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

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