Nuprl Lemma : simple-converges-to

∀x:ℕ ⟶ ℝ. ∀a,c:ℝ.  ((∀n:ℕ. (|(x n) - a| ≤ ((r1/r(2^n)) * c))) ⇒ lim n→∞.x n = a)


Proof




Definitions occuring in Statement :  converges-to: lim n→∞.x[n] = y,  rdiv: (x/y),  rleq: x ≤ y,  rabs: |x|,  rsub: x - y,  rmul: a * b,  int-to-real: r(n),  real: ℝ,  exp: i^n,  nat: ℕ,  all: ∀x:A. B[x],  implies: P ⇒ Q,  apply: f a,  function: x:A ⟶ B[x],  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  implies: P ⇒ Q,  member: t ∈ T,  uall: ∀[x:A]. B[x],  uimplies: b supposing a,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  subtype_rel: A ⊆r B,  nat: ℕ,  so_lambda: λ2x.t[x],  so_apply: x[s],  guard: {T},  int_nzero: ℤ-o,  true: True,  nequal: a ≠ b ∈ T ,  not: ¬A,  sq_type: SQType(T),  false: False,  prop: ℙ,  exists: ∃x:A. B[x],  decidable: Dec(P),  or: P ∨ Q,  sq_exists: ∃x:A [B[x]],  nat_plus: ℕ+,  ge: i ≥ j ,  satisfiable_int_formula: satisfiable_int_formula(fmla),  top: Top,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  uiff: uiff(P;Q),  int_upper: {i...},  le: A ≤ B,  rneq: x ≠ y,  rev_uimplies: rev_uimplies(P;Q),  rdiv: (x/y),  req_int_terms: t1 ≡ t2,  rge: x ≥ y,  converges-to: lim n→∞.x[n] = y
Lemmas referenced :  istype-nat,  rleq_wf,  rabs_wf,  rsub_wf,  rmul_wf,  rdiv_wf,  int-to-real_wf,  exp_wf2,  rneq-int,  not_functionality_wrt_implies,  equal-wf-base,  rationals_wf,  set_subtype_base,  le_wf,  istype-int,  int_subtype_base,  equal_functionality_wrt_subtype_rel2,  int-subtype-rationals,  int_nzero-rational,  exp_wf3,  subtype_base_sq,  nequal_wf,  real_wf,  r-archimedean,  nat_plus_wf,  decidable__equal_int,  nat_plus_properties,  nat_properties,  decidable__le,  full-omega-unsat,  intformnot_wf,  intformle_wf,  itermConstant_wf,  int_formula_prop_not_lemma,  istype-void,  int_formula_prop_le_lemma,  int_term_value_constant_lemma,  int_formula_prop_wf,  istype-le,  le_weakening2,  mul-commutes,  zero-mul,  exp-positive-stronger,  decidable__lt,  intformless_wf,  int_formula_prop_less_lemma,  istype-less_than,  log-property,  log_wf,  add_nat_wf,  add-is-int-iff,  intformand_wf,  itermVar_wf,  itermAdd_wf,  intformeq_wf,  int_formula_prop_and_lemma,  int_term_value_var_lemma,  int_term_value_add_lemma,  int_formula_prop_eq_lemma,  false_wf,  exp-nondecreasing,  itermMultiply_wf,  int_term_value_mul_lemma,  rless-int,  rless_wf,  rmul_preserves_rleq,  rinv_wf2,  itermSubtract_wf,  rleq_functionality,  req_transitivity,  rmul-rinv3,  req-iff-rsub-is-0,  real_polynomial_null,  real_term_value_sub_lemma,  real_term_value_mul_lemma,  real_term_value_const_lemma,  real_term_value_var_lemma,  rleq-int,  rleq_functionality_wrt_implies,  rleq_weakening_equal,  rmul-int,  rmul_functionality,  req_weakening,  rmul-rinv
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation_alt,  cut,  sqequalRule,  functionIsType,  introduction,  extract_by_obid,  hypothesis,  universeIsType,  sqequalHypSubstitution,  isectElimination,  thin,  applyEquality,  hypothesisEquality,  closedConclusion,  natural_numberEquality,  independent_isectElimination,  dependent_functionElimination,  productElimination,  independent_functionElimination,  baseApply,  baseClosed,  intEquality,  lambdaEquality_alt,  because_Cache,  dependent_set_memberEquality_alt,  instantiate,  cumulativity,  equalityTransitivity,  equalitySymmetry,  voidElimination,  equalityIstype,  sqequalBase,  inhabitedIsType,  rename,  setElimination,  unionElimination,  dependent_set_memberFormation_alt,  approximateComputation,  dependent_pairFormation_alt,  isect_memberEquality_alt,  multiplyEquality,  independent_pairFormation,  imageMemberEquality,  addEquality,  applyLambdaEquality,  pointwiseFunctionality,  promote_hyp,  int_eqEquality,  inrFormation_alt

Latex:
\mforall{}x:\mBbbN{}  {}\mrightarrow{}  \mBbbR{}.  \mforall{}a,c:\mBbbR{}.    ((\mforall{}n:\mBbbN{}.  (|(x  n)  -  a|  \mleq{}  ((r1/r(2\^{}n))  *  c)))  {}\mRightarrow{}  lim  n\mrightarrow{}\minfty{}.x  n  =  a)



Date html generated: 2019_10_29-AM-10_10_51
Last ObjectModification: 2019_02_11-PM-02_08_29

Theory : reals


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