There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ \frac{({n}^{2} + 4n + 19)}{(2n + 1)}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{n^{2}}{(2n + 1)} + \frac{4n}{(2n + 1)} + \frac{19}{(2n + 1)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{n^{2}}{(2n + 1)} + \frac{4n}{(2n + 1)} + \frac{19}{(2n + 1)}\right)}{dx}\\=&(\frac{-(0 + 0)}{(2n + 1)^{2}})n^{2} + 0 + 4(\frac{-(0 + 0)}{(2n + 1)^{2}})n + 0 + 19(\frac{-(0 + 0)}{(2n + 1)^{2}})\\=& - 0\\ \end{split}\end{equation} \]

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