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

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