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

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