proposition: Lemma FSum_minus_FSum : forall (f g : nat -> PartIR) m n x Hx HxF HxG, FSum m n (fun i => f i{-}g i) x Hx [=] FSum m n f x HxF[-]FSum m n g x HxG.
proof: Proof. intros. simpl in |- *. eapply eq_transitive_unfolded. 2: apply Sum_minus_Sum. apply Sum_wd; intros; rational. Qed.
imports: CoRN.reals.CSumsReals CoRN.ftc.PartFunEquality