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

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