[Boost-users] Questions about Boost.Multiprecision..

I want to be performing some algebraic functions work on cpp_rational which I will be using templates with the following type to configure precision (and scale?) #include in order to avoid the use of floating point types. --What is the #include statement for cpp_rational? I can't manage to find it. -When using non-floating point, is there a method to obtain a variable precision pi, or do I have to use arccos(-1); ? What is the file to import for that? -If I want to import a non-floating-point (cpp_rational) library power, nth root, trigonometry, all the useful function, what is the #include and the file in boost for that?