Nuprl Lemma : eu-colinear-same-side2
∀e:EuclideanPlane
  ∀[A,B,C,D:Point].  (Colinear(A;C;D)) supposing ((¬(A = C ∈ Point)) and (¬(A = B ∈ Point)) and A_B_C and A_B_D)
Proof
Definitions occuring in Statement : 
euclidean-plane: EuclideanPlane
, 
eu-between-eq: a_b_c
, 
eu-colinear: Colinear(a;b;c)
, 
eu-point: Point
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
not: ¬A
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
prop: ℙ
, 
euclidean-plane: EuclideanPlane
, 
false: False
, 
implies: P 
⇒ Q
, 
not: ¬A
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
, 
rev_implies: P 
⇐ Q
, 
and: P ∧ Q
, 
iff: P 
⇐⇒ Q
, 
cand: A c∧ B
Lemmas referenced : 
eu-between-eq-def, 
eu-colinear-def, 
eu-between_wf, 
eu-between-eq-same-side, 
eu-point_wf, 
not_wf, 
equal_wf, 
eu-between-eq_wf, 
euclidean-plane_wf
Rules used in proof : 
rename, 
setElimination, 
equalityEquality, 
voidElimination, 
lambdaEquality, 
sqequalRule, 
introduction, 
independent_isectElimination, 
isectElimination, 
isect_memberFormation, 
hypothesisEquality, 
thin, 
dependent_functionElimination, 
sqequalHypSubstitution, 
hypothesis, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution, 
lemma_by_obid, 
cut, 
because_Cache, 
productEquality, 
independent_pairFormation, 
independent_functionElimination, 
productElimination, 
equalitySymmetry
Latex:
\mforall{}e:EuclideanPlane
    \mforall{}[A,B,C,D:Point].    (Colinear(A;C;D))  supposing  ((\mneg{}(A  =  C))  and  (\mneg{}(A  =  B))  and  A\_B\_C  and  A\_B\_D)
Date html generated:
2016_05_18-AM-06_39_56
Last ObjectModification:
2016_01_01-PM-03_17_21
Theory : euclidean!geometry
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