There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -40{x}^{3} + 79{x}^{2}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = -40x^{3} + 79x^{2}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( -40x^{3} + 79x^{2}\right)}{dx}\\=&-40*3x^{2} + 79*2x\\=&-120x^{2} + 158x\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -120x^{2} + 158x\right)}{dx}\\=&-120*2x + 158\\=&-240x + 158\\ \end{split}\end{equation} \]

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