Functional Scheme Qpositive_plus_ind := Induction for Qpositive_plus Sort Prop.

Lemma Qmult_Z_dL :
forall (a : Z) (p : Qpositive),
Qmult (Z_to_Q a) (Qpos (dL p)) =
Qmult (Qmult (Z_to_Q a) (Qpos p)) (Qinv (Qplus (Qpos p) Qone)).