There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ sin(12x) - cos(6x)\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( sin(12x) - cos(6x)\right)}{dx}\\=&cos(12x)*12 - -sin(6x)*6\\=&12cos(12x) + 6sin(6x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( 12cos(12x) + 6sin(6x)\right)}{dx}\\=&12*-sin(12x)*12 + 6cos(6x)*6\\=&-144sin(12x) + 36cos(6x)\\ \end{split}\end{equation} \]

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