proposition: Theorem homography_algorithm_is_correct : forall (a b c d : Z) (q : Q) (H_denom : Qplus (Qmult c q) d <> Zero), Qhomographic a b c d q (Qhomographic_denom_nonzero_correct_1 c d q H_denom) = Qmult (Qplus (Qmult a q) b) (Qinv (Qplus (Qmult c q) d)).
proof: Proof. intros a b c d q H_denom; apply (homography a b c d q (Qhomographic_denom_nonzero_correct_1 c d q H_denom)). Defined.
imports: Coq(FunInd) QArithSternBrocot(Field_Theory_Q)