There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ cos(93{x}^{2} + 84x + 81)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = cos(93x^{2} + 84x + 81)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( cos(93x^{2} + 84x + 81)\right)}{dx}\\=&-sin(93x^{2} + 84x + 81)(93*2x + 84 + 0)\\=&-186xsin(93x^{2} + 84x + 81) - 84sin(93x^{2} + 84x + 81)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -186xsin(93x^{2} + 84x + 81) - 84sin(93x^{2} + 84x + 81)\right)}{dx}\\=&-186sin(93x^{2} + 84x + 81) - 186xcos(93x^{2} + 84x + 81)(93*2x + 84 + 0) - 84cos(93x^{2} + 84x + 81)(93*2x + 84 + 0)\\=&-186sin(93x^{2} + 84x + 81) - 34596x^{2}cos(93x^{2} + 84x + 81) - 31248xcos(93x^{2} + 84x + 81) - 7056cos(93x^{2} + 84x + 81)\\ \end{split}\end{equation} \]

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