Nuprl Lemma : not-col-distincts
∀e:BasicGeometry. ∀A,B,C:Point.  ((¬Colinear(A;B;C)) 
⇒ (¬¬(A ≠ B ∧ B ≠ C ∧ A ≠ C)))
Proof
Definitions occuring in Statement : 
basic-geometry: BasicGeometry
, 
geo-colinear: Colinear(a;b;c)
, 
geo-sep: a ≠ b
, 
geo-point: Point
, 
all: ∀x:A. B[x]
, 
not: ¬A
, 
implies: P 
⇒ Q
, 
and: P ∧ Q
Definitions unfolded in proof : 
rev_implies: P 
⇐ Q
, 
iff: P 
⇐⇒ Q
, 
geo-eq: a ≡ b
, 
or: P ∨ Q
, 
stable: Stable{P}
, 
cand: A c∧ B
, 
basic-geometry: BasicGeometry
, 
uimplies: b supposing a
, 
guard: {T}
, 
subtype_rel: A ⊆r B
, 
and: P ∧ Q
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
member: t ∈ T
, 
false: False
, 
not: ¬A
, 
implies: P 
⇒ Q
, 
all: ∀x:A. B[x]
Lemmas referenced : 
minimal-not-not-excluded-middle, 
geo-colinear_functionality, 
geo-eq_weakening, 
geo-sep_functionality, 
minimal-double-negation-hyp-elim, 
geo-colinear-same, 
or_wf, 
false_wf, 
stable__false, 
geo-point_wf, 
geo-colinear_wf, 
Error :basic-geo-primitives_wf, 
Error :basic-geo-structure_wf, 
basic-geometry_wf, 
subtype_rel_transitivity, 
basic-geometry-subtype, 
geo-sep_wf, 
not_wf
Rules used in proof : 
impliesLevelFunctionality, 
promote_hyp, 
levelHypothesis, 
andLevelFunctionality, 
dependent_functionElimination, 
impliesFunctionality, 
addLevel, 
unionElimination, 
productElimination, 
independent_pairFormation, 
functionEquality, 
rename, 
setElimination, 
sqequalRule, 
independent_isectElimination, 
instantiate, 
applyEquality, 
hypothesisEquality, 
productEquality, 
isectElimination, 
extract_by_obid, 
introduction, 
voidElimination, 
independent_functionElimination, 
sqequalHypSubstitution, 
hypothesis, 
because_Cache, 
thin, 
cut, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mforall{}e:BasicGeometry.  \mforall{}A,B,C:Point.    ((\mneg{}Colinear(A;B;C))  {}\mRightarrow{}  (\mneg{}\mneg{}(A  \mneq{}  B  \mwedge{}  B  \mneq{}  C  \mwedge{}  A  \mneq{}  C)))
Date html generated:
2017_10_02-PM-06_32_12
Last ObjectModification:
2017_08_05-PM-04_43_01
Theory : euclidean!plane!geometry
Home
Index