Nuprl Lemma : less-iff-le

x,y:ℤ.  uiff(x < y;(1 x) ≤ y)


Proof




Definitions occuring in Statement :  less_than: a < b uiff: uiff(P;Q) le: A ≤ B all: x:A. B[x] add: m natural_number: $n int:
Definitions unfolded in proof :  prop: uall: [x:A]. B[x] false: False implies:  Q not: ¬A le: A ≤ B member: t ∈ T uimplies: supposing a and: P ∧ Q uiff: uiff(P;Q) all: x:A. B[x] rev_uimplies: rev_uimplies(P;Q) subtype_rel: A ⊆B squash: T cand: c∧ B less_than: a < b or: P ∨ Q true: True less_than': less_than'(a;b) guard: {T} bool: 𝔹 unit: Unit it: btrue: tt top: Top bfalse: ff exists: x:A. B[x] sq_type: SQType(T) bnot: ¬bb ifthenelse: if then else fi  assert: b iff: ⇐⇒ Q rev_implies:  Q
Lemmas referenced :  le_wf less_than_wf less_than'_wf le-iff-less-or-equal int_subtype_base equal-wf-base lt_int_wf eqtt_to_assert assert_of_lt_int istype-top istype-void eqff_to_assert bool_subtype_base bool_cases_sqequal subtype_base_sq bool_wf iff_transitivity assert_wf bnot_wf not_wf iff_weakening_uiff assert_of_bnot istype-assert zero-add le_reflexive add_functionality_wrt_lt less_than_transitivity1
Rules used in proof :  intEquality equalitySymmetry equalityTransitivity axiomEquality hypothesis natural_numberEquality addEquality isectElimination extract_by_obid voidElimination hypothesisEquality dependent_functionElimination lambdaEquality independent_pairEquality thin productElimination sqequalHypSubstitution sqequalRule cut introduction isect_memberFormation independent_pairFormation lambdaFormation sqequalReflexivity computationStep sqequalTransitivity sqequalSubstitution independent_isectElimination lessCases applyEquality closedConclusion baseApply baseClosed imageMemberEquality inlFormation inrFormation lessDiscrete Error :inhabitedIsType,  Error :lambdaFormation_alt,  unionElimination equalityElimination because_Cache Error :isect_memberFormation_alt,  axiomSqEquality Error :isect_memberEquality_alt,  Error :isectIsTypeImplies,  imageElimination independent_functionElimination Error :dependent_pairFormation_alt,  Error :equalityIsType4,  promote_hyp instantiate cumulativity Error :functionIsType,  Error :equalityIsType1

Latex:
\mforall{}x,y:\mBbbZ{}.    uiff(x  <  y;(1  +  x)  \mleq{}  y)



Date html generated: 2019_06_20-AM-11_23_03
Last ObjectModification: 2018_10_16-PM-02_47_37

Theory : arithmetic


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