There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ -(\frac{2}{3})xx - \frac{9x}{2} + 6\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = \frac{-2}{3}x^{2} - \frac{9}{2}x + 6\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( \frac{-2}{3}x^{2} - \frac{9}{2}x + 6\right)}{dx}\\=&\frac{-2}{3}*2x - \frac{9}{2} + 0\\=&\frac{-4x}{3} - \frac{9}{2}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-4x}{3} - \frac{9}{2}\right)}{dx}\\=&\frac{-4}{3} + 0\\=&\frac{-4}{3}\\ \end{split}\end{equation} \]

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