There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ {cos(x)}^{3}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = cos^{3}(x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( cos^{3}(x)\right)}{dx}\\=&-3cos^{2}(x)sin(x)\\=&-3sin(x)cos^{2}(x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -3sin(x)cos^{2}(x)\right)}{dx}\\=&-3cos(x)cos^{2}(x) - 3sin(x)*-2cos(x)sin(x)\\=&-3cos^{3}(x) + 6sin^{2}(x)cos(x)\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( -3cos^{3}(x) + 6sin^{2}(x)cos(x)\right)}{dx}\\=&-3*-3cos^{2}(x)sin(x) + 6*2sin(x)cos(x)cos(x) + 6sin^{2}(x)*-sin(x)\\=&21sin(x)cos^{2}(x) - 6sin^{3}(x)\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( 21sin(x)cos^{2}(x) - 6sin^{3}(x)\right)}{dx}\\=&21cos(x)cos^{2}(x) + 21sin(x)*-2cos(x)sin(x) - 6*3sin^{2}(x)cos(x)\\=&21cos^{3}(x) - 60sin^{2}(x)cos(x)\\ \end{split}\end{equation} \]

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