There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ cos(\frac{πx}{6})\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = cos(\frac{1}{6}πx)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( cos(\frac{1}{6}πx)\right)}{dx}\\=&-sin(\frac{1}{6}πx)*\frac{1}{6}π\\=&\frac{-πsin(\frac{1}{6}πx)}{6}\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( \frac{-πsin(\frac{1}{6}πx)}{6}\right)}{dx}\\=&\frac{-πcos(\frac{1}{6}πx)*\frac{1}{6}π}{6}\\=&\frac{-π^{2}cos(\frac{1}{6}πx)}{36}\\ \end{split}\end{equation} \]

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