There are 1 questions in this calculation: for each question, the 1 derivative of d is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{G{d}^{4}}{(80{D}^{3})}\ with\ respect\ to\ d：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{\frac{1}{80}Gd^{4}}{D^{3}}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{\frac{1}{80}Gd^{4}}{D^{3}}\right)}{dd}\\=&\frac{\frac{1}{80}G*4d^{3}}{D^{3}}\\=&\frac{Gd^{3}}{20D^{3}}\\ \end{split}\end{equation} \]

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