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

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