Nuprl Lemma : subtype_rel_b-union-left

∀[A,B:Type].  (A ⊆r (A ⋃ B))


Proof




Definitions occuring in Statement :  b-union: A ⋃ B,  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  subtype_rel: A ⊆r B,  b-union: A ⋃ B,  tunion: ⋃x:A.B[x],  ifthenelse: if b then t else f fi ,  btrue: tt,  pi2: snd(t)
Lemmas referenced :  btrue_wf,  ifthenelse_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  lambdaEquality,  sqequalRule,  imageMemberEquality,  dependent_pairEquality,  lemma_by_obid,  hypothesis,  hypothesisEquality,  thin,  instantiate,  sqequalHypSubstitution,  isectElimination,  universeEquality,  because_Cache,  equalityTransitivity,  equalitySymmetry,  axiomEquality,  isect_memberEquality

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



Date html generated: 2016_05_13-PM-03_57_47
Last ObjectModification: 2015_12_26-AM-10_51_26

Theory : bool_1


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