There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ arccos(\frac{75}{x}) + arccos(\frac{\frac{65}{2}}{x})\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( arccos(\frac{75}{x}) + arccos(\frac{\frac{65}{2}}{x})\right)}{dx}\\=&(\frac{-(\frac{75*-1}{x^{2}})}{((1 - (\frac{75}{x})^{2})^{\frac{1}{2}})}) + (\frac{-(\frac{\frac{65}{2}*-1}{x^{2}})}{((1 - (\frac{\frac{65}{2}}{x})^{2})^{\frac{1}{2}})})\\=&\frac{75}{(\frac{-5625}{x^{2}} + 1)^{\frac{1}{2}}x^{2}} + \frac{65}{2(\frac{\frac{-4225}{4}}{x^{2}} + 1)^{\frac{1}{2}}x^{2}}\\ \end{split}\end{equation} \]

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