Nuprl Lemma : geo-lt-implies-point
∀e:EuclideanPlane. ∀a,b,c,d:Point.  (|ab| < |cd| 
⇒ a ≠ b 
⇒ (∃f:Point. (a-b-f ∧ af ≅ cd)))
Proof
Definitions occuring in Statement : 
geo-lt: p < q
, 
geo-length: |s|
, 
geo-mk-seg: ab
, 
euclidean-plane: EuclideanPlane
, 
geo-strict-between: a-b-c
, 
geo-congruent: ab ≅ cd
, 
geo-sep: a ≠ b
, 
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
, 
exists: ∃x:A. B[x]
, 
and: P ∧ Q
, 
basic-geometry: BasicGeometry
, 
cand: A c∧ B
, 
uall: ∀[x:A]. B[x]
, 
uiff: uiff(P;Q)
, 
uimplies: b supposing a
, 
squash: ↓T
, 
prop: ℙ
, 
true: True
, 
basic-geometry-: BasicGeometry-
, 
subtype_rel: A ⊆r B
, 
guard: {T}
, 
euclidean-plane: EuclideanPlane
Lemmas referenced : 
geo-lt-implies-gt-strong-1, 
geo-proper-extend-exists, 
geo-congruent-iff-length, 
geo-add-length-between, 
geo-add-length_wf, 
squash_wf, 
true_wf, 
geo-length-type_wf, 
basic-geometry_wf, 
geo-between-symmetry, 
geo-strict-between-implies-between, 
geo-strict-between_wf, 
geo-congruent_wf, 
geo-sep_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
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation_alt, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
dependent_functionElimination, 
thin, 
hypothesisEquality, 
independent_functionElimination, 
hypothesis, 
productElimination, 
sqequalRule, 
because_Cache, 
rename, 
dependent_pairFormation_alt, 
independent_pairFormation, 
isectElimination, 
independent_isectElimination, 
applyEquality, 
lambdaEquality_alt, 
imageElimination, 
equalityTransitivity, 
equalitySymmetry, 
universeIsType, 
inhabitedIsType, 
natural_numberEquality, 
imageMemberEquality, 
baseClosed, 
productIsType, 
instantiate, 
setElimination
Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a,b,c,d:Point.    (|ab|  <  |cd|  {}\mRightarrow{}  a  \mneq{}  b  {}\mRightarrow{}  (\mexists{}f:Point.  (a-b-f  \mwedge{}  af  \mcong{}  cd)))
Date html generated:
2019_10_16-PM-01_37_01
Last ObjectModification:
2019_08_07-PM-03_17_52
Theory : euclidean!plane!geometry
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