Nuprl Lemma : geo-colinear-left-out3
∀e:EuclideanPlane. ∀a,b,c,a',c',x,x':Point.
  (Colinear(b;x;x') ⇒ a-x-c ⇒ a'-x'-c' ⇒ out(b aa') ⇒ out(b cc') ⇒ b leftof ac ⇒ b leftof a'c' ⇒ out(b xx'))
Proof
Definitions occuring in Statement : 
geo-out: out(p ab), 
euclidean-plane: EuclideanPlane, 
geo-colinear: Colinear(a;b;c), 
geo-strict-between: a-b-c, 
geo-left: a leftof bc, 
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, 
subtype_rel: A ⊆r B, 
uall: ∀[x:A]. B[x], 
guard: {T}, 
uimplies: b supposing a, 
basic-geometry-: BasicGeometry-, 
geo-out: out(p ab), 
and: P ∧ Q, 
cand: A c∧ B, 
not: ¬A, 
geo-eq: a ≡ b, 
prop: ℙ, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q, 
false: False, 
basic-geometry: BasicGeometry, 
geo-strict-between: a-b-c, 
geo-sep: a # b, 
subtract: n - m, 
cons: [a / b], 
select: L[n], 
true: True, 
squash: ↓T, 
less_than: a < b, 
less_than': less_than'(a;b), 
le: A ≤ B, 
lelt: i ≤ j < k, 
int_seg: {i..j-}, 
top: Top, 
l_all: (∀x∈L.P[x]), 
geo-colinear-set: geo-colinear-set(e; L)
Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a,b,c,a',c',x,x':Point.
    (Colinear(b;x;x')
    {}\mRightarrow{}  a-x-c
    {}\mRightarrow{}  a'-x'-c'
    {}\mRightarrow{}  out(b  aa')
    {}\mRightarrow{}  out(b  cc')
    {}\mRightarrow{}  b  leftof  ac
    {}\mRightarrow{}  b  leftof  a'c'
    {}\mRightarrow{}  out(b  xx'))
Date html generated:
2020_05_20-AM-09_59_23
Last ObjectModification:
2020_01_13-PM-03_43_57
Theory : euclidean!plane!geometry
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