proposition: Lemma beta_def : xe = (l * cos beta + xi intr 0)%R /\ ye = (yi intr 0 - l * sin beta)%R /\ (0 <= beta + thetat intr 0 < 2 * PI)%R.
proof: Proof. unfold beta in |- *; case beta_exists; trivial. Qed.
imports: Bool Reals trajectory_const rrho trajectory_def constants ycngftys ycngstys Omega