Nuprl Lemma : double_isect_subtype_rel

∀[T1,T2:Type]. ∀[B:T1 ⟶ T2 ⟶ Type]. ∀[x:T1]. ∀[y:T2].  ((⋂x:T1. ⋂y:T2.  B[x;y]) ⊆r B[x;y])


Proof




Definitions occuring in Statement :  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  so_apply: x[s1;s2],  isect: ⋂x:A. B[x],  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  so_apply: x[s1;s2],  subtype_rel: A ⊆r B,  all: ∀x:A. B[x],  implies: P ⇒ Q,  prop: ℙ
Lemmas referenced :  equal_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation,  introduction,  cut,  sqequalRule,  lambdaEquality,  isectElimination,  hypothesisEquality,  equalityTransitivity,  equalitySymmetry,  hypothesis,  thin,  isectEquality,  cumulativity,  applyEquality,  functionExtensionality,  lambdaFormation,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  independent_functionElimination,  axiomEquality,  isect_memberEquality,  because_Cache,  functionEquality,  universeEquality

Latex:
\mforall{}[T1,T2:Type].  \mforall{}[B:T1  {}\mrightarrow{}  T2  {}\mrightarrow{}  Type].  \mforall{}[x:T1].  \mforall{}[y:T2].    ((\mcap{}x:T1.  \mcap{}y:T2.    B[x;y])  \msubseteq{}r  B[x;y])



Date html generated: 2017_04_14-AM-07_14_04
Last ObjectModification: 2017_02_27-PM-02_49_57

Theory : subtype_0


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