Nuprl Lemma : pgeo-join-implies-plsep

∀g:BasicProjectivePlane. ∀a,b,c:Point. ∀s:a ≠ b.  (c ≠ a ∨ b ⇒ (∀l:Line. ((a I l ∧ b I l) ⇒ c ≠ l)))


Proof




Definitions occuring in Statement :  basic-projective-plane: BasicProjectivePlane,  pgeo-join: p ∨ q,  pgeo-psep: a ≠ b,  pgeo-incident: a I b,  pgeo-plsep: a ≠ b,  pgeo-line: Line,  pgeo-point: Point,  all: ∀x:A. B[x],  implies: P ⇒ Q,  and: P ∧ Q
Definitions unfolded in proof :  uimplies: b supposing a,  guard: {T},  or: P ∨ Q,  prop: ℙ,  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B,  basic-projective-plane: BasicProjectivePlane,  member: t ∈ T,  and: P ∧ Q,  implies: P ⇒ Q,  all: ∀x:A. B[x],  false: False,  not: ¬A,  pgeo-leq: a ≡ b
Lemmas referenced :  pgeo-point_wf,  pgeo-psep_wf,  pgeo-plsep_wf,  pgeo-primitives_wf,  projective-plane-structure_wf,  basic-projective-plane_wf,  subtype_rel_transitivity,  basic-projective-plane-subtype,  projective-plane-structure_subtype,  pgeo-incident_wf,  pgeo-line_wf,  pgeo-join_wf,  PL-sep-or,  pgeo-join-to-line-2
Rules used in proof :  independent_isectElimination,  instantiate,  unionElimination,  independent_functionElimination,  productEquality,  sqequalRule,  isectElimination,  setEquality,  lambdaEquality,  applyEquality,  hypothesis,  rename,  setElimination,  hypothesisEquality,  because_Cache,  dependent_functionElimination,  extract_by_obid,  introduction,  cut,  thin,  productElimination,  sqequalHypSubstitution,  lambdaFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution,  voidElimination

Latex:
\mforall{}g:BasicProjectivePlane.  \mforall{}a,b,c:Point.  \mforall{}s:a  \mneq{}  b.
    (c  \mneq{}  a  \mvee{}  b  {}\mRightarrow{}  (\mforall{}l:Line.  ((a  I  l  \mwedge{}  b  I  l)  {}\mRightarrow{}  c  \mneq{}  l)))



Date html generated: 2018_05_22-PM-00_36_39
Last ObjectModification: 2017_11_15-PM-00_53_58

Theory : euclidean!plane!geometry


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