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

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