Nuprl Lemma : rexp-approx-for-small

N:ℕ+. ∀x:{x:ℝ|x| ≤ (r1/r(4))} .  (∃z:ℤ [(|e^x (r(z)/r(2 N))| ≤ (r(2)/r(N)))])


Proof




Definitions occuring in Statement :  rexp: e^x rdiv: (x/y) rleq: x ≤ y rabs: |x| rsub: y int-to-real: r(n) real: nat_plus: + all: x:A. B[x] sq_exists: x:A [B[x]] set: {x:A| B[x]}  multiply: m natural_number: $n int:
Definitions unfolded in proof :  all: x:A. B[x] member: t ∈ T sq_exists: x:A [B[x]] uall: [x:A]. B[x] uimplies: supposing a rneq: x ≠ y guard: {T} or: P ∨ Q iff: ⇐⇒ Q and: P ∧ Q rev_implies:  Q implies:  Q nat: nat_plus: + ge: i ≥  decidable: Dec(P) not: ¬A satisfiable_int_formula: satisfiable_int_formula(fmla) exists: x:A. B[x] false: False top: Top prop: less_than: a < b squash: T less_than': less_than'(a;b) true: True subtype_rel: A ⊆B le: A ≤ B uiff: uiff(P;Q) rev_uimplies: rev_uimplies(P;Q) rge: x ≥ y rdiv: (x/y) req_int_terms: t1 ≡ t2
Lemmas referenced :  rexp-approx-lemma-ext rexp-approx_wf rleq_wf rabs_wf rsub_wf 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 itermMultiply_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_mul_lemma int_term_value_var_lemma int_formula_prop_wf rless_wf real_wf nat_plus_wf rexp_wf radd_wf exp_wf2 fact_wf decidable__le intformle_wf int_formula_prop_le_lemma istype-le multiply-is-int-iff false_wf rleq-int-fractions istype-less_than rmul_preserves_rleq rmul_wf rinv_wf2 itermSubtract_wf itermAdd_wf rleq_weakening_equal rleq_functionality_wrt_implies rexp-poly-approx radd_functionality_wrt_rleq rleq_functionality req_transitivity rmul_functionality req_weakening rmul-rinv rmul-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 lambdaFormation_alt cut introduction extract_by_obid sqequalHypSubstitution dependent_functionElimination thin hypothesisEquality setElimination rename dependent_set_memberFormation_alt isectElimination hypothesis universeIsType because_Cache independent_isectElimination sqequalRule inrFormation_alt productElimination independent_functionElimination unionElimination natural_numberEquality approximateComputation dependent_pairFormation_alt lambdaEquality_alt int_eqEquality isect_memberEquality_alt voidElimination independent_pairFormation multiplyEquality setIsType closedConclusion imageMemberEquality baseClosed applyEquality dependent_set_memberEquality_alt inhabitedIsType equalityTransitivity equalitySymmetry pointwiseFunctionality promote_hyp baseApply

Latex:
\mforall{}N:\mBbbN{}\msupplus{}.  \mforall{}x:\{x:\mBbbR{}|  |x|  \mleq{}  (r1/r(4))\}  .    (\mexists{}z:\mBbbZ{}  [(|e\^{}x  -  (r(z)/r(2  *  N))|  \mleq{}  (r(2)/r(N)))])



Date html generated: 2019_10_30-AM-11_40_54
Last ObjectModification: 2019_02_04-AM-10_56_38

Theory : reals_2


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