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

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