Nuprl Lemma : subtype_rel_b-union_iff

∀[A,B,C:Type].  uiff((B ⋃ C) ⊆r A;(B ⊆r A) ∧ (C ⊆r A))


Proof




Definitions occuring in Statement :  b-union: A ⋃ B,  uiff: uiff(P;Q),  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  and: P ∧ Q,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  guard: {T},  subtype_rel: A ⊆r B,  prop: ℙ,  b-union: A ⋃ B,  tunion: ⋃x:A.B[x],  bool: 𝔹,  unit: Unit,  ifthenelse: if b then t else f fi ,  pi2: snd(t)
Lemmas referenced :  subtype_rel_b-union-left,  subtype_rel_transitivity,  b-union_wf,  subtype_rel_b-union-right,  subtype_rel_wf,  and_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  independent_pairFormation,  sqequalHypSubstitution,  lemma_by_obid,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  because_Cache,  independent_isectElimination,  sqequalRule,  productElimination,  independent_pairEquality,  axiomEquality,  isect_memberEquality,  equalityTransitivity,  equalitySymmetry,  universeEquality,  lambdaEquality,  imageElimination,  unionElimination,  equalityElimination,  applyEquality

Latex:
\mforall{}[A,B,C:Type].    uiff((B  \mcup{}  C)  \msubseteq{}r  A;(B  \msubseteq{}r  A)  \mwedge{}  (C  \msubseteq{}r  A))



Date html generated: 2016_05_13-PM-03_57_54
Last ObjectModification: 2015_12_26-AM-10_52_04

Theory : bool_1


Home Index