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

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