There are 1 questions in this calculation: for each question, the 3 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ third\ derivative\ of\ function\ x - \frac{{x}^{3}}{6}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = x - \frac{1}{6}x^{3}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( x - \frac{1}{6}x^{3}\right)}{dx}\\=&1 - \frac{1}{6}*3x^{2}\\=& - \frac{x^{2}}{2} + 1\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( - \frac{x^{2}}{2} + 1\right)}{dx}\\=& - \frac{2x}{2} + 0\\=& - x\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( - x\right)}{dx}\\=& - 1\\ \end{split}\end{equation} \]

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