There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{cos(x)}{cos(60 - x)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{cos(x)}{cos(-x + 60)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{cos(x)}{cos(-x + 60)}\right)}{dx}\\=&\frac{-sin(x)}{cos(-x + 60)} + \frac{cos(x)sin(-x + 60)(-1 + 0)}{cos^{2}(-x + 60)}\\=&\frac{-sin(-x + 60)cos(x)}{cos^{2}(-x + 60)} - \frac{sin(x)}{cos(-x + 60)}\\ \end{split}\end{equation} \]

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