There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ 8sin(x) - 8cos(x) + xcos(x) + xsin(x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 8sin(x) - 8cos(x) + xcos(x) + xsin(x)\right)}{dx}\\=&8cos(x) - 8*-sin(x) + cos(x) + x*-sin(x) + sin(x) + xcos(x)\\=&9cos(x) + 9sin(x) - xsin(x) + xcos(x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 9cos(x) + 9sin(x) - xsin(x) + xcos(x)\right)}{dx}\\=&9*-sin(x) + 9cos(x) - sin(x) - xcos(x) + cos(x) + x*-sin(x)\\=&-10sin(x) + 10cos(x) - xcos(x) - xsin(x)\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( -10sin(x) + 10cos(x) - xcos(x) - xsin(x)\right)}{dx}\\=&-10cos(x) + 10*-sin(x) - cos(x) - x*-sin(x) - sin(x) - xcos(x)\\=&-11cos(x) - 11sin(x) + xsin(x) - xcos(x)\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( -11cos(x) - 11sin(x) + xsin(x) - xcos(x)\right)}{dx}\\=&-11*-sin(x) - 11cos(x) + sin(x) + xcos(x) - cos(x) - x*-sin(x)\\=&12sin(x) - 12cos(x) + xcos(x) + xsin(x)\\ \end{split}\end{equation} \]

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