There are 1 questions in this calculation: for each question, the 1 derivative of a is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 1 - \frac{1}{(220 + \frac{1}{2}a)} - \frac{1}{(220 - \frac{1}{10}a)}\ with\ respect\ to\ a：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - \frac{1}{(\frac{1}{2}a + 220)} - \frac{1}{(\frac{-1}{10}a + 220)} + 1\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( - \frac{1}{(\frac{1}{2}a + 220)} - \frac{1}{(\frac{-1}{10}a + 220)} + 1\right)}{da}\\=& - (\frac{-(\frac{1}{2} + 0)}{(\frac{1}{2}a + 220)^{2}}) - (\frac{-(\frac{-1}{10} + 0)}{(\frac{-1}{10}a + 220)^{2}}) + 0\\=&\frac{1}{2(\frac{1}{2}a + 220)^{2}} - \frac{1}{10(\frac{-1}{10}a + 220)^{2}}\\ \end{split}\end{equation} \]

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