Nuprl Lemma : tarski-erect-perp1

∀e:HeytingGeometry. ∀a,b,c:Point.  (c # ba ⇒ (∃p,t,d:Point. ((ab ⊥ pa ∧ Colinear(a;b;t)) ∧ p-t-d)))


Proof




Definitions occuring in Statement :  geo-triangle: a # bc,  heyting-geometry: HeytingGeometry,  geo-perp: ab ⊥ cd,  geo-colinear: Colinear(a;b;c),  geo-strict-between: a-b-c,  geo-point: Point,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  and: P ∧ Q
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  guard: {T},  and: P ∧ Q,  cand: A c∧ B,  exists: ∃x:A. B[x],  geo-perp-in: ab  ⊥x cd,  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B,  heyting-geometry: HeytingGeometry,  euclidean-plane: EuclideanPlane,  basic-geometry: BasicGeometry,  prop: ℙ,  uimplies: b supposing a,  geo-triangle: a # bc,  oriented-plane: OrientedPlane,  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),  false: False,  not: ¬A,  less_than: a < b,  squash: ↓T,  true: True,  select: L[n],  cons: [a / b],  subtract: n - m,  or: P ∨ Q,  right-angle: Rabc,  geo-midpoint: a=m=b,  basic-geometry-: BasicGeometry-,  uiff: uiff(P;Q),  geo-strict-between: a-b-c,  so_lambda: λ2x.t[x],  so_apply: x[s],  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  geo-perp: ab ⊥ cd,  append: as @ bs,  so_lambda: so_lambda(x,y,z.t[x; y; z]),  so_apply: x[s1;s2;s3]
Lemmas referenced :  tarski-perp-in-exists,  geo-triangle-symmetry,  geo-colinear-same,  subtype_rel_self,  euclidean-plane-structure_wf,  basic-geo-axioms_wf,  euclidean-plane-structure-subtype,  geo-left-axioms_wf,  geo-triangle_wf,  euclidean-plane-subtype,  heyting-geometry-subtype,  subtype_rel_transitivity,  heyting-geometry_wf,  euclidean-plane_wf,  geo-primitives_wf,  geo-point_wf,  geo-proper-extend-exists,  lsep-colinear-sep,  geo-colinear-is-colinear-set,  length_of_cons_lemma,  length_of_nil_lemma,  false_wf,  lelt_wf,  geo-sep-or,  geo-sep-sym,  geo-triangle-property,  geo-sep_wf,  geo-strict-between-implies-between,  geo-between-symmetry,  geo-congruent-iff-length,  geo-length-flip,  geo-triangle-colinear,  geo-strict-between-sep1,  geo-strict-between-implies-colinear,  geo-triangle-colinear2,  geo-strict-between-sep3,  geo-congruent-mid-exists,  geo-perp-midsegments,  midpoint-sep,  geo-between-implies-colinear,  double-pasch-exists,  geo-strict-between-sym,  exists_wf,  geo-perp_wf,  geo-colinear_wf,  geo-strict-between_wf,  geo-perp-in-iff,  right-angle_wf,  geo-perp-in_wf,  oriented-colinear-append,  cons_wf,  nil_wf,  cons_member,  l_member_wf,  equal_wf,  list_ind_cons_lemma,  list_ind_nil_lemma,  geo-midpoint-diagonals-between,  symmetry-preserves-congruence,  geo-congruent-symmetry,  geo-congruent-sep,  perp-aux2,  right-angle-colinear,  right-angle-symmetry,  geo-midpoint-symmetry,  colinear-implies-midpoint
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  independent_functionElimination,  because_Cache,  hypothesis,  productElimination,  isectElimination,  applyEquality,  sqequalRule,  instantiate,  setEquality,  productEquality,  cumulativity,  independent_isectElimination,  rename,  isect_memberEquality,  voidElimination,  voidEquality,  dependent_set_memberEquality,  natural_numberEquality,  independent_pairFormation,  imageMemberEquality,  baseClosed,  setElimination,  unionElimination,  equalityTransitivity,  equalitySymmetry,  dependent_pairFormation,  lambdaEquality,  universeEquality,  inrFormation,  inlFormation

Latex:
\mforall{}e:HeytingGeometry.  \mforall{}a,b,c:Point.    (c  \#  ba  {}\mRightarrow{}  (\mexists{}p,t,d:Point.  ((ab  \mbot{}  pa  \mwedge{}  Colinear(a;b;t))  \mwedge{}  p-t-d)))



Date html generated: 2017_10_02-PM-07_10_33
Last ObjectModification: 2017_08_10-PM-03_38_32

Theory : euclidean!plane!geometry


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