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

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