There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ x(Csin(x) + Bcos(x))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = Cxsin(x) + Bxcos(x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( Cxsin(x) + Bxcos(x)\right)}{dx}\\=&Csin(x) + Cxcos(x) + Bcos(x) + Bx*-sin(x)\\=&Csin(x) + Cxcos(x) + Bcos(x) - Bxsin(x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( Csin(x) + Cxcos(x) + Bcos(x) - Bxsin(x)\right)}{dx}\\=&Ccos(x) + Ccos(x) + Cx*-sin(x) + B*-sin(x) - Bsin(x) - Bxcos(x)\\=&2Ccos(x) - Cxsin(x) - 2Bsin(x) - Bxcos(x)\\ \end{split}\end{equation} \]

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