There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{2}{5}{(cos(x))}^{\frac{2}{5}}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{2}{5}cos^{\frac{2}{5}}(x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{2}{5}cos^{\frac{2}{5}}(x)\right)}{dx}\\=&\frac{\frac{2}{5}*\frac{-2}{5}sin(x)}{cos^{\frac{3}{5}}(x)}\\=&\frac{-4sin(x)}{25cos^{\frac{3}{5}}(x)}\\ \end{split}\end{equation} \]

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