Nuprl Lemma : rational-truncate

∀q:ℚ. ∀e:{e:ℚ| 0 < e} .  (∃q':ℚ [(|q - q'| ≤ e)])


Proof




Definitions occuring in Statement :  qabs: |r|,  qle: r ≤ s,  qless: r < s,  qsub: r - s,  rationals: ℚ,  all: ∀x:A. B[x],  sq_exists: ∃x:A [B[x]],  set: {x:A| B[x]} ,  natural_number: $n
Definitions unfolded in proof :  all: ∀x:A. B[x],  sq_exists: ∃x:A [B[x]],  member: t ∈ T,  prop: ℙ,  uall: ∀[x:A]. B[x],  so_lambda: λ2x.t[x],  subtype_rel: A ⊆r B,  so_apply: x[s],  implies: P ⇒ Q,  bool: 𝔹,  unit: Unit,  it: ⋅,  btrue: tt,  uiff: uiff(P;Q),  and: P ∧ Q,  uimplies: b supposing a,  guard: {T},  iff: P ⇐⇒ Q,  ifthenelse: if b then t else f fi ,  bfalse: ff,  exists: ∃x:A. B[x],  or: P ∨ Q,  sq_type: SQType(T),  bnot: ¬bb,  assert: ↑b,  false: False,  squash: ↓T,  true: True,  pi1: fst(t),  cand: A c∧ B,  pi2: snd(t),  nat_plus: ℕ+,  int_nzero: ℤ-o,  nequal: a ≠ b ∈ T ,  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  top: Top,  mk-rational: mk-rational(a;b),  sq_stable: SqStable(P),  rev_implies: P ⇐ Q,  qsub: r - s
Lemmas referenced :  set_wf,  rationals_wf,  qless_wf,  int-subtype-rationals,  q_less_wf,  bool_wf,  eqtt_to_assert,  assert-q_less-eq,  iff_weakening_equal,  eqff_to_assert,  equal_wf,  bool_cases_sqequal,  subtype_base_sq,  bool_subtype_base,  assert-bnot,  not_wf,  squash_wf,  true_wf,  rational-truncate1,  all_wf,  sq_exists_wf,  nat_plus_wf,  qle_wf,  qabs_wf,  qsub_wf,  qdiv_wf,  subtype_rel_set,  less_than_wf,  int_nzero-rational,  subtype_rel_sets,  nequal_wf,  nat_plus_properties,  satisfiable-full-omega-tt,  intformand_wf,  intformeq_wf,  itermVar_wf,  itermConstant_wf,  intformless_wf,  int_formula_prop_and_lemma,  int_formula_prop_eq_lemma,  int_term_value_var_lemma,  int_term_value_constant_lemma,  int_formula_prop_less_lemma,  int_formula_prop_wf,  equal-wf-base,  int_subtype_base,  qmul_wf,  subtype_rel_transitivity,  int_nzero_wf,  mk-rational_wf,  integer-part_wf,  sq_stable_from_decidable,  decidable__qle,  qdiv-int-elim,  fractional-part_wf,  integer-fractional-parts,  mon_assoc_q,  qadd_ac_1_q,  qadd_wf,  qinverse_q,  mon_ident_q,  qless_complement_qorder,  qabs-of-nonneg,  qless_transitivity_2_qorder,  qle_weakening_lt_qorder
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  dependent_set_memberFormation,  cut,  introduction,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesis,  sqequalRule,  lambdaEquality,  natural_numberEquality,  applyEquality,  hypothesisEquality,  setElimination,  rename,  because_Cache,  unionElimination,  equalityElimination,  equalityTransitivity,  equalitySymmetry,  productElimination,  independent_isectElimination,  independent_functionElimination,  dependent_pairFormation,  promote_hyp,  dependent_functionElimination,  instantiate,  cumulativity,  voidElimination,  imageElimination,  universeEquality,  imageMemberEquality,  baseClosed,  setEquality,  productEquality,  intEquality,  applyLambdaEquality,  int_eqEquality,  isect_memberEquality,  voidEquality,  independent_pairFormation,  computeAll,  functionExtensionality,  dependent_set_memberEquality,  independent_pairEquality,  minusEquality

Latex:
\mforall{}q:\mBbbQ{}.  \mforall{}e:\{e:\mBbbQ{}|  0  <  e\}  .    (\mexists{}q':\mBbbQ{}  [(|q  -  q'|  \mleq{}  e)])



Date html generated: 2018_05_22-AM-00_31_22
Last ObjectModification: 2017_07_26-PM-06_58_59

Theory : rationals


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