Nuprl Lemma : reduce-halfpi_wf

∀[x:ℝ]. (reduce-halfpi(x) ∈ {n:ℤ| |x - r(n) * π/2| ≤ r(2)} )


Proof




Definitions occuring in Statement :  reduce-halfpi: reduce-halfpi(x),  halfpi: π/2,  rleq: x ≤ y,  rabs: |x|,  rsub: x - y,  rmul: a * b,  int-to-real: r(n),  real: ℝ,  uall: ∀[x:A]. B[x],  member: t ∈ T,  set: {x:A| B[x]} ,  natural_number: $n,  int: ℤ
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  reduce-halfpi: reduce-halfpi(x),  nat_plus: ℕ+,  less_than: a < b,  squash: ↓T,  less_than': less_than'(a;b),  true: True,  and: P ∧ Q,  subtype_rel: A ⊆r B,  prop: ℙ,  rless: x < y,  sq_exists: ∃x:A [B[x]],  all: ∀x:A. B[x],  decidable: Dec(P),  or: P ∨ Q,  uimplies: b supposing a,  not: ¬A,  implies: P ⇒ Q,  satisfiable_int_formula: satisfiable_int_formula(fmla),  exists: ∃x:A. B[x],  top: Top,  false: False,  real: ℝ,  int-to-real: r(n),  int-rmul: k1 * a,  MachinPi4: MachinPi4(),  rsub: x - y,  radd: a + b,  accelerate: accelerate(k;f),  reg-seq-list-add: reg-seq-list-add(L),  cbv_list_accum: cbv_list_accum(x,a.f[x; a];y;L),  cons: [a / b],  atan: atan(a;x),  atan_approx: atan_approx(a;x;M),  atan-log: atan-log(a;M),  gen_log_aux: gen_log_aux(p;c;x;i;n;M),  ifthenelse: if b then t else f fi ,  le_int: i ≤z j,  bnot: ¬bb,  lt_int: i <z j,  exp: i^n,  primrec: primrec(n;b;c),  primtailrec: primtailrec(n;i;b;f),  subtract: n - m,  btrue: tt,  bfalse: ff,  atan-approx: atan-approx(k;x;N),  poly-approx: poly-approx(a;x;k;N),  rmul: a * b,  int-rdiv: (a)/k1,  imax: imax(a;b),  absval: |i|,  reg-seq-mul: reg-seq-mul(x;y),  poly-approx-aux: poly-approx-aux(a;x;xM;M;n;k),  eq_int: (i =z j),  rminus: -(x),  nil: [],  it: ⋅,  guard: {T},  rdiv: (x/y),  rinv: rinv(x),  mu-ge: mu-ge(f;n),  reg-seq-inv: reg-seq-inv(x),  rneq: x ≠ y,  iff: P ⇐⇒ Q,  rev_implies: P ⇐ Q,  uiff: uiff(P;Q),  rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced :  reduce-real_wf,  istype-less_than,  real_wf,  int-rmul_wf,  MachinPi4_wf,  rless_wf,  int-to-real_wf,  decidable__lt,  full-omega-unsat,  intformnot_wf,  intformless_wf,  itermConstant_wf,  istype-int,  int_formula_prop_not_lemma,  istype-void,  int_formula_prop_less_lemma,  int_term_value_constant_lemma,  int_formula_prop_wf,  rleq_wf,  rabs_wf,  rsub_wf,  rmul_wf,  halfpi_wf,  radd_wf,  rdiv_wf,  rless-int,  rless_transitivity2,  rleq_weakening_rless,  rleq_functionality,  rabs_functionality,  rsub_functionality,  req_weakening,  rmul_functionality,  req_inversion,  2-MachinPi4
Rules used in proof :  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  introduction,  cut,  extract_by_obid,  sqequalHypSubstitution,  isectElimination,  thin,  dependent_set_memberEquality_alt,  closedConclusion,  natural_numberEquality,  sqequalRule,  independent_pairFormation,  imageMemberEquality,  hypothesisEquality,  baseClosed,  hypothesis,  applyEquality,  axiomEquality,  equalityTransitivity,  equalitySymmetry,  universeIsType,  lambdaEquality_alt,  setElimination,  rename,  inhabitedIsType,  dependent_set_memberFormation_alt,  dependent_functionElimination,  unionElimination,  independent_isectElimination,  approximateComputation,  independent_functionElimination,  dependent_pairFormation_alt,  isect_memberEquality_alt,  voidElimination,  addEquality,  applyLambdaEquality,  imageElimination,  because_Cache,  inrFormation_alt,  productElimination

Latex:
\mforall{}[x:\mBbbR{}].  (reduce-halfpi(x)  \mmember{}  \{n:\mBbbZ{}|  |x  -  r(n)  *  \mpi{}/2|  \mleq{}  r(2)\}  )



Date html generated: 2019_10_31-AM-06_06_59
Last ObjectModification: 2019_02_03-PM-04_44_49

Theory : reals_2


Home Index