There are 1 questions in this calculation: for each question, the 3 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ third\ derivative\ of\ function\ (85{x}^{2} + 212x - 260)e^{-3x}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 85x^{2}e^{-3x} + 212xe^{-3x} - 260e^{-3x}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 85x^{2}e^{-3x} + 212xe^{-3x} - 260e^{-3x}\right)}{dx}\\=&85*2xe^{-3x} + 85x^{2}e^{-3x}*-3 + 212e^{-3x} + 212xe^{-3x}*-3 - 260e^{-3x}*-3\\=&-466xe^{-3x} - 255x^{2}e^{-3x} + 992e^{-3x}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -466xe^{-3x} - 255x^{2}e^{-3x} + 992e^{-3x}\right)}{dx}\\=&-466e^{-3x} - 466xe^{-3x}*-3 - 255*2xe^{-3x} - 255x^{2}e^{-3x}*-3 + 992e^{-3x}*-3\\=&-3442e^{-3x} + 888xe^{-3x} + 765x^{2}e^{-3x}\\\\ &\color{blue}{The\ third\ derivative\ of\ function:} \\&\frac{d\left( -3442e^{-3x} + 888xe^{-3x} + 765x^{2}e^{-3x}\right)}{dx}\\=&-3442e^{-3x}*-3 + 888e^{-3x} + 888xe^{-3x}*-3 + 765*2xe^{-3x} + 765x^{2}e^{-3x}*-3\\=&11214e^{-3x} - 1134xe^{-3x} - 2295x^{2}e^{-3x}\\ \end{split}\end{equation} \]

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