There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ 3cos({x}^{4})\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 3cos(x^{4})\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 3cos(x^{4})\right)}{dx}\\=&3*-sin(x^{4})*4x^{3}\\=&-12x^{3}sin(x^{4})\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -12x^{3}sin(x^{4})\right)}{dx}\\=&-12*3x^{2}sin(x^{4}) - 12x^{3}cos(x^{4})*4x^{3}\\=&-36x^{2}sin(x^{4}) - 48x^{6}cos(x^{4})\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( -36x^{2}sin(x^{4}) - 48x^{6}cos(x^{4})\right)}{dx}\\=&-36*2xsin(x^{4}) - 36x^{2}cos(x^{4})*4x^{3} - 48*6x^{5}cos(x^{4}) - 48x^{6}*-sin(x^{4})*4x^{3}\\=&-72xsin(x^{4}) - 432x^{5}cos(x^{4}) + 192x^{9}sin(x^{4})\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( -72xsin(x^{4}) - 432x^{5}cos(x^{4}) + 192x^{9}sin(x^{4})\right)}{dx}\\=&-72sin(x^{4}) - 72xcos(x^{4})*4x^{3} - 432*5x^{4}cos(x^{4}) - 432x^{5}*-sin(x^{4})*4x^{3} + 192*9x^{8}sin(x^{4}) + 192x^{9}cos(x^{4})*4x^{3}\\=&-72sin(x^{4}) - 2448x^{4}cos(x^{4}) + 3456x^{8}sin(x^{4}) + 768x^{12}cos(x^{4})\\ \end{split}\end{equation} \]

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