There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ x(acos(2x) + bsin(2x))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = axcos(2x) + bxsin(2x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( axcos(2x) + bxsin(2x)\right)}{dx}\\=&acos(2x) + ax*-sin(2x)*2 + bsin(2x) + bxcos(2x)*2\\=&acos(2x) - 2axsin(2x) + bsin(2x) + 2bxcos(2x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( acos(2x) - 2axsin(2x) + bsin(2x) + 2bxcos(2x)\right)}{dx}\\=&a*-sin(2x)*2 - 2asin(2x) - 2axcos(2x)*2 + bcos(2x)*2 + 2bcos(2x) + 2bx*-sin(2x)*2\\=&-4asin(2x) - 4axcos(2x) + 4bcos(2x) - 4bxsin(2x)\\ \end{split}\end{equation} \]

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