Nuprl Lemma : dense-in-reals-implies

∀X:ℝ ⟶ ℙ
  (dense-in-interval((-∞, ∞);X)
  ⇒ (∀x:ℝ. ∀y:{y:ℝ| y = x} .  ((X x) ⇒ (X y)))
  ⇒ (∀x:ℝ. ∃x':ℝ. ((x' = x) ∧ (∀k:ℕ+. ∃y:ℝ. ((y = x' ∈ (ℕ+k ⟶ ℤ)) ∧ (X y))))))


Proof




Definitions occuring in Statement :  dense-in-interval: dense-in-interval(I;X),  riiint: (-∞, ∞),  req: x = y,  real: ℝ,  int_seg: {i..j-},  nat_plus: ℕ+,  prop: ℙ,  all: ∀x:A. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q,  and: P ∧ Q,  set: {x:A| B[x]} ,  apply: f a,  function: x:A ⟶ B[x],  natural_number: $n,  int: ℤ,  equal: s = t ∈ T
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  implies: P ⇒ Q,  exists: ∃x:A. B[x],  uall: ∀[x:A]. B[x],  nat_plus: ℕ+,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  true: True,  and: P ∧ Q,  prop: ℙ,  subtype_rel: A ⊆r B,  real: ℝ,  so_lambda: λ2x.t[x],  so_apply: x[s],  uimplies: b supposing a,  cand: A c∧ B,  le: A ≤ B,  false: False,  not: ¬A,  top: Top
Lemmas referenced :  dense-in-reals-implies-accel,  accelerate_wf,  less_than_wf,  subtype_rel_sets,  nat_plus_wf,  regular-int-seq_wf,  real-regular,  accelerate-req,  req_wf,  all_wf,  exists_wf,  real_wf,  equal_wf,  int_seg_wf,  subtype_rel_dep_function,  int_seg_subtype_nat_plus,  false_wf,  subtype_rel_self,  dense-in-interval_wf,  riiint_wf,  i-member_wf,  member_riiint_lemma,  set_wf
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  hypothesis,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  independent_functionElimination,  dependent_pairFormation,  isectElimination,  dependent_set_memberEquality,  natural_numberEquality,  sqequalRule,  independent_pairFormation,  imageMemberEquality,  baseClosed,  applyEquality,  functionEquality,  intEquality,  because_Cache,  lambdaEquality,  functionExtensionality,  independent_isectElimination,  setElimination,  rename,  setEquality,  productElimination,  productEquality,  universeEquality,  instantiate,  cumulativity,  isect_memberEquality,  voidElimination,  voidEquality

Latex:
\mforall{}X:\mBbbR{}  {}\mrightarrow{}  \mBbbP{}
    (dense-in-interval((-\minfty{},  \minfty{});X)
    {}\mRightarrow{}  (\mforall{}x:\mBbbR{}.  \mforall{}y:\{y:\mBbbR{}|  y  =  x\}  .    ((X  x)  {}\mRightarrow{}  (X  y)))
    {}\mRightarrow{}  (\mforall{}x:\mBbbR{}.  \mexists{}x':\mBbbR{}.  ((x'  =  x)  \mwedge{}  (\mforall{}k:\mBbbN{}\msupplus{}.  \mexists{}y:\mBbbR{}.  ((y  =  x')  \mwedge{}  (X  y))))))



Date html generated: 2017_10_03-AM-10_10_38
Last ObjectModification: 2017_09_19-PM-01_03_15

Theory : reals


Home Index