Nuprl Lemma : geo-parallel-points-symmetry2
∀e:EuclideanPlane. ∀a,b,c,d:Point.
  (geo-parallel-points(e;a;b;c;d)
  
⇒ (geo-parallel-points(e;b;a;c;d) ∧ geo-parallel-points(e;a;b;d;c) ∧ geo-parallel-points(e;b;a;d;c)))
Proof
Definitions occuring in Statement : 
geo-parallel-points: geo-parallel-points(e;a;b;c;d)
, 
euclidean-plane: EuclideanPlane
, 
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
, 
cand: A c∧ B
, 
geo-parallel-points: geo-parallel-points(e;a;b;c;d)
, 
member: t ∈ T
, 
not: ¬A
, 
exists: ∃x:A. B[x]
, 
false: False
, 
uall: ∀[x:A]. B[x]
, 
subtype_rel: A ⊆r B
, 
prop: ℙ
, 
guard: {T}
, 
uimplies: b supposing a
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
geo-colinear-set: geo-colinear-set(e; L)
, 
l_all: (∀x∈L.P[x])
, 
top: Top
, 
int_seg: {i..j-}
, 
lelt: i ≤ j < k
, 
decidable: Dec(P)
, 
or: P ∨ Q
, 
satisfiable_int_formula: satisfiable_int_formula(fmla)
, 
select: L[n]
, 
cons: [a / b]
, 
subtract: n - m
Lemmas referenced : 
geo-sep-sym, 
geo-colinear_wf, 
geo-left_wf, 
geo-parallel-points_wf, 
euclidean-plane-structure-subtype, 
euclidean-plane-subtype, 
subtype_rel_transitivity, 
euclidean-plane_wf, 
euclidean-plane-structure_wf, 
geo-primitives_wf, 
geo-point_wf, 
subtype_rel_sets_simple, 
geo-colinear-is-colinear-set, 
length_of_cons_lemma, 
istype-void, 
length_of_nil_lemma, 
decidable__le, 
full-omega-unsat, 
intformnot_wf, 
intformle_wf, 
itermConstant_wf, 
istype-int, 
int_formula_prop_not_lemma, 
int_formula_prop_le_lemma, 
int_term_value_constant_lemma, 
int_formula_prop_wf, 
decidable__lt, 
intformless_wf, 
int_formula_prop_less_lemma, 
istype-le, 
istype-less_than
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
lambdaFormation_alt, 
cut, 
sqequalHypSubstitution, 
productElimination, 
thin, 
independent_pairFormation, 
introduction, 
extract_by_obid, 
dependent_functionElimination, 
hypothesisEquality, 
independent_functionElimination, 
hypothesis, 
voidElimination, 
sqequalRule, 
productIsType, 
setIsType, 
because_Cache, 
universeIsType, 
isectElimination, 
applyEquality, 
setElimination, 
rename, 
instantiate, 
independent_isectElimination, 
inhabitedIsType, 
dependent_pairFormation_alt, 
lambdaEquality_alt, 
isect_memberEquality_alt, 
dependent_set_memberEquality_alt, 
natural_numberEquality, 
unionElimination, 
approximateComputation
Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a,b,c,d:Point.
    (geo-parallel-points(e;a;b;c;d)
    {}\mRightarrow{}  (geo-parallel-points(e;b;a;c;d)
          \mwedge{}  geo-parallel-points(e;a;b;d;c)
          \mwedge{}  geo-parallel-points(e;b;a;d;c)))
Date html generated:
2019_10_16-PM-01_47_14
Last ObjectModification:
2019_08_23-PM-10_05_42
Theory : euclidean!plane!geometry
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