Nuprl Lemma : mod2-cases

x:ℤ(((x mod 2) 0 ∈ ℤ) ∨ ((x mod 2) 1 ∈ ℤ))


Proof




Definitions occuring in Statement :  modulus: mod n all: x:A. B[x] or: P ∨ Q natural_number: $n int: equal: t ∈ T
Definitions unfolded in proof :  subtract: m top: Top uiff: uiff(P;Q) rev_implies:  Q iff: ⇐⇒ Q le: A ≤ B or: P ∨ Q decidable: Dec(P) subtype_rel: A ⊆B false: False guard: {T} sq_type: SQType(T) uimplies: supposing a implies:  Q not: ¬A nequal: a ≠ b ∈  int_nzero: -o prop: and: P ∧ Q true: True less_than': less_than'(a;b) squash: T less_than: a < b nat_plus: + member: t ∈ T uall: [x:A]. B[x] all: x:A. B[x]
Lemmas referenced :  less-iff-le or_wf le_antisymmetry_iff add-swap le-add-cancel2 minus-zero minus-add add-commutes condition-implies-le le-add-cancel zero-add add-zero add-associates add_functionality_wrt_le not-equal-2 false_wf equal_wf nequal_wf true_wf equal-wf-base int_subtype_base subtype_base_sq modulus_wf decidable__int_equal less_than_wf mod_bounds
Rules used in proof :  orFunctionality minusEquality voidEquality isect_memberEquality lambdaEquality addEquality inrFormation inlFormation unionElimination because_Cache applyEquality voidElimination independent_functionElimination equalitySymmetry equalityTransitivity independent_isectElimination intEquality cumulativity instantiate addLevel productElimination dependent_functionElimination hypothesis baseClosed imageMemberEquality independent_pairFormation sqequalRule natural_numberEquality dependent_set_memberEquality hypothesisEquality thin isectElimination sqequalHypSubstitution extract_by_obid introduction cut lambdaFormation sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution

Latex:
\mforall{}x:\mBbbZ{}.  (((x  mod  2)  =  0)  \mvee{}  ((x  mod  2)  =  1))



Date html generated: 2020_05_19-PM-09_35_40
Last ObjectModification: 2019_12_16-PM-02_26_13

Theory : arithmetic


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