Nuprl Lemma : geo-add-length-lt-sep2
∀e:BasicGeometry. ∀a,b,c,d,g,h:Point.  (|ab| < |cd| + |gh| ⇒ |ab| ≠ |cd| + |gh|)
Proof
Definitions occuring in Statement : 
geo-lt: p < q, 
geo-add-length: p + q, 
geo-length: |s|, 
geo-mk-seg: ab, 
basic-geometry: BasicGeometry, 
geo-sep: a ≠ b, 
geo-point: Point, 
all: ∀x:A. B[x], 
implies: P ⇒ Q
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
member: t ∈ T, 
basic-geometry: BasicGeometry, 
uall: ∀[x:A]. B[x], 
euclidean-plane: EuclideanPlane, 
iff: P ⇐⇒ Q, 
and: P ∧ Q, 
prop: ℙ, 
subtype_rel: A ⊆r B, 
guard: {T}, 
uimplies: b supposing a
Lemmas referenced : 
geo-lt-iff-strict-between-points, 
geo-length_wf1, 
geo-mk-seg_wf, 
geo-add-length_wf1, 
geo-lt_wf, 
geo-length_wf, 
geo-add-length_wf, 
geo-point_wf, 
euclidean-plane-structure-subtype, 
euclidean-plane-subtype, 
basic-geometry-subtype, 
subtype_rel_transitivity, 
basic-geometry_wf, 
euclidean-plane_wf, 
euclidean-plane-structure_wf, 
geo-primitives_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation_alt, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
dependent_functionElimination, 
thin, 
hypothesisEquality, 
isectElimination, 
setElimination, 
rename, 
because_Cache, 
hypothesis, 
productElimination, 
independent_functionElimination, 
universeIsType, 
inhabitedIsType, 
applyEquality, 
instantiate, 
independent_isectElimination, 
sqequalRule
Latex:
\mforall{}e:BasicGeometry.  \mforall{}a,b,c,d,g,h:Point.    (|ab|  <  |cd|  +  |gh|  {}\mRightarrow{}  |ab|  \mneq{}  |cd|  +  |gh|)
Date html generated:
2019_10_16-PM-01_38_45
Last ObjectModification:
2019_02_27-PM-03_44_55
Theory : euclidean!plane!geometry
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