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

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