There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ x - \frac{({x}^{3} + 4x - 1)}{(3{x}^{2} + 4)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = x - \frac{x^{3}}{(3x^{2} + 4)} - \frac{4x}{(3x^{2} + 4)} + \frac{1}{(3x^{2} + 4)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( x - \frac{x^{3}}{(3x^{2} + 4)} - \frac{4x}{(3x^{2} + 4)} + \frac{1}{(3x^{2} + 4)}\right)}{dx}\\=&1 - (\frac{-(3*2x + 0)}{(3x^{2} + 4)^{2}})x^{3} - \frac{3x^{2}}{(3x^{2} + 4)} - 4(\frac{-(3*2x + 0)}{(3x^{2} + 4)^{2}})x - \frac{4}{(3x^{2} + 4)} + (\frac{-(3*2x + 0)}{(3x^{2} + 4)^{2}})\\=&\frac{6x^{4}}{(3x^{2} + 4)^{2}} - \frac{3x^{2}}{(3x^{2} + 4)} + \frac{24x^{2}}{(3x^{2} + 4)^{2}} - \frac{6x}{(3x^{2} + 4)^{2}} - \frac{4}{(3x^{2} + 4)} + 1\\ \end{split}\end{equation} \]

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