Nuprl Lemma : cong-angle-out-exists-iff
∀e:BasicGeometry. ∀a,b,c,x,y,z:Point.
  ((((b ≠ a ∧ b ≠ c) ∧ y ≠ x) ∧ y ≠ z)
  
⇒ (abc ≅a xyz 
⇐⇒ ∃a',c',x',z':Point. ((((out(b a'a) ∧ out(b c'c)) ∧ out(y x'x)) ∧ out(y z'z)) ∧ a'bc' ≅a x'yz')))
Proof
Definitions occuring in Statement : 
geo-out: out(p ab)
, 
geo-cong-angle: abc ≅a xyz
, 
basic-geometry: BasicGeometry
, 
geo-sep: a ≠ b
, 
geo-point: Point
, 
all: ∀x:A. B[x]
, 
exists: ∃x:A. B[x]
, 
iff: P 
⇐⇒ Q
, 
implies: P 
⇒ Q
, 
and: P ∧ Q
Definitions unfolded in proof : 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
and: P ∧ Q
, 
iff: P 
⇐⇒ Q
, 
member: t ∈ T
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
rev_implies: P 
⇐ Q
, 
exists: ∃x:A. B[x]
, 
subtype_rel: A ⊆r B
, 
guard: {T}
, 
uimplies: b supposing a
, 
basic-geometry: BasicGeometry
, 
cand: A c∧ B
, 
geo-cong-angle: abc ≅a xyz
, 
geo-out: out(p ab)
Lemmas referenced : 
geo-cong-angle_wf, 
geo-out_wf, 
geo-sep_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, 
geo-point_wf, 
cong-angle-out-exists2, 
geo-sep-sym, 
cong-angle-out-aux2_1, 
geo-between-out, 
geo-between-sep, 
geo-out_transitivity, 
geo-out_inversion
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation_alt, 
sqequalHypSubstitution, 
productElimination, 
thin, 
independent_pairFormation, 
universeIsType, 
cut, 
introduction, 
extract_by_obid, 
isectElimination, 
hypothesisEquality, 
hypothesis, 
sqequalRule, 
productIsType, 
inhabitedIsType, 
because_Cache, 
applyEquality, 
instantiate, 
independent_isectElimination, 
dependent_functionElimination, 
independent_functionElimination, 
dependent_pairFormation_alt, 
rename
Latex:
\mforall{}e:BasicGeometry.  \mforall{}a,b,c,x,y,z:Point.
    ((((b  \mneq{}  a  \mwedge{}  b  \mneq{}  c)  \mwedge{}  y  \mneq{}  x)  \mwedge{}  y  \mneq{}  z)
    {}\mRightarrow{}  (abc  \mcong{}\msuba{}  xyz
          \mLeftarrow{}{}\mRightarrow{}  \mexists{}a',c',x',z':Point
                    ((((out(b  a'a)  \mwedge{}  out(b  c'c))  \mwedge{}  out(y  x'x))  \mwedge{}  out(y  z'z))  \mwedge{}  a'bc'  \mcong{}\msuba{}  x'yz')))
Date html generated:
2019_10_16-PM-01_31_27
Last ObjectModification:
2018_11_12-PM-03_55_35
Theory : euclidean!plane!geometry
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