Nuprl Lemma : bounded-above-strict

∀[A:Set(ℝ)]. (bounded-above(A) ⇒ (∃b:ℝ. A < b))


Proof




Definitions occuring in Statement :  bounded-above: bounded-above(A),  strict-upper-bound: A < b,  rset: Set(ℝ),  real: ℝ,  uall: ∀[x:A]. B[x],  exists: ∃x:A. B[x],  implies: P ⇒ Q
Definitions unfolded in proof :  bounded-above: bounded-above(A),  uall: ∀[x:A]. B[x],  implies: P ⇒ Q,  exists: ∃x:A. B[x],  member: t ∈ T,  prop: ℙ,  all: ∀x:A. B[x],  nat_plus: ℕ+,  decidable: Dec(P),  or: P ∨ Q,  uimplies: b supposing a,  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  top: Top,  false: False,  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  true: True,  rneq: x ≠ y,  guard: {T},  rdiv: (x/y),  uiff: uiff(P;Q),  req_int_terms: t1 ≡ t2,  upper-bound: A ≤ b,  strict-upper-bound: A < b
Lemmas referenced :  real_wf,  upper-bound_wf,  rset_wf,  rless-int-fractions2,  decidable__lt,  full-omega-unsat,  intformnot_wf,  intformless_wf,  itermConstant_wf,  istype-int,  int_formula_prop_not_lemma,  istype-void,  int_formula_prop_less_lemma,  int_term_value_constant_lemma,  int_formula_prop_wf,  istype-less_than,  radd-preserves-rless,  int-to-real_wf,  rdiv_wf,  rless-int,  rless_wf,  radd_wf,  itermSubtract_wf,  itermAdd_wf,  itermVar_wf,  rmul_wf,  rinv_wf2,  itermMultiply_wf,  strict-upper-bound_wf,  rless_functionality,  req_transitivity,  radd_functionality,  req_weakening,  rinv-as-rdiv,  req-iff-rsub-is-0,  real_polynomial_null,  real_term_value_sub_lemma,  real_term_value_add_lemma,  real_term_value_var_lemma,  real_term_value_const_lemma,  real_term_value_mul_lemma,  rset-member_wf,  rless_transitivity2
Rules used in proof :  sqequalSubstitution,  sqequalRule,  sqequalReflexivity,  sqequalTransitivity,  computationStep,  isect_memberFormation_alt,  lambdaFormation_alt,  sqequalHypSubstitution,  productElimination,  thin,  productIsType,  universeIsType,  cut,  introduction,  extract_by_obid,  hypothesis,  isectElimination,  hypothesisEquality,  dependent_functionElimination,  natural_numberEquality,  dependent_set_memberEquality_alt,  unionElimination,  independent_isectElimination,  approximateComputation,  independent_functionElimination,  dependent_pairFormation_alt,  lambdaEquality_alt,  isect_memberEquality_alt,  voidElimination,  independent_pairFormation,  imageMemberEquality,  baseClosed,  closedConclusion,  inrFormation_alt,  because_Cache,  int_eqEquality,  inhabitedIsType

Latex:
\mforall{}[A:Set(\mBbbR{})].  (bounded-above(A)  {}\mRightarrow{}  (\mexists{}b:\mBbbR{}.  A  <  b))



Date html generated: 2019_10_29-AM-10_39_26
Last ObjectModification: 2019_04_19-PM-06_26_35

Theory : reals


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