There are 1 questions in this calculation: for each question, the 4 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 4th\ derivative\ of\ function\ sin(x) + \frac{sin(3x)}{3}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = sin(x) + \frac{1}{3}sin(3x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( sin(x) + \frac{1}{3}sin(3x)\right)}{dx}\\=&cos(x) + \frac{1}{3}cos(3x)*3\\=&cos(x) + cos(3x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( cos(x) + cos(3x)\right)}{dx}\\=&-sin(x) + -sin(3x)*3\\=&-sin(x) - 3sin(3x)\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( -sin(x) - 3sin(3x)\right)}{dx}\\=&-cos(x) - 3cos(3x)*3\\=&-cos(x) - 9cos(3x)\\\\ &\color{blue}{The\ 4th\ derivative\ of\ function:} \\&\frac{d\left( -cos(x) - 9cos(3x)\right)}{dx}\\=&--sin(x) - 9*-sin(3x)*3\\=&sin(x) + 27sin(3x)\\ \end{split}\end{equation} \]

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