Nuprl Lemma : i-approx-rep

I:Interval. ∀n:ℕ+. ∀r:ℝ.  ((r ∈ i-approx(I;n))  (∃a,b:ℝ((a ≤ b) ∧ (i-approx(I;n) [a, b] ∈ Interval))))


Proof




Definitions occuring in Statement :  i-approx: i-approx(I;n) rccint: [l, u] i-member: r ∈ I interval: Interval rleq: x ≤ y real: nat_plus: + all: x:A. B[x] exists: x:A. B[x] implies:  Q and: P ∧ Q equal: t ∈ T
Definitions unfolded in proof :  all: x:A. B[x] member: t ∈ T implies:  Q prop: uall: [x:A]. B[x] exists: x:A. B[x] uimplies: supposing a and: P ∧ Q cand: c∧ B so_lambda: λ2x.t[x] so_apply: x[s] icompact: icompact(I) interval: Interval i-finite: i-finite(I) i-closed: i-closed(I) i-nonvoid: i-nonvoid(I) isl: isl(x) outl: outl(x) bnot: ¬bb ifthenelse: if then else fi  btrue: tt assert: b bor: p ∨bq bfalse: ff false: False top: Top rccint: [l, u] squash: T true: True
Lemmas referenced :  i-approx-compact i-member_wf i-approx_wf real_wf nat_plus_wf interval_wf equal_wf left-endpoint_wf right-endpoint_wf rleq_wf rccint_wf exists_wf icompact_wf icompact-endpoints-rleq squash_wf true_wf left_endpoint_rccint_lemma right_endpoint_rccint_lemma
Rules used in proof :  cut introduction extract_by_obid sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity lambdaFormation hypothesis sqequalHypSubstitution dependent_functionElimination thin hypothesisEquality independent_functionElimination isectElimination equalityTransitivity equalitySymmetry dependent_pairFormation independent_isectElimination because_Cache independent_pairFormation productEquality sqequalRule lambdaEquality productElimination unionElimination voidElimination applyEquality imageElimination isect_memberEquality voidEquality natural_numberEquality imageMemberEquality baseClosed

Latex:
\mforall{}I:Interval.  \mforall{}n:\mBbbN{}\msupplus{}.  \mforall{}r:\mBbbR{}.    ((r  \mmember{}  i-approx(I;n))  {}\mRightarrow{}  (\mexists{}a,b:\mBbbR{}.  ((a  \mleq{}  b)  \mwedge{}  (i-approx(I;n)  =  [a,  b]))))



Date html generated: 2017_10_03-AM-09_34_39
Last ObjectModification: 2017_07_28-AM-07_52_25

Theory : reals


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