Nuprl Lemma : m-TB-sup-and-inf

∀[X:Type]
  ∀dX:metric(X)
    (m-TB(X;dX)
    ⇒ (∀f:X ⟶ ℝ. (UC(f:X ⟶ ℝ) ⇒ ((∃a:ℝ. inf(λr.∃x:X. (r = (f x))) = a) ∧ (∃b:ℝ. sup(λr.∃x:X. (r = (f x))) = b)))))


Proof




Definitions occuring in Statement :  m-TB: m-TB(X;d),  m-unif-cont: UC(f:X ⟶ Y),  rmetric: rmetric(),  metric: metric(X),  inf: inf(A) = b,  sup: sup(A) = b,  req: x = y,  real: ℝ,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  and: P ∧ Q,  apply: f a,  lambda: λx.A[x],  function: x:A ⟶ B[x],  universe: Type
Definitions unfolded in proof :  rge: x ≥ y,  less_than: a < b,  le: A ≤ B,  lelt: i ≤ j < k,  int_seg: {i..j-},  rev_implies: P ⇐ Q,  rneq: x ≠ y,  image-ap: f[x],  squash: ↓T,  sq_stable: SqStable(P),  meq: x ≡ y,  rset-member: x ∈ A,  pi1: fst(t),  image-space: f[X],  mdist: mdist(d;x;y),  image-metric: image-metric(d),  rmetric: rmetric(),  cand: A c∧ B,  top: Top,  false: False,  satisfiable_int_formula: satisfiable_int_formula(fmla),  not: ¬A,  or: P ∨ Q,  decidable: Dec(P),  sq_exists: ∃x:A [B[x]],  rless: x < y,  nat_plus: ℕ+,  nat: ℕ,  iff: P ⇐⇒ Q,  totally-bounded: totally-bounded(A),  and: P ∧ Q,  subtype_rel: A ⊆r B,  uimplies: b supposing a,  guard: {T},  exists: ∃x:A. B[x],  prop: ℙ,  rset: Set(ℝ),  member: t ∈ T,  implies: P ⇒ Q,  all: ∀x:A. B[x],  uall: ∀[x:A]. B[x]
Lemmas referenced :  rleq_weakening_equal,  rless_functionality_wrt_implies,  req_weakening,  rsub_functionality,  rabs_functionality,  rless_functionality,  decidable__lt,  int_seg_properties,  rless-int,  rdiv_wf,  image-ap_wf,  rabs-difference-is-zero,  sq_stable__req,  rsub_wf,  rabs_wf,  rset-member_wf,  int_seg_wf,  subtract-add-cancel,  istype-le,  int_formula_prop_wf,  int_formula_prop_less_lemma,  int_term_value_var_lemma,  int_term_value_subtract_lemma,  int_term_value_constant_lemma,  int_formula_prop_le_lemma,  int_formula_prop_not_lemma,  istype-void,  int_formula_prop_and_lemma,  istype-int,  intformless_wf,  itermVar_wf,  itermSubtract_wf,  itermConstant_wf,  intformle_wf,  intformnot_wf,  intformand_wf,  full-omega-unsat,  decidable__le,  nat_plus_properties,  subtract_wf,  image-metric_wf,  image-space_wf,  m-TB-iff,  int-to-real_wf,  rless_wf,  small-reciprocal-real,  istype-universe,  metric_wf,  m-TB_wf,  m-unif-cont_wf,  totally-bounded-sup,  totally-bounded-inf,  subtype_rel_self,  req_transitivity,  req_inversion,  req_wf,  rmetric_wf,  real_wf,  continuous-image-m-TB
Rules used in proof :  inrFormation_alt,  closedConclusion,  imageElimination,  baseClosed,  imageMemberEquality,  equalityIstype,  voidElimination,  isect_memberEquality_alt,  int_eqEquality,  approximateComputation,  unionElimination,  rename,  setElimination,  natural_numberEquality,  universeEquality,  equalitySymmetry,  equalityTransitivity,  independent_pairFormation,  instantiate,  functionIsType,  inhabitedIsType,  because_Cache,  productIsType,  independent_isectElimination,  dependent_pairFormation_alt,  productElimination,  universeIsType,  applyEquality,  productEquality,  sqequalRule,  lambdaEquality_alt,  dependent_set_memberEquality_alt,  independent_functionElimination,  hypothesis,  dependent_functionElimination,  hypothesisEquality,  thin,  isectElimination,  sqequalHypSubstitution,  extract_by_obid,  introduction,  cut,  lambdaFormation_alt,  isect_memberFormation_alt,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution

Latex:
\mforall{}[X:Type]
    \mforall{}dX:metric(X)
        (m-TB(X;dX)
        {}\mRightarrow{}  (\mforall{}f:X  {}\mrightarrow{}  \mBbbR{}
                    (UC(f:X  {}\mrightarrow{}  \mBbbR{})
                    {}\mRightarrow{}  ((\mexists{}a:\mBbbR{}.  inf(\mlambda{}r.\mexists{}x:X.  (r  =  (f  x)))  =  a)  \mwedge{}  (\mexists{}b:\mBbbR{}.  sup(\mlambda{}r.\mexists{}x:X.  (r  =  (f  x)))  =  b)))))



Date html generated: 2019_10_30-AM-06_52_21
Last ObjectModification: 2019_10_25-PM-02_08_02

Theory : reals


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