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

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