πb}{x^{20}})πb*-20}{x^{21}}\\=&\frac{20πbsin(\frac{πb}{x^{20}})}{x^{21}}\\ \end{split}\end{equation} \]

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