Nuprl Lemma : pgeo-join-plsep-sym

∀pg:ProjectivePlane. ∀a,b,c:Point. ∀s:a ≠ b. ∀s2:b ≠ a.  (c ≠ a ∨ b ⇒ c ≠ b ∨ a)


Proof




Definitions occuring in Statement :  projective-plane: ProjectivePlane,  pgeo-join: p ∨ q,  pgeo-psep: a ≠ b,  pgeo-plsep: a ≠ b,  pgeo-point: Point,  all: ∀x:A. B[x],  implies: P ⇒ Q
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  guard: {T},  uimplies: b supposing a,  and: P ∧ Q,  prop: ℙ,  or: P ∨ Q,  pgeo-lsep: l ≠ m,  exists: ∃x:A. B[x],  pgeo-incident: a I b,  not: ¬A,  false: False
Lemmas referenced :  PL-sep-or,  pgeo-join_wf,  projective-plane-structure-complete_subtype,  projective-plane-subtype,  subtype_rel_transitivity,  projective-plane_wf,  projective-plane-structure-complete_wf,  projective-plane-structure_wf,  pgeo-line_wf,  pgeo-incident_wf,  pgeo-join-lsep-sym,  pgeo-plsep_wf,  projective-plane-structure_subtype,  pgeo-primitives_wf,  pgeo-psep_wf,  pgeo-point_wf
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  because_Cache,  hypothesisEquality,  applyEquality,  hypothesis,  instantiate,  isectElimination,  independent_isectElimination,  sqequalRule,  lambdaEquality,  setElimination,  rename,  setEquality,  productEquality,  independent_functionElimination,  unionElimination,  productElimination,  voidElimination

Latex:
\mforall{}pg:ProjectivePlane.  \mforall{}a,b,c:Point.  \mforall{}s:a  \mneq{}  b.  \mforall{}s2:b  \mneq{}  a.    (c  \mneq{}  a  \mvee{}  b  {}\mRightarrow{}  c  \mneq{}  b  \mvee{}  a)



Date html generated: 2018_05_22-PM-00_49_01
Last ObjectModification: 2017_12_05-AM-11_23_23

Theory : euclidean!plane!geometry


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