There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ {x}^{9} - 9{x}^{8}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = x^{9} - 9x^{8}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( x^{9} - 9x^{8}\right)}{dx}\\=&9x^{8} - 9*8x^{7}\\=&9x^{8} - 72x^{7}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 9x^{8} - 72x^{7}\right)}{dx}\\=&9*8x^{7} - 72*7x^{6}\\=&72x^{7} - 504x^{6}\\ \end{split}\end{equation} \]

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