There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ cos(78{x}^{2} + 58x - 86)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = cos(78x^{2} + 58x - 86)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( cos(78x^{2} + 58x - 86)\right)}{dx}\\=&-sin(78x^{2} + 58x - 86)(78*2x + 58 + 0)\\=&-156xsin(78x^{2} + 58x - 86) - 58sin(78x^{2} + 58x - 86)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( -156xsin(78x^{2} + 58x - 86) - 58sin(78x^{2} + 58x - 86)\right)}{dx}\\=&-156sin(78x^{2} + 58x - 86) - 156xcos(78x^{2} + 58x - 86)(78*2x + 58 + 0) - 58cos(78x^{2} + 58x - 86)(78*2x + 58 + 0)\\=&-156sin(78x^{2} + 58x - 86) - 24336x^{2}cos(78x^{2} + 58x - 86) - 18096xcos(78x^{2} + 58x - 86) - 3364cos(78x^{2} + 58x - 86)\\ \end{split}\end{equation} \]

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