There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ sin(4)xcos(x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = xsin(4)cos(x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( xsin(4)cos(x)\right)}{dx}\\=&sin(4)cos(x) + xcos(4)*0cos(x) + xsin(4)*-sin(x)\\=&sin(4)cos(x) - xsin(x)sin(4)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( sin(4)cos(x) - xsin(x)sin(4)\right)}{dx}\\=&cos(4)*0cos(x) + sin(4)*-sin(x) - sin(x)sin(4) - xcos(x)sin(4) - xsin(x)cos(4)*0\\=&-2sin(x)sin(4) - xsin(4)cos(x)\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( -2sin(x)sin(4) - xsin(4)cos(x)\right)}{dx}\\=&-2cos(x)sin(4) - 2sin(x)cos(4)*0 - sin(4)cos(x) - xcos(4)*0cos(x) - xsin(4)*-sin(x)\\=&-3sin(4)cos(x) + xsin(x)sin(4)\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( -3sin(4)cos(x) + xsin(x)sin(4)\right)}{dx}\\=&-3cos(4)*0cos(x) - 3sin(4)*-sin(x) + sin(x)sin(4) + xcos(x)sin(4) + xsin(x)cos(4)*0\\=&4sin(x)sin(4) + xsin(4)cos(x)\\ \end{split}\end{equation} \]

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