There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ \frac{({x}^{4})}{4} + {x}^{3}(\frac{5}{3}) + 7x\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{1}{4}x^{4} + \frac{5}{3}x^{3} + 7x\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{1}{4}x^{4} + \frac{5}{3}x^{3} + 7x\right)}{dx}\\=&\frac{1}{4}*4x^{3} + \frac{5}{3}*3x^{2} + 7\\=&x^{3} + 5x^{2} + 7\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( x^{3} + 5x^{2} + 7\right)}{dx}\\=&3x^{2} + 5*2x + 0\\=&3x^{2} + 10x\\ \end{split}\end{equation} \]

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