Nuprl Lemma : implies-real

[x:ℕ+ ⟶ ℤ]. x ∈ ℝ supposing ∀n,m:ℕ+.  (|(x within 1/n) (x within 1/m)| ≤ ((r1/r(n)) (r1/r(m))))


Proof




Definitions occuring in Statement :  rational-approx: (x within 1/n) rdiv: (x/y) rleq: x ≤ y rabs: |x| rsub: y radd: b int-to-real: r(n) real: nat_plus: + uimplies: supposing a uall: [x:A]. B[x] all: x:A. B[x] member: t ∈ T function: x:A ⟶ B[x] natural_number: $n int:
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T uimplies: supposing a real: nat_plus: + less_than: a < b squash: T less_than': less_than'(a;b) true: True and: P ∧ Q prop: so_lambda: λ2x.t[x] rneq: x ≠ y guard: {T} or: P ∨ Q all: x:A. B[x] iff: ⇐⇒ Q rev_implies:  Q implies:  Q decidable: Dec(P) satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] false: False not: ¬A top: Top so_apply: x[s]
Lemmas referenced :  rless_wf int_formula_prop_wf int_term_value_var_lemma int_term_value_constant_lemma int_formula_prop_less_lemma int_formula_prop_not_lemma int_formula_prop_and_lemma itermVar_wf itermConstant_wf intformless_wf intformnot_wf intformand_wf satisfiable-full-omega-tt decidable__lt nat_plus_properties rless-int int-to-real_wf rdiv_wf radd_wf rational-approx_wf rsub_wf rabs_wf rleq_wf nat_plus_wf all_wf regular-int-seq_wf less_than_wf implies-regular
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation introduction cut dependent_set_memberEquality hypothesisEquality lemma_by_obid sqequalHypSubstitution isectElimination thin natural_numberEquality sqequalRule independent_pairFormation imageMemberEquality baseClosed hypothesis because_Cache independent_isectElimination axiomEquality equalityTransitivity equalitySymmetry lambdaEquality setElimination rename inrFormation dependent_functionElimination productElimination independent_functionElimination unionElimination dependent_pairFormation int_eqEquality intEquality isect_memberEquality voidElimination voidEquality computeAll functionEquality

Latex:
\mforall{}[x:\mBbbN{}\msupplus{}  {}\mrightarrow{}  \mBbbZ{}]
    x  \mmember{}  \mBbbR{}  supposing  \mforall{}n,m:\mBbbN{}\msupplus{}.    (|(x  within  1/n)  -  (x  within  1/m)|  \mleq{}  ((r1/r(n))  +  (r1/r(m))))



Date html generated: 2016_05_18-AM-07_35_21
Last ObjectModification: 2016_01_17-AM-02_02_09

Theory : reals


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