intros; apply floatEq; simpl in |- *; repeat rewrite (Zmin_sym Fexp0 Fexp);
repeat rewrite Zopp_mult_distr_l_reverse; auto with zarith.
Qed.

Theorem Fopp_Fminus_dist :
forall p q : float, Fopp (Fminus p q) = Fminus (Fopp p) (Fopp q).