Nuprl Lemma : function-limit

∀I:Interval. ∀f:I ⟶ℝ. ∀y:ℝ. ∀x:ℕ ⟶ ℝ.
  ((∀x,y:{x:ℝ| x ∈ I} .  ((x = y) ⇒ (f(x) = f(y))))
  ⇒ lim n→∞.x[n] = y
  ⇒ (y ∈ I)
  ⇒ (∀n:ℕ. (x[n] ∈ I))
  ⇒ lim n→∞.f(x[n]) = f(y))


Proof




Definitions occuring in Statement :  r-ap: f(x),  rfun: I ⟶ℝ,  i-member: r ∈ I,  interval: Interval,  converges-to: lim n→∞.x[n] = y,  req: x = y,  real: ℝ,  nat: ℕ,  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  set: {x:A| B[x]} ,  function: x:A ⟶ B[x]
Definitions unfolded in proof :  so_apply: x[s],  prop: ℙ,  squash: ↓T,  sq_stable: SqStable(P),  uimplies: b supposing a,  uall: ∀[x:A]. B[x],  rfun: I ⟶ℝ,  so_lambda: λ2x.t[x],  implies: P ⇒ Q,  member: t ∈ T,  all: ∀x:A. B[x]
Lemmas referenced :  interval_wf,  rfun_wf,  nat_wf,  req_wf,  all_wf,  i-member_wf,  real_wf,  sq_stable__i-member,  r-ap_wf,  function-is-continuous,  continuous-limit
Rules used in proof :  functionEquality,  setEquality,  imageElimination,  baseClosed,  imageMemberEquality,  independent_isectElimination,  because_Cache,  rename,  setElimination,  isectElimination,  lambdaEquality,  sqequalRule,  independent_functionElimination,  hypothesisEquality,  thin,  dependent_functionElimination,  sqequalHypSubstitution,  hypothesis,  lambdaFormation,  sqequalReflexivity,  computationStep,  sqequalTransitivity,  sqequalSubstitution,  extract_by_obid,  introduction,  cut

Latex:
\mforall{}I:Interval.  \mforall{}f:I  {}\mrightarrow{}\mBbbR{}.  \mforall{}y:\mBbbR{}.  \mforall{}x:\mBbbN{}  {}\mrightarrow{}  \mBbbR{}.
    ((\mforall{}x,y:\{x:\mBbbR{}|  x  \mmember{}  I\}  .    ((x  =  y)  {}\mRightarrow{}  (f(x)  =  f(y))))
    {}\mRightarrow{}  lim  n\mrightarrow{}\minfty{}.x[n]  =  y
    {}\mRightarrow{}  (y  \mmember{}  I)
    {}\mRightarrow{}  (\mforall{}n:\mBbbN{}.  (x[n]  \mmember{}  I))
    {}\mRightarrow{}  lim  n\mrightarrow{}\minfty{}.f(x[n])  =  f(y))



Date html generated: 2017_10_03-AM-10_19_08
Last ObjectModification: 2017_07_31-AM-11_47_30

Theory : reals


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