Nuprl Lemma : function-limit

I:Interval. ∀f:I ⟶ℝ. ∀y:ℝ. ∀x:ℕ ⟶ ℝ.
  ((∀x,y:{x:ℝx ∈ 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: y real: nat: so_apply: x[s] all: x:A. B[x] implies:  Q set: {x:A| B[x]}  function: x:A ⟶ B[x]
Definitions unfolded in proof :  so_apply: x[s] prop: squash: T sq_stable: SqStable(P) uimplies: supposing a uall: [x:A]. B[x] rfun: I ⟶ℝ so_lambda: λ2x.t[x] implies:  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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