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

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