Nuprl Lemma : not-col-distincts

e:BasicGeometry. ∀A,B,C:Point.  ((¬Colinear(A;B;C))  (¬¬(A ≠ B ∧ B ≠ C ∧ A ≠ C)))


Proof




Definitions occuring in Statement :  basic-geometry: BasicGeometry geo-colinear: Colinear(a;b;c) geo-sep: a ≠ b geo-point: Point all: x:A. B[x] not: ¬A implies:  Q and: P ∧ Q
Definitions unfolded in proof :  rev_implies:  Q iff: ⇐⇒ Q geo-eq: a ≡ b or: P ∨ Q stable: Stable{P} cand: c∧ B basic-geometry: BasicGeometry uimplies: supposing a guard: {T} subtype_rel: A ⊆B and: P ∧ Q uall: [x:A]. B[x] prop: member: t ∈ T false: False not: ¬A implies:  Q all: x:A. B[x]
Lemmas referenced :  minimal-not-not-excluded-middle geo-colinear_functionality geo-eq_weakening geo-sep_functionality minimal-double-negation-hyp-elim geo-colinear-same or_wf false_wf stable__false geo-point_wf geo-colinear_wf Error :basic-geo-primitives_wf,  Error :basic-geo-structure_wf,  basic-geometry_wf subtype_rel_transitivity basic-geometry-subtype geo-sep_wf not_wf
Rules used in proof :  impliesLevelFunctionality promote_hyp levelHypothesis andLevelFunctionality dependent_functionElimination impliesFunctionality addLevel unionElimination productElimination independent_pairFormation functionEquality rename setElimination sqequalRule independent_isectElimination instantiate applyEquality hypothesisEquality productEquality isectElimination extract_by_obid introduction voidElimination independent_functionElimination sqequalHypSubstitution hypothesis because_Cache thin cut lambdaFormation sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution

Latex:
\mforall{}e:BasicGeometry.  \mforall{}A,B,C:Point.    ((\mneg{}Colinear(A;B;C))  {}\mRightarrow{}  (\mneg{}\mneg{}(A  \mneq{}  B  \mwedge{}  B  \mneq{}  C  \mwedge{}  A  \mneq{}  C)))



Date html generated: 2017_10_02-PM-06_32_12
Last ObjectModification: 2017_08_05-PM-04_43_01

Theory : euclidean!plane!geometry


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