There are 1 questions in this calculation: for each question, the 4 derivative of o is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ tan(tanh(sin(sinh(\frac{1}{x}))cos(sinh(sin(x)))))\ with\ respect\ to\ o：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( tan(tanh(sin(sinh(\frac{1}{x}))cos(sinh(sin(x)))))\right)}{do}\\=&sec^{2}(tanh(sin(sinh(\frac{1}{x}))cos(sinh(sin(x)))))(sech^{2}(sin(sinh(\frac{1}{x}))cos(sinh(sin(x))))(cos(sinh(\frac{1}{x}))cosh(\frac{1}{x})*0cos(sinh(sin(x))) + sin(sinh(\frac{1}{x}))*-sin(sinh(sin(x)))cosh(sin(x))cos(x)*0))\\=&0\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 0\right)}{do}\\=&0\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( 0\right)}{do}\\=&0\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( 0\right)}{do}\\=&0\\ \end{split}\end{equation} \]

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