Nuprl Lemma : scale-metric-cauchy

∀[X:Type]. ∀[d:metric(X)].  ∀c:{c:ℝ| r0 < c} . ∀x:ℕ ⟶ X.  (mcauchy(d;n.x n) ⇐⇒ mcauchy(c*d;n.x n))


Proof




Definitions occuring in Statement :  mcauchy: mcauchy(d;n.x[n]),  scale-metric: c*d,  metric: metric(X),  rless: x < y,  int-to-real: r(n),  real: ℝ,  nat: ℕ,  uall: ∀[x:A]. B[x],  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  set: {x:A| B[x]} ,  apply: f a,  function: x:A ⟶ B[x],  natural_number: $n,  universe: Type
Definitions unfolded in proof :  uall: ∀[x:A]. B[x],  member: t ∈ T,  all: ∀x:A. B[x],  iff: P ⇐⇒ Q,  and: P ∧ Q,  implies: P ⇒ Q,  subtype_rel: A ⊆r B,  metric-leq: d1 ≤ d2,  uimplies: b supposing a,  rleq: x ≤ y,  rnonneg: rnonneg(x),  le: A ≤ B,  metric: metric(X),  so_lambda: λ2x.t[x],  so_apply: x[s],  prop: ℙ,  rev_implies: P ⇐ Q,  rneq: x ≠ y,  guard: {T},  or: P ∨ Q,  sq_stable: SqStable(P),  squash: ↓T,  less_than: a < b,  less_than': less_than'(a;b),  true: True,  rdiv: (x/y),  uiff: uiff(P;Q),  req_int_terms: t1 ≡ t2,  false: False,  not: ¬A,  top: Top,  scale-metric: c*d,  mdist: mdist(d;x;y),  rev_uimplies: rev_uimplies(P;Q)
Lemmas referenced :  metric-leq-cauchy,  scale-metric_wf,  rleq_weakening_equal,  mdist_wf,  le_witness_for_triv,  mcauchy_wf,  istype-nat,  rdiv_wf,  int-to-real_wf,  sq_stable__rless,  rless_wf,  subtype_rel_sets_simple,  real_wf,  rleq_wf,  rleq_weakening_rless,  metric_wf,  istype-universe,  rmul_preserves_rless,  rmul_wf,  itermSubtract_wf,  itermMultiply_wf,  itermConstant_wf,  itermVar_wf,  rinv_wf2,  rless-int,  rless_functionality,  req_transitivity,  rmul-rinv,  req-iff-rsub-is-0,  real_polynomial_null,  istype-int,  real_term_value_sub_lemma,  istype-void,  real_term_value_mul_lemma,  real_term_value_const_lemma,  real_term_value_var_lemma,  rleq_functionality,  req_weakening,  rmul_functionality
Rules used in proof :  cut,  introduction,  extract_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  isect_memberFormation_alt,  hypothesis,  sqequalHypSubstitution,  isectElimination,  thin,  hypothesisEquality,  lambdaFormation_alt,  independent_pairFormation,  applyEquality,  because_Cache,  sqequalRule,  dependent_functionElimination,  independent_functionElimination,  independent_isectElimination,  lambdaEquality_alt,  productElimination,  equalityTransitivity,  equalitySymmetry,  functionIsTypeImplies,  inhabitedIsType,  universeIsType,  setElimination,  rename,  dependent_set_memberEquality_alt,  closedConclusion,  natural_numberEquality,  inrFormation_alt,  imageMemberEquality,  baseClosed,  imageElimination,  functionIsType,  setIsType,  instantiate,  universeEquality,  approximateComputation,  int_eqEquality,  isect_memberEquality_alt,  voidElimination

Latex:
\mforall{}[X:Type].  \mforall{}[d:metric(X)].    \mforall{}c:\{c:\mBbbR{}|  r0  <  c\}  .  \mforall{}x:\mBbbN{}  {}\mrightarrow{}  X.    (mcauchy(d;n.x  n)  \mLeftarrow{}{}\mRightarrow{}  mcauchy(c*d;n.x  n))



Date html generated: 2019_10_30-AM-06_44_55
Last ObjectModification: 2019_10_02-AM-10_56_50

Theory : reals


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