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

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