There are 1 questions in this calculation: for each question, the 15 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ 15th\ derivative\ of\ function\ x*2 + x*6x*56x + 2x*6xx*6 + xx*6x - xxxx*4 - xx - 4x\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = - 4x^{4} + 414x^{3} - x^{2} - 2x\\\\ &\color{blue}{The\ 15th\ derivative\ of\ function:} \\=& - 0\\ \end{split}\end{equation} \]

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