There are 1 questions in this calculation: for each question, the 2 derivative of x is calculated.
    Note that variables are case sensitive.
\[ \begin{equation}\begin{split}[1/1]Find\ the\ second\ derivative\ of\ function\ x(arccos(x) + bsin(x))\ with\ respect\ to\ x：\\\end{split}\end{equation} \]\[ \begin{equation}\begin{split}\\Solution:&\\ &Primitive\ function\ = xarccos(x) + bxsin(x)\\&\color{blue}{The\ first\ derivative\ function：}\\&\frac{d\left( xarccos(x) + bxsin(x)\right)}{dx}\\=&arccos(x) + x(\frac{-(1)}{((1 - (x)^{2})^{\frac{1}{2}})}) + bsin(x) + bxcos(x)\\=&arccos(x) - \frac{x}{(-x^{2} + 1)^{\frac{1}{2}}} + bsin(x) + bxcos(x)\\\\ &\color{blue}{The\ second\ derivative\ of\ function:} \\&\frac{d\left( arccos(x) - \frac{x}{(-x^{2} + 1)^{\frac{1}{2}}} + bsin(x) + bxcos(x)\right)}{dx}\\=&(\frac{-(1)}{((1 - (x)^{2})^{\frac{1}{2}})}) - (\frac{\frac{-1}{2}(-2x + 0)}{(-x^{2} + 1)^{\frac{3}{2}}})x - \frac{1}{(-x^{2} + 1)^{\frac{1}{2}}} + bcos(x) + bcos(x) + bx*-sin(x)\\=& - \frac{x^{2}}{(-x^{2} + 1)^{\frac{3}{2}}} - \frac{1}{(-x^{2} + 1)^{\frac{1}{2}}} - \frac{1}{(-x^{2} + 1)^{\frac{1}{2}}} + 2bcos(x) - bxsin(x)\\ \end{split}\end{equation} \]

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