Nuprl Lemma : cosine-poly-approx

∀[x:{x:ℝ| |x| ≤ (r1/r(2))} ]. ∀[k:ℕ]. ∀[N:ℕ+].
  (|cosine(x) - (r(cosine-approx(x;k;N))/r(2 * N))| ≤ ((|x|^(2 * k) + 2/r(((2 * k) + 2)!)) + (r1/r(N))))


Proof




Definitions occuring in Statement :  cosine-approx: cosine-approx(x;k;N),  cosine: cosine(x),  rdiv: (x/y),  rleq: x ≤ y,  rabs: |x|,  rnexp: x^k1,  rsub: x - y,  radd: a + b,  int-to-real: r(n),  real: ℝ,  fact: (n)!,  nat_plus: ℕ+,  nat: ℕ,  uall: ∀[x:A]. B[x],  set: {x:A| B[x]} ,  multiply: n * m,  add: n + m,  natural_number: $n
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  implies: P ⇒ Q,  uimplies: b supposing a,  rneq: x ≠ y,  guard: {T},  or: P ∨ Q,  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q,  rev_implies: P ⇐ Q,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  true: True,  prop: ℙ,  sq_stable: SqStable(P),  ireal-approx: j-approx(x;M;z),  rev_uimplies: rev_uimplies(P;Q),  nat_plus: ℕ+,  nat: ℕ,  ge: i ≥ j ,  decidable: Dec(P),  not: ¬A,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  false: False,  top: Top,  so_lambda: λ2x.t[x],  subtype_rel: A ⊆r B,  le: A ≤ B,  int_seg: {i..j-},  lelt: i ≤ j < k,  so_apply: x[s],  rge: x ≥ y,  cand: A c∧ B,  uiff: uiff(P;Q),  stable: Stable{P}
Lemmas referenced :  cosine-approx-property,  sq_stable__rleq,  rabs_wf,  rdiv_wf,  int-to-real_wf,  rless-int,  rless_wf,  rleq_functionality_wrt_implies,  rsub_wf,  cosine_wf,  cosine-approx_wf,  nat_plus_properties,  nat_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,  radd_wf,  rsum_wf,  int-rmul_wf,  fastexp_wf,  int_seg_subtype_nat,  istype-false,  int-rdiv_wf,  fact_wf,  int_seg_properties,  decidable__le,  intformle_wf,  int_formula_prop_le_lemma,  istype-le,  rnexp_wf,  int_seg_wf,  rleq_weakening_equal,  r-triangle-inequality2,  itermAdd_wf,  int_term_value_add_lemma,  radd_functionality_wrt_rleq,  nat_plus_wf,  istype-nat,  real_wf,  rleq_wf,  cosine-poly-approx-1,  zero-rleq-rabs,  rleq-int-fractions3,  istype-less_than,  rleq_transitivity,  rleq_functionality,  radd_functionality,  req_weakening,  rabs_functionality,  rsub_functionality,  nat_plus_inc_int_nzero,  stable_req,  false_wf,  not_wf,  req_wf,  minimal-double-negation-hyp-elim,  minimal-not-not-excluded-middle,  rabs-of-nonpos,  rleq_weakening_rless,  rminus_wf,  req_functionality,  cosine_functionality,  cosine-rminus,  not-rless,  rabs-of-nonneg,  rnexp-nonneg,  rnexp2-nonneg,  rsum_functionality2,  int-rmul_functionality,  int-rdiv_functionality,  req_inversion,  rabs-rnexp,  rnexp-mul
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  hypothesis,  sqequalHypSubstitution,  isectElimination,  thin,  setElimination,  rename,  hypothesisEquality,  independent_functionElimination,  closedConclusion,  natural_numberEquality,  independent_isectElimination,  sqequalRule,  inrFormation_alt,  dependent_functionElimination,  because_Cache,  productElimination,  independent_pairFormation,  imageMemberEquality,  baseClosed,  universeIsType,  imageElimination,  multiplyEquality,  unionElimination,  approximateComputation,  dependent_pairFormation_alt,  lambdaEquality_alt,  int_eqEquality,  isect_memberEquality_alt,  voidElimination,  minusEquality,  applyEquality,  lambdaFormation_alt,  dependent_set_memberEquality_alt,  addEquality,  inhabitedIsType,  equalityTransitivity,  equalitySymmetry,  applyLambdaEquality,  setIsType,  productIsType,  unionEquality,  functionEquality,  functionIsType,  unionIsType

Latex:
\mforall{}[x:\{x:\mBbbR{}|  |x|  \mleq{}  (r1/r(2))\}  ].  \mforall{}[k:\mBbbN{}].  \mforall{}[N:\mBbbN{}\msupplus{}].
    (|cosine(x)  -  (r(cosine-approx(x;k;N))/r(2  *  N))|  \mleq{}  ((|x|\^{}(2  *  k)  +  2/r(((2  *  k)  +  2)!))
    +  (r1/r(N))))



Date html generated: 2019_10_29-AM-10_37_16
Last ObjectModification: 2019_02_02-PM-00_23_11

Theory : reals


Home Index