Hi
I have quite complex trigonometric function to solve, but sage only solves sin(alpha) and leaves some cos(alpha) on the other side. It is hard to explain, but see the link below: http://sage.ehasa.org:8080/home/pub/2/
(It would be also nice to generate dynamic function where I put v, x and y. Tried something but I wasn't able to do that, help please?)