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

Your problem has not been solved here? Please take a look at the  hot problems ！