Nuprl Lemma : extended-out-preserves-between
∀e:EuclideanPlane. ∀a,b,c,d:Point.  ((out(a bc) ∧ b-a-d) ⇒ c-a-d)
Proof
Definitions occuring in Statement : 
geo-out: out(p ab), 
euclidean-plane: EuclideanPlane, 
geo-strict-between: a-b-c, 
geo-point: Point, 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
and: P ∧ Q
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
and: P ∧ Q, 
member: t ∈ T, 
uall: ∀[x:A]. B[x], 
basic-geometry: BasicGeometry, 
prop: ℙ, 
subtype_rel: A ⊆r B, 
guard: {T}, 
uimplies: b supposing a, 
geo-out: out(p ab), 
exists: ∃x:A. B[x], 
basic-geometry-: BasicGeometry-, 
iff: P ⇐⇒ Q, 
uiff: uiff(P;Q), 
rev_implies: P ⇐ Q
Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a,b,c,d:Point.    ((out(a  bc)  \mwedge{}  b-a-d)  {}\mRightarrow{}  c-a-d)
Date html generated:
2020_05_20-AM-09_55_47
Last ObjectModification:
2020_01_13-PM-03_29_18
Theory : euclidean!plane!geometry
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