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

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