Nuprl Lemma : absval_sym

[i:ℤ]. (|i| |-i| ∈ ℤ)


Proof




Definitions occuring in Statement :  absval: |i| uall: [x:A]. B[x] minus: -n int: equal: t ∈ T
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T squash: T prop: subtype_rel: A ⊆B nat: true: True uimplies: supposing a guard: {T} iff: ⇐⇒ Q and: P ∧ Q rev_implies:  Q implies:  Q
Lemmas referenced :  equal_wf squash_wf true_wf absval_wf nat_wf absval-minus iff_weakening_equal
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation cut applyEquality thin lambdaEquality sqequalHypSubstitution imageElimination introduction extract_by_obid isectElimination hypothesisEquality equalityTransitivity hypothesis equalitySymmetry universeEquality intEquality setElimination rename sqequalRule natural_numberEquality imageMemberEquality baseClosed independent_isectElimination productElimination independent_functionElimination because_Cache

Latex:
\mforall{}[i:\mBbbZ{}].  (|i|  =  |-i|)



Date html generated: 2017_04_14-AM-07_17_15
Last ObjectModification: 2017_02_27-PM-02_51_55

Theory : arithmetic


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