Nuprl Lemma : positive-lower-bound_wf

[x:{x:ℝr0 < x} ]. (positive-lower-bound(x) ∈ {k:ℕ+(r1/r(k)) < x} )


Proof




Definitions occuring in Statement :  positive-lower-bound: positive-lower-bound(x) rdiv: (x/y) rless: x < y int-to-real: r(n) real: nat_plus: + uall: [x:A]. B[x] member: t ∈ T set: {x:A| B[x]}  natural_number: $n
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T subtype_rel: A ⊆B all: x:A. B[x] so_lambda: λ2x.t[x] uimplies: supposing a rneq: x ≠ y guard: {T} or: P ∨ Q iff: ⇐⇒ Q and: P ∧ Q rev_implies:  Q implies:  Q nat_plus: + rless: x < y sq_exists: x:{A| B[x]} decidable: Dec(P) satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] false: False not: ¬A top: Top prop: so_apply: x[s] positive-lower-bound: positive-lower-bound(x) pi1: fst(t) small-reciprocal-real-ext has-value: (a)↓ real:
Lemmas referenced :  small-reciprocal-real-ext all_wf exists_wf rless_wf rdiv_wf rless-int nat_plus_properties decidable__lt satisfiable-full-omega-tt intformand_wf intformnot_wf intformless_wf itermConstant_wf itermVar_wf int_formula_prop_and_lemma int_formula_prop_not_lemma int_formula_prop_less_lemma int_term_value_constant_lemma int_term_value_var_lemma int_formula_prop_wf int-to-real_wf set_wf real_wf value-type-has-value set-value-type nat_plus_wf less_than_wf int-value-type rlessw_wf rneq-int intformeq_wf int_formula_prop_eq_lemma equal_wf
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut applyEquality thin instantiate extract_by_obid hypothesis lambdaEquality sqequalHypSubstitution sqequalRule hypothesisEquality isectElimination because_Cache lambdaFormation setElimination rename independent_isectElimination inrFormation dependent_functionElimination productElimination independent_functionElimination unionElimination natural_numberEquality dependent_pairFormation int_eqEquality intEquality isect_memberEquality voidElimination voidEquality independent_pairFormation computeAll dependent_set_memberEquality axiomEquality equalityTransitivity equalitySymmetry callbyvalueReduce addEquality

Latex:
\mforall{}[x:\{x:\mBbbR{}|  r0  <  x\}  ].  (positive-lower-bound(x)  \mmember{}  \{k:\mBbbN{}\msupplus{}|  (r1/r(k))  <  x\}  )



Date html generated: 2016_10_26-AM-09_15_00
Last ObjectModification: 2016_10_12-PM-03_22_09

Theory : reals


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