Nuprl Lemma : eu-eq_dist-axiomA9

e:EuclideanPlane. ∀a1,a2,a3,a4,a5,a6,b:Point.  (D(a1;a2;a3;a4;a5;a6)  (a4 ≠ b ∨ D(a1;a2;a3;b;a5;a6)))


Proof




Definitions occuring in Statement :  dist: D(a;b;c;d;e;f) euclidean-plane: EuclideanPlane geo-sep: a ≠ b geo-point: Point all: x:A. B[x] implies:  Q or: P ∨ Q
Definitions unfolded in proof :  uimplies: supposing a guard: {T} subtype_rel: A ⊆B prop: or: P ∨ Q rev_implies:  Q and: P ∧ Q iff: ⇐⇒ Q euclidean-plane: EuclideanPlane uall: [x:A]. B[x] basic-geometry: BasicGeometry member: t ∈ T implies:  Q all: x:A. B[x]
Lemmas referenced :  geo-point_wf dist_wf geo-primitives_wf euclidean-plane-structure_wf euclidean-plane_wf subtype_rel_transitivity euclidean-plane-subtype euclidean-plane-structure-subtype geo-sep_wf geo-sep-or geo-length_wf geo-add-length_wf geo-lt_wf geo-add-length_wf1 geo-mk-seg_wf geo-length_wf1 geo-sep-iff-or-lt dist-lemma-lt dist-lemma-lt2 geo-add-length-cancel-left-lt geo-le_weakening-lt geo-lt_transitivity geo-lt-lengths-to-sep geo-sep-sym
Rules used in proof :  unionElimination equalitySymmetry equalityTransitivity independent_isectElimination instantiate dependent_set_memberEquality_alt inhabitedIsType lambdaEquality_alt applyEquality universeIsType inlFormation_alt productElimination because_Cache rename setElimination isectElimination sqequalRule hypothesis independent_functionElimination hypothesisEquality thin dependent_functionElimination sqequalHypSubstitution extract_by_obid introduction cut lambdaFormation_alt sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution inrFormation_alt

Latex:
\mforall{}e:EuclideanPlane.  \mforall{}a1,a2,a3,a4,a5,a6,b:Point.
    (D(a1;a2;a3;a4;a5;a6)  {}\mRightarrow{}  (a4  \mneq{}  b  \mvee{}  D(a1;a2;a3;b;a5;a6)))



Date html generated: 2019_10_16-PM-02_57_56
Last ObjectModification: 2019_04_22-PM-01_32_18

Theory : euclidean!plane!geometry


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