Nuprl Lemma : Euclid-erect-perp-on-same-side

∀e:EuclideanPlane. ∀a:Point. ∀b:{b:Point| a ≠ b} . ∀c:{c:Point| Colinear(a;b;c)} . ∀q:{q:Point| q # ab} .
  (∃p:Point [(ab  ⊥c pc ∧ p # ab ∧ (p leftof ab ⇐⇒ q leftof ab))])


Proof




Definitions occuring in Statement :  geo-perp-in: ab  ⊥x cd,  euclidean-plane: EuclideanPlane,  geo-lsep: a # bc,  geo-colinear: Colinear(a;b;c),  geo-left: a leftof bc,  geo-sep: a ≠ b,  geo-point: Point,  all: ∀x:A. B[x],  sq_exists: ∃x:A [B[x]],  iff: P ⇐⇒ Q,  and: P ∧ Q,  set: {x:A| B[x]} 
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  euclidean-plane: EuclideanPlane,  sq_stable: SqStable(P),  implies: P ⇒ Q,  squash: ↓T,  exists: ∃x:A. B[x],  sq_exists: ∃x:A [B[x]],  prop: ℙ,  uall: ∀[x:A]. B[x],  subtype_rel: A ⊆r B,  guard: {T},  uimplies: b supposing a,  so_lambda: λ2x.t[x],  so_apply: x[s],  geo-lsep: a # bc,  or: P ∨ Q,  and: P ∧ Q,  cand: A c∧ B,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  basic-geometry: BasicGeometry,  not: ¬A,  false: False
Lemmas referenced :  sq_stable__geo-lsep,  Euclid-erect-2perp,  set_wf,  geo-point_wf,  euclidean-plane-structure-subtype,  euclidean-plane-subtype,  subtype_rel_transitivity,  euclidean-plane_wf,  euclidean-plane-structure_wf,  geo-primitives_wf,  geo-lsep_wf,  geo-colinear_wf,  geo-sep_wf,  lsep-all-sym2,  geo-left_wf,  geo-perp-in_wf,  iff_wf,  not-left-and-right
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  cut,  setElimination,  thin,  rename,  introduction,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  hypothesisEquality,  hypothesis,  because_Cache,  independent_functionElimination,  sqequalRule,  imageMemberEquality,  baseClosed,  imageElimination,  productElimination,  isectElimination,  applyEquality,  instantiate,  independent_isectElimination,  lambdaEquality,  unionElimination,  dependent_set_memberFormation,  independent_pairFormation,  productEquality,  voidElimination

Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a:Point.  \mforall{}b:\{b:Point|  a  \mneq{}  b\}  .  \mforall{}c:\{c:Point|  Colinear(a;b;c)\}  .  \mforall{}q:\{q:Point| 
                                                                                                                                                                          q  \#  ab\}  .
    (\mexists{}p:Point  [(ab    \mbot{}c  pc  \mwedge{}  p  \#  ab  \mwedge{}  (p  leftof  ab  \mLeftarrow{}{}\mRightarrow{}  q  leftof  ab))])



Date html generated: 2018_05_22-PM-00_09_27
Last ObjectModification: 2018_04_04-PM-07_08_08

Theory : euclidean!plane!geometry


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