There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ cth(x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( cth(x)\right)}{dx}\\=&(1 - cth^{2}(x))\\=& - cth^{2}(x) + 1\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( - cth^{2}(x) + 1\right)}{dx}\\=& - 2cth(x)(1 - cth^{2}(x)) + 0\\=& - 2cth(x) + 2cth^{3}(x)\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( - 2cth(x) + 2cth^{3}(x)\right)}{dx}\\=& - 2(1 - cth^{2}(x)) + 2*3cth^{2}(x)(1 - cth^{2}(x))\\=&8cth^{2}(x) - 6cth^{4}(x) - 2\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( 8cth^{2}(x) - 6cth^{4}(x) - 2\right)}{dx}\\=&8*2cth(x)(1 - cth^{2}(x)) - 6*4cth^{3}(x)(1 - cth^{2}(x)) + 0\\=&16cth(x) - 40cth^{3}(x) + 24cth^{5}(x)\\ \end{split}\end{equation} \]

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