title: How to compute the sine of huge numbers
body: <p>For several days, I've been wondering how it would be possible of computing the sine of huge numbers with magnitude around <code>100000!</code> (radians). The factorial is just an example the number itself can be any not just a factorial product ...) I obviously don't use <code>double</code> but <code>cpp_rational</code> from the boost multiprecision library. But I can't simply do <code>100000! mod 2pi</code> and then use the builtin function <code>sinl</code> (I don't need more than 10 decimal digits..) as I'd need several million digits of pi to do this accurately.</p>
  
  <p>Is there any way to achieve this?</p>