fact: Definition div O E E' A B C := exists IB : Tpoint, inv O E E' B IB /\ Prod O E E' A IB C.
imports: Description Ring Field Nsatz Rtauto GeoCoq.Tarski_dev.Ch16_coordinates GeoCoq.Tarski_dev.Ch15_pyth_rel GeoCoq.Tarski_dev.Annexes.midpoint_theorems