Nuprl Lemma : bounded-above-strict

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


Proof




Definitions occuring in Statement :  bounded-above: bounded-above(A) strict-upper-bound: A < b rset: Set(ℝ) real: uall: [x:A]. B[x] exists: x:A. B[x] implies:  Q
Definitions unfolded in proof :  bounded-above: bounded-above(A) uall: [x:A]. B[x] implies:  Q exists: x:A. B[x] member: t ∈ T prop: all: x:A. B[x] nat_plus: + decidable: Dec(P) or: P ∨ Q uimplies: supposing a not: ¬A satisfiable_int_formula: satisfiable_int_formula(fmla) top: Top false: False iff: ⇐⇒ Q and: P ∧ Q rev_implies:  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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