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

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