There are 1 questions in this calculation: for each question, the 1 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ first\ derivative\ of\ function\ 8x - sin(x){\frac{1}{cos(x)}}^{3}\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = 8x - \frac{sin(x)}{cos^{3}(x)}\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( 8x - \frac{sin(x)}{cos^{3}(x)}\right)}{dx}\\=&8 - \frac{cos(x)}{cos^{3}(x)} - \frac{sin(x)*3sin(x)}{cos^{4}(x)}\\=& - \frac{1}{cos^{2}(x)} - \frac{3sin^{2}(x)}{cos^{4}(x)} + 8\\ \end{split}\end{equation} \]

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