Nuprl Lemma : reduce-real_wf

∀[k:ℕ+]. ∀[x:ℝ]. ∀[b:{b:ℝ| r0 < b} ].  (reduce-real(x;b;k) ∈ {n:ℤ| |x - r(n) * b| ≤ (b + (b/r(k)))} )


Proof




Definitions occuring in Statement :  reduce-real: reduce-real(x;b;k),  rdiv: (x/y),  rleq: x ≤ y,  rless: x < y,  rabs: |x|,  rsub: x - y,  rmul: a * b,  radd: a + b,  int-to-real: r(n),  real: ℝ,  nat_plus: ℕ+,  uall: ∀[x:A]. B[x],  member: t ∈ T,  set: {x:A| B[x]} ,  natural_number: $n,  int: ℤ
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  all: ∀x:A. B[x],  sq_stable: SqStable(P),  implies: P ⇒ Q,  squash: ↓T,  reduce-real: reduce-real(x;b;k),  uimplies: b supposing a,  rneq: x ≠ y,  or: P ∨ Q,  prop: ℙ,  subtype_rel: A ⊆r B,  nat_plus: ℕ+,  guard: {T},  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  rless: x < y,  sq_exists: ∃x:A [B[x]],  decidable: Dec(P),  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  top: Top,  uiff: uiff(P;Q),  rev_uimplies: rev_uimplies(P;Q),  rdiv: (x/y),  req_int_terms: t1 ≡ t2,  rge: x ≥ y
Lemmas referenced :  sq_stable__rless,  int-to-real_wf,  integer-approx_wf,  rdiv_wf,  rless_wf,  rmul_preserves_rleq2,  rabs_wf,  rsub_wf,  radd_wf,  rless-int,  nat_plus_properties,  decidable__lt,  full-omega-unsat,  intformand_wf,  intformnot_wf,  intformless_wf,  itermConstant_wf,  itermVar_wf,  istype-int,  int_formula_prop_and_lemma,  istype-void,  int_formula_prop_not_lemma,  int_formula_prop_less_lemma,  int_term_value_constant_lemma,  int_term_value_var_lemma,  int_formula_prop_wf,  zero-rleq-rabs,  rleq_wf,  rmul_wf,  real_wf,  nat_plus_wf,  rleq_weakening_rless,  req_weakening,  rminus_wf,  rinv_wf2,  itermSubtract_wf,  itermMultiply_wf,  itermAdd_wf,  itermMinus_wf,  rleq_weakening_equal,  req_functionality,  rabs-of-nonneg,  rleq_functionality,  req_transitivity,  rmul_functionality,  rabs_functionality,  radd_functionality,  rinv-mul-as-rdiv,  req-iff-rsub-is-0,  real_polynomial_null,  real_term_value_sub_lemma,  real_term_value_mul_lemma,  real_term_value_var_lemma,  real_term_value_add_lemma,  real_term_value_minus_lemma,  real_term_value_const_lemma,  req_inversion,  rabs-rmul,  rmul-rinv3,  rleq_functionality_wrt_implies,  rdiv_functionality
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  setElimination,  thin,  rename,  extract_by_obid,  sqequalHypSubstitution,  dependent_functionElimination,  isectElimination,  natural_numberEquality,  hypothesis,  hypothesisEquality,  independent_functionElimination,  sqequalRule,  imageMemberEquality,  baseClosed,  imageElimination,  because_Cache,  independent_isectElimination,  inrFormation_alt,  universeIsType,  applyEquality,  lambdaEquality_alt,  dependent_set_memberEquality_alt,  closedConclusion,  productElimination,  applyLambdaEquality,  unionElimination,  approximateComputation,  dependent_pairFormation_alt,  int_eqEquality,  isect_memberEquality_alt,  voidElimination,  independent_pairFormation,  promote_hyp,  inhabitedIsType,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  setIsType,  isectIsTypeImplies

Latex:
\mforall{}[k:\mBbbN{}\msupplus{}].  \mforall{}[x:\mBbbR{}].  \mforall{}[b:\{b:\mBbbR{}|  r0  <  b\}  ].    (reduce-real(x;b;k)  \mmember{}  \{n:\mBbbZ{}|  |x  -  r(n)  *  b|  \mleq{}  (b  +  (b/r(k)))\}  \000C)



Date html generated: 2019_10_29-AM-10_09_22
Last ObjectModification: 2019_02_03-PM-03_15_46

Theory : reals


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