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

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