There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ cos(7{x}^{2} + 20x + 77)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = cos(7x^{2} + 20x + 77)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( cos(7x^{2} + 20x + 77)\right)}{dx}\\=&-sin(7x^{2} + 20x + 77)(7*2x + 20 + 0)\\=&-14xsin(7x^{2} + 20x + 77) - 20sin(7x^{2} + 20x + 77)\\ \end{split}\end{equation} \]

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