There are 1 questions in this calculation: for each question, the 1 derivative of a is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ (1350 - a)(51 + \frac{3a}{20})\ with\ respect\ to\ a：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{303}{2}a - \frac{3}{20}a^{2} + 68850\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{303}{2}a - \frac{3}{20}a^{2} + 68850\right)}{da}\\=&\frac{303}{2} - \frac{3}{20}*2a + 0\\=& - \frac{3a}{10} + \frac{303}{2}\\ \end{split}\end{equation} \]

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