There are 1 questions in this calculation: for each question, the 1 derivative of a is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{7.77a}{(7.77a + 50)}\ with\ respect\ to\ a：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{7.77a}{(7.77a + 50)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{7.77a}{(7.77a + 50)}\right)}{da}\\=&7.77(\frac{-(7.77 + 0)}{(7.77a + 50)^{2}})a + \frac{7.77}{(7.77a + 50)}\\=&\frac{-60.3729a}{(7.77a + 50)(7.77a + 50)} + \frac{7.77}{(7.77a + 50)}\\ \end{split}\end{equation} \]

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