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

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