fact: Variables (d z : Qpos) (x y: Q) (B: Qball (proj1_sig d / proj1_sig z) x y).
imports: CoRN.metric2.Metric CoRN.metric2.Prelength CoRN.metric2.Classification CoRN.model.totalorder.QMinMax CoRN.model.totalorder.QposMinMax Coq.QArith.Qabs CoRN.metric2.UniformContinuity MathClasses.implementations.stdlib_rationals