Nuprl Lemma : geo-perp-unicity

∀e:BasicGeometry. ∀a,b,c,u,v:Point.  (a ≠ b ⇒ Colinear(a;b;u) ⇒ Colinear(a;b;v) ⇒ ab ⊥ cu ⇒ ab ⊥ cv ⇒ u ≡ v)


Proof




Definitions occuring in Statement :  geo-perp: ab ⊥ cd,  basic-geometry: BasicGeometry,  geo-colinear: Colinear(a;b;c),  geo-eq: a ≡ b,  geo-sep: a ≠ b,  geo-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,  prop: ℙ,  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B,  guard: {T},  uimplies: b supposing a,  stable: Stable{P},  not: ¬A,  or: P ∨ Q,  false: False,  geo-perp: ab ⊥ cd,  exists: ∃x:A. B[x],  geo-perp-in: ab  ⊥x cd,  and: P ∧ Q,  cand: A c∧ B,  basic-geometry: BasicGeometry,  geo-colinear-set: geo-colinear-set(e; L),  l_all: (∀x∈L.P[x]),  top: Top,  int_seg: {i..j-},  lelt: i ≤ j < k,  le: A ≤ B,  less_than': less_than'(a;b),  less_than: a < b,  squash: ↓T,  true: True,  select: L[n],  cons: [a / b],  subtract: n - m,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  euclidean-plane: EuclideanPlane,  basic-geometry-: BasicGeometry-,  geo-eq: a ≡ b
Lemmas referenced :  geo-perp_wf,  geo-colinear_wf,  euclidean-plane-structure-subtype,  euclidean-plane-subtype,  basic-geometry-subtype,  subtype_rel_transitivity,  basic-geometry_wf,  euclidean-plane_wf,  euclidean-plane-structure_wf,  geo-primitives_wf,  geo-sep_wf,  geo-point_wf,  stable_geo-eq,  false_wf,  or_wf,  not_wf,  geo-eq_wf,  minimal-double-negation-hyp-elim,  minimal-not-not-excluded-middle,  geo-colinear-same,  right-angle-legs-same,  geo-colinear-is-colinear-set,  length_of_cons_lemma,  length_of_nil_lemma,  lelt_wf,  right-angle_functionality,  geo-eq_weakening,  geo-eq_inversion,  geo-perp-trivial-when-colinear,  geo-sep-sym,  geo-eq_transitivity,  subtype_rel_self,  basic-geometry-_wf,  stable__not,  right-angle-symmetry,  geo-colinear_functionality,  geo-sep_functionality,  geo-perp-in-unicity2,  right-angles-not-complementary
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  hypothesis,  applyEquality,  instantiate,  independent_isectElimination,  sqequalRule,  because_Cache,  functionEquality,  independent_functionElimination,  unionElimination,  voidElimination,  productElimination,  dependent_functionElimination,  independent_pairFormation,  isect_memberEquality,  voidEquality,  dependent_set_memberEquality,  natural_numberEquality,  imageMemberEquality,  baseClosed,  promote_hyp,  addLevel,  impliesFunctionality,  levelHypothesis,  impliesLevelFunctionality

Latex:
\mforall{}e:BasicGeometry.  \mforall{}a,b,c,u,v:Point.
    (a  \mneq{}  b  {}\mRightarrow{}  Colinear(a;b;u)  {}\mRightarrow{}  Colinear(a;b;v)  {}\mRightarrow{}  ab  \mbot{}  cu  {}\mRightarrow{}  ab  \mbot{}  cv  {}\mRightarrow{}  u  \mequiv{}  v)



Date html generated: 2018_05_22-PM-00_05_54
Last ObjectModification: 2018_04_19-AM-01_14_59

Theory : euclidean!plane!geometry


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