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

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