Nuprl Lemma : geo-lt-not-congruent
∀g:EuclideanPlane. ∀a,b,c,d:Point.  (|ab| < |cd| 
⇒ (¬ab ≅ cd))
Proof
Definitions occuring in Statement : 
geo-lt: p < q
, 
geo-length: |s|
, 
geo-mk-seg: ab
, 
euclidean-plane: EuclideanPlane
, 
geo-congruent: ab ≅ cd
, 
geo-point: Point
, 
all: ∀x:A. B[x]
, 
not: ¬A
, 
implies: P 
⇒ Q
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
not: ¬A
, 
false: False
, 
member: t ∈ T
, 
prop: ℙ
, 
uall: ∀[x:A]. B[x]
, 
subtype_rel: A ⊆r B
, 
guard: {T}
, 
uimplies: b supposing a
, 
basic-geometry: BasicGeometry
, 
euclidean-plane: EuclideanPlane
, 
stable: Stable{P}
, 
or: P ∨ Q
, 
geo-eq: a ≡ b
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
geo-lt: p < q
, 
exists: ∃x:A. B[x]
, 
uiff: uiff(P;Q)
, 
true: True
, 
squash: ↓T
, 
rev_implies: P 
⇐ Q
Lemmas referenced : 
geo-congruent_wf, 
euclidean-plane-structure-subtype, 
euclidean-plane-subtype, 
subtype_rel_transitivity, 
euclidean-plane_wf, 
euclidean-plane-structure_wf, 
geo-primitives_wf, 
geo-lt_wf, 
geo-length_wf, 
geo-mk-seg_wf, 
geo-point_wf, 
stable__false, 
false_wf, 
or_wf, 
geo-sep_wf, 
not_wf, 
minimal-double-negation-hyp-elim, 
geo-congruent_functionality, 
geo-eq_weakening, 
minimal-not-not-excluded-middle, 
geo-congruent-iff-length, 
geo-le_wf, 
squash_wf, 
true_wf, 
geo-length-type_wf, 
basic-geometry_wf, 
geo-add-length_wf, 
subtype_rel_self, 
iff_weakening_equal, 
geo-add-length-le-implies-eq, 
geo-zero-lt-iff, 
geo-zero-length-iff, 
geo-eq-self, 
geo-congruence-identity3
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation, 
cut, 
thin, 
because_Cache, 
hypothesis, 
sqequalHypSubstitution, 
independent_functionElimination, 
voidElimination, 
introduction, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
applyEquality, 
instantiate, 
independent_isectElimination, 
sqequalRule, 
setElimination, 
rename, 
functionEquality, 
unionElimination, 
dependent_functionElimination, 
productElimination, 
natural_numberEquality, 
equalityTransitivity, 
equalitySymmetry, 
lambdaEquality, 
imageElimination, 
imageMemberEquality, 
baseClosed, 
universeEquality
Latex:
\mforall{}g:EuclideanPlane.  \mforall{}a,b,c,d:Point.    (|ab|  <  |cd|  {}\mRightarrow{}  (\mneg{}ab  \mcong{}  cd))
Date html generated:
2019_10_16-PM-02_49_42
Last ObjectModification:
2018_09_16-PM-05_13_29
Theory : euclidean!plane!geometry
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