Nuprl Lemma : Euclid-drop-perp-1

∀e:EuclideanPlane. ∀a:Point. ∀b:{b:Point| a ≠ b} . ∀c:{c:Point| ∀x:Point. (Colinear(a;b;x) ⇒ c ≠ x)} .
  ∃p:Point. (Colinear(a;b;p) ∧ ab  ⊥p pc)


Proof




Definitions occuring in Statement :  geo-perp-in: ab  ⊥x cd,  euclidean-plane: EuclideanPlane,  geo-colinear: Colinear(a;b;c),  geo-sep: a ≠ b,  geo-point: Point,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  and: P ∧ Q,  set: {x:A| B[x]} 
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  exists: ∃x:A. B[x],  sq_exists: ∃x:A [B[x]],  and: P ∧ Q,  cand: A c∧ B,  subtype_rel: A ⊆r B,  uall: ∀[x:A]. B[x],  guard: {T},  uimplies: b supposing a,  sq_stable: SqStable(P),  implies: P ⇒ Q,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  geo-perp-in: ab  ⊥x cd,  squash: ↓T,  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),  false: False,  not: ¬A,  prop: ℙ,  less_than: a < b,  true: True,  select: L[n],  cons: [a / b],  subtract: n - m,  so_lambda: λ2x.t[x],  so_apply: x[s]
Lemmas referenced :  Euclid-drop-perp-0,  sq_stable__colinear,  euclidean-plane-structure-subtype,  euclidean-plane-subtype,  subtype_rel_transitivity,  euclidean-plane_wf,  euclidean-plane-structure_wf,  geo-primitives_wf,  euclidean-plane-axioms,  sq_stable__from_stable,  geo-perp-in_wf,  stable__geo-perp-in,  geo-perp-in-iff2,  geo-colinear-is-colinear-set,  length_of_cons_lemma,  length_of_nil_lemma,  false_wf,  lelt_wf,  geo-colinear_wf,  geo-point_wf,  all_wf,  geo-sep_wf
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  hypothesis,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  setElimination,  rename,  productElimination,  dependent_pairFormation,  applyEquality,  instantiate,  isectElimination,  independent_isectElimination,  sqequalRule,  independent_functionElimination,  imageMemberEquality,  baseClosed,  imageElimination,  independent_pairFormation,  because_Cache,  isect_memberEquality,  voidElimination,  voidEquality,  dependent_set_memberEquality,  natural_numberEquality,  productEquality,  setEquality,  lambdaEquality,  functionEquality

Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a:Point.  \mforall{}b:\{b:Point|  a  \mneq{}  b\}  .
\mforall{}c:\{c:Point|  \mforall{}x:Point.  (Colinear(a;b;x)  {}\mRightarrow{}  c  \mneq{}  x)\}  .
    \mexists{}p:Point.  (Colinear(a;b;p)  \mwedge{}  ab    \mbot{}p  pc)



Date html generated: 2018_05_22-PM-00_11_58
Last ObjectModification: 2018_05_11-PM-03_22_52

Theory : euclidean!plane!geometry


Home Index