There are 1 questions in this calculation: for each question, the 1 derivative of D is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{(G{d}^{4})}{(8N{D}^{3})}\ with\ respect\ to\ D：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{\frac{1}{8}Gd^{4}}{ND^{3}}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{\frac{1}{8}Gd^{4}}{ND^{3}}\right)}{dD}\\=&\frac{\frac{1}{8}Gd^{4}*-3}{ND^{4}}\\=&\frac{-3Gd^{4}}{8ND^{4}}\\ \end{split}\end{equation} \]

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