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

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