There are 1 questions in this calculation: for each question, the 3 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ third\ derivative\ of\ function\ arccos(a)x\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = xarccos(a)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( xarccos(a)\right)}{dx}\\=&arccos(a) + x(\frac{-(0)}{((1 - (a)^{2})^{\frac{1}{2}})})\\=&arccos(a)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( arccos(a)\right)}{dx}\\=&(\frac{-(0)}{((1 - (a)^{2})^{\frac{1}{2}})})\\=&0\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( 0\right)}{dx}\\=&0\\ \end{split}\end{equation} \]

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