There are 2 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/2]Find\ the\ second\ derivative\ of\ function\ 4xx\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 4x^{2}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 4x^{2}\right)}{dx}\\=&4*2x\\=&8x\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 8x\right)}{dx}\\=&8\\ \end{split}\end{equation} \]

\[ \begin{equation}\begin{split}[2/2]Find\ the\ second\ derivative\ of\ function\ 5xxx\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 5x^{3}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 5x^{3}\right)}{dx}\\=&5*3x^{2}\\=&15x^{2}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 15x^{2}\right)}{dx}\\=&15*2x\\=&30x\\ \end{split}\end{equation} \]

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