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

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