There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (\frac{20}{cos(\frac{1}{2}pi - x)}){(45 + 36(cos(pi - x)))}^{\frac{1}{2}}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{20(36cos(pi - x) + 45)^{\frac{1}{2}}}{cos(\frac{1}{2}pi - x)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{20(36cos(pi - x) + 45)^{\frac{1}{2}}}{cos(\frac{1}{2}pi - x)}\right)}{dx}\\=&\frac{20(\frac{\frac{1}{2}(36*-sin(pi - x)(0 - 1) + 0)}{(36cos(pi - x) + 45)^{\frac{1}{2}}})}{cos(\frac{1}{2}pi - x)} + \frac{20(36cos(pi - x) + 45)^{\frac{1}{2}}sin(\frac{1}{2}pi - x)(0 - 1)}{cos^{2}(\frac{1}{2}pi - x)}\\=&\frac{360sin(pi - x)}{(36cos(pi - x) + 45)^{\frac{1}{2}}cos(\frac{1}{2}pi - x)} - \frac{20(36cos(pi - x) + 45)^{\frac{1}{2}}sin(\frac{1}{2}pi - x)}{cos^{2}(\frac{1}{2}pi - x)}\\ \end{split}\end{equation} \]

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