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

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