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

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