Nuprl Lemma : compact-proper-interval-near-member

∀J:Interval
  (icompact(J)
  ⇒ iproper(J)
  ⇒ (∀x:ℝ. ((x ∈ J) ⇒ (∀r:ℝ. ((r0 < r) ⇒ (∃y:ℝ. ((y ∈ J) ∧ (|y - x| ≤ r) ∧ (r0 < |y - x|))))))))


Proof




Definitions occuring in Statement :  icompact: icompact(I),  i-member: r ∈ I,  iproper: iproper(I),  interval: Interval,  rleq: x ≤ y,  rless: x < y,  rabs: |x|,  rsub: x - y,  int-to-real: r(n),  real: ℝ,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  and: P ∧ Q,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  interval: Interval,  iproper: iproper(I),  icompact: icompact(I),  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 b then t else f fi ,  btrue: tt,  assert: ↑b,  bor: p ∨bq,  bfalse: ff,  i-member: r ∈ I,  right-endpoint: right-endpoint(I),  left-endpoint: left-endpoint(I),  endpoints: endpoints(I),  pi1: fst(t),  pi2: snd(t),  implies: P ⇒ Q,  and: P ∧ Q,  cand: A c∧ B,  true: True,  member: t ∈ T,  prop: ℙ,  uall: ∀[x:A]. B[x],  so_lambda: λ2x.t[x],  so_apply: x[s],  exists: ∃x:A. B[x],  false: False,  or: P ∨ Q,  iff: P ⇐⇒ Q,  uimplies: b supposing a,  itermConstant: "const",  req_int_terms: t1 ≡ t2,  not: ¬A,  top: Top,  uiff: uiff(P;Q),  squash: ↓T,  subtype_rel: A ⊆r B,  guard: {T},  rev_implies: P ⇐ Q,  rev_uimplies: rev_uimplies(P;Q),  rge: x ≥ y,  rsub: x - y
Lemmas referenced :  rless_wf,  int-to-real_wf,  real_wf,  rleq_wf,  true_wf,  exists_wf,  false_wf,  interval_wf,  rless-cases,  rmin_strict_ub,  rsub_wf,  rless-implies-rless,  real_term_polynomial,  itermSubtract_wf,  itermVar_wf,  itermConstant_wf,  real_term_value_const_lemma,  real_term_value_sub_lemma,  real_term_value_var_lemma,  req-iff-rsub-is-0,  itermMinus_wf,  rmin_wf,  real_term_value_minus_lemma,  rminus_wf,  rabs_wf,  squash_wf,  rabs-rminus,  iff_weakening_equal,  rmin-rleq,  rleq_weakening_rless,  rleq_functionality,  rabs_functionality,  req_weakening,  rless_functionality,  rabs-of-nonneg,  radd-preserves-rleq,  radd_wf,  itermAdd_wf,  real_term_value_add_lemma,  rmin_functionality,  rleq_weakening_equal,  rleq_functionality_wrt_implies,  trivial-rsub-rleq,  rmul_wf,  uiff_transitivity,  req_transitivity,  radd_functionality,  rminus-as-rmul,  req_inversion,  rmul-identity1,  rmul-distrib2,  radd-assoc,  rmul_functionality,  radd-int,  rmul-zero-both,  radd-zero-both
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  sqequalHypSubstitution,  productElimination,  thin,  unionElimination,  sqequalRule,  rename,  cut,  hypothesis,  independent_functionElimination,  natural_numberEquality,  independent_pairFormation,  because_Cache,  introduction,  extract_by_obid,  isectElimination,  hypothesisEquality,  productEquality,  functionEquality,  lambdaEquality,  voidElimination,  dependent_functionElimination,  independent_isectElimination,  computeAll,  int_eqEquality,  intEquality,  isect_memberEquality,  voidEquality,  dependent_pairFormation,  addLevel,  applyEquality,  imageElimination,  equalityTransitivity,  equalitySymmetry,  imageMemberEquality,  baseClosed,  universeEquality,  addEquality,  minusEquality,  lemma_by_obid

Latex:
\mforall{}J:Interval
    (icompact(J)
    {}\mRightarrow{}  iproper(J)
    {}\mRightarrow{}  (\mforall{}x:\mBbbR{}.  ((x  \mmember{}  J)  {}\mRightarrow{}  (\mforall{}r:\mBbbR{}.  ((r0  <  r)  {}\mRightarrow{}  (\mexists{}y:\mBbbR{}.  ((y  \mmember{}  J)  \mwedge{}  (|y  -  x|  \mleq{}  r)  \mwedge{}  (r0  <  |y  -  x|))))))))



Date html generated: 2017_10_03-AM-09_35_11
Last ObjectModification: 2017_07_28-AM-07_52_47

Theory : reals


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