Nuprl Lemma : implies-close-reals

[x,y:ℝ]. ∀[m:ℕ+]. ∀[k:ℕ].  ((|(x m) m| ≤ (2 k))  (|x y| ≤ (r(2 k)/r(m))))


Proof




Definitions occuring in Statement :  rdiv: (x/y) rleq: x ≤ y rabs: |x| rsub: y int-to-real: r(n) real: absval: |i| nat_plus: + nat: uall: [x:A]. B[x] le: A ≤ B implies:  Q apply: a multiply: m subtract: m add: m natural_number: $n
Definitions unfolded in proof :  uall: [x:A]. B[x] member: t ∈ T implies:  Q all: x:A. B[x] rev_uimplies: rev_uimplies(P;Q) real: uimplies: supposing a rge: x ≥ y guard: {T} nat: nat_plus: + rneq: x ≠ y or: P ∨ Q iff: ⇐⇒ Q and: P ∧ Q rev_implies:  Q ge: i ≥  decidable: Dec(P) not: ¬A satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] false: False top: Top prop: uiff: uiff(P;Q) subtype_rel: A ⊆B rleq: x ≤ y rnonneg: rnonneg(x) le: A ≤ B squash: T true: True rational-approx: (x within 1/n) int_nzero: -o nequal: a ≠ b ∈  rless: x < y sq_exists: x:A [B[x]] so_lambda: λ2x.t[x] so_apply: x[s] sq_type: SQType(T) sq_stable: SqStable(P) rdiv: (x/y) req_int_terms: t1 ≡ t2
Lemmas referenced :  rational-approx-property uimplies_transitivity rleq_wf rabs_wf rsub_wf radd_wf rational-approx_wf rleq_functionality_wrt_implies rleq_weakening_equal r-triangle-inequality2 radd_functionality_wrt_rleq rdiv_wf int-to-real_wf rless-int nat_properties nat_plus_properties decidable__lt full-omega-unsat intformand_wf intformnot_wf intformless_wf itermConstant_wf itermVar_wf istype-int int_formula_prop_and_lemma istype-void int_formula_prop_not_lemma int_formula_prop_less_lemma int_term_value_constant_lemma int_term_value_var_lemma int_formula_prop_wf rless_wf rleq_functionality rabs-difference-symmetry req_weakening istype-le absval_wf subtract_wf le_witness_for_triv istype-nat nat_plus_wf real_wf itermMultiply_wf int_term_value_mul_lemma absval_pos decidable__le intformle_wf int_formula_prop_le_lemma squash_wf true_wf rabs-int subtype_rel_self iff_weakening_equal int-rdiv_wf intformeq_wf int_formula_prop_eq_lemma int_subtype_base set_subtype_base less_than_wf nequal_wf uiff_transitivity rabs_functionality rsub_functionality int-rdiv-req req_transitivity rsub-rdiv rabs-rdiv uiff_transitivity2 rdiv_functionality rsub-int rneq_wf subtype_base_sq rleq-int-fractions istype-less_than mul_preserves_le nat_plus_subtype_nat sq_stable__less_than rmul_preserves_rleq rmul_wf rinv_wf2 itermSubtract_wf itermAdd_wf radd_functionality rmul_functionality rmul-rinv rmul-int req_inversion radd-int req-iff-rsub-is-0 real_polynomial_null real_term_value_sub_lemma real_term_value_mul_lemma real_term_value_add_lemma real_term_value_const_lemma real_term_value_var_lemma
Rules used in proof :  sqequalSubstitution sqequalTransitivity computationStep sqequalReflexivity isect_memberFormation_alt introduction cut lambdaFormation_alt extract_by_obid sqequalHypSubstitution dependent_functionElimination thin hypothesisEquality because_Cache isectElimination hypothesis setElimination rename independent_functionElimination independent_isectElimination equalityTransitivity equalitySymmetry addEquality closedConclusion natural_numberEquality sqequalRule inrFormation_alt productElimination unionElimination approximateComputation dependent_pairFormation_alt lambdaEquality_alt int_eqEquality isect_memberEquality_alt voidElimination independent_pairFormation universeIsType applyEquality inhabitedIsType multiplyEquality functionIsTypeImplies isectIsTypeImplies dependent_set_memberEquality_alt imageElimination imageMemberEquality baseClosed instantiate universeEquality equalityIstype baseApply sqequalBase intEquality cumulativity applyLambdaEquality

Latex:
\mforall{}[x,y:\mBbbR{}].  \mforall{}[m:\mBbbN{}\msupplus{}].  \mforall{}[k:\mBbbN{}].    ((|(x  m)  -  y  m|  \mleq{}  (2  *  k))  {}\mRightarrow{}  (|x  -  y|  \mleq{}  (r(2  +  k)/r(m))))



Date html generated: 2019_10_29-AM-10_03_15
Last ObjectModification: 2019_04_23-PM-11_27_06

Theory : reals


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