There are 1 questions in this calculation: for each question, the 1 derivative of V is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ rt{\frac{1}{(V - b)}}^{2}\ with\ respect\ to\ V：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{rt}{(V - b)^{2}}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{rt}{(V - b)^{2}}\right)}{dV}\\=&(\frac{-2(1 + 0)}{(V - b)^{3}})rt + 0\\=&\frac{-2rt}{(V - b)^{3}}\\ \end{split}\end{equation} \]

Your problem has not been solved here? Please take a look at the  hot problems ！