There are 1 questions in this calculation: for each question, the 3 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ third\ derivative\ of\ function\ -x + 3{x}^{4}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -x + 3x^{4}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -x + 3x^{4}\right)}{dx}\\=&-1 + 3*4x^{3}\\=&12x^{3} - 1\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 12x^{3} - 1\right)}{dx}\\=&12*3x^{2} + 0\\=&36x^{2}\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( 36x^{2}\right)}{dx}\\=&36*2x\\=&72x\\ \end{split}\end{equation} \]

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