Nuprl Lemma : geo-lt-implies-gt-strong
∀g:EuclideanPlane. ∀a,b,c,d:Point.  (|cd| < |ab| ⇒ ab > cd)
Proof
Definitions occuring in Statement : 
geo-lt: p < q, 
geo-length: |s|, 
geo-mk-seg: ab, 
euclidean-plane: EuclideanPlane, 
geo-gt: cd > ab, 
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, 
geo-gt: cd > ab, 
squash: ↓T, 
uall: ∀[x:A]. B[x], 
basic-geometry: BasicGeometry, 
euclidean-plane: EuclideanPlane, 
prop: ℙ, 
subtype_rel: A ⊆r B, 
guard: {T}, 
uimplies: b supposing a
Lemmas referenced : 
geo-lt-implies-gt-strong-1, 
geo-lt_wf, 
geo-length_wf, 
geo-mk-seg_wf, 
geo-point_wf, 
euclidean-plane-structure-subtype, 
euclidean-plane-subtype, 
subtype_rel_transitivity, 
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, 
independent_functionElimination, 
hypothesis, 
sqequalRule, 
imageMemberEquality, 
baseClosed, 
universeIsType, 
isectElimination, 
setElimination, 
rename, 
inhabitedIsType, 
applyEquality, 
instantiate, 
independent_isectElimination
Latex:
\mforall{}g:EuclideanPlane.  \mforall{}a,b,c,d:Point.    (|cd|  <  |ab|  {}\mRightarrow{}  ab  >  cd)
Date html generated:
2019_10_16-PM-01_36_39
Last ObjectModification:
2018_12_11-PM-01_27_14
Theory : euclidean!plane!geometry
Home
Index