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

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