Nuprl Lemma : continuous-implies-functional

∀I:Interval. ∀f:I ⟶ℝ.  (f[x] continuous for x ∈ I ⇒ (∀a,b:{x:ℝ| x ∈ I} .  ((a = b) ⇒ (f[a] = f[b]))))


Proof




Definitions occuring in Statement :  continuous: f[x] continuous for x ∈ I,  rfun: I ⟶ℝ,  i-member: r ∈ I,  interval: Interval,  req: x = y,  real: ℝ,  so_apply: x[s],  all: ∀x:A. B[x],  implies: P ⇒ Q,  set: {x:A| B[x]} 
Definitions unfolded in proof :  all: ∀x:A. B[x],  member: t ∈ T,  implies: P ⇒ Q,  uall: ∀[x:A]. B[x],  so_apply: x[s],  rfun: I ⟶ℝ,  uimplies: b supposing a,  not: ¬A,  rneq: x ≠ y,  or: P ∨ Q,  guard: {T},  false: False,  prop: ℙ,  so_lambda: λ2x.t[x],  label: ...$L... t
Lemmas referenced :  continuous-rneq,  not-rneq,  req_inversion,  rless_transitivity1,  rleq_weakening,  rless_irreflexivity,  rneq_wf,  req_wf,  real_wf,  i-member_wf,  continuous_wf,  rfun_wf,  interval_wf
Rules used in proof :  cut,  lemma_by_obid,  sqequalSubstitution,  sqequalTransitivity,  computationStep,  sqequalReflexivity,  lambdaFormation,  hypothesis,  sqequalHypSubstitution,  dependent_functionElimination,  thin,  hypothesisEquality,  independent_functionElimination,  isectElimination,  applyEquality,  sqequalRule,  independent_isectElimination,  unionElimination,  setElimination,  rename,  because_Cache,  voidElimination,  setEquality,  lambdaEquality

Latex:
\mforall{}I:Interval.  \mforall{}f:I  {}\mrightarrow{}\mBbbR{}.
    (f[x]  continuous  for  x  \mmember{}  I  {}\mRightarrow{}  (\mforall{}a,b:\{x:\mBbbR{}|  x  \mmember{}  I\}  .    ((a  =  b)  {}\mRightarrow{}  (f[a]  =  f[b]))))



Date html generated: 2016_05_18-AM-09_09_09
Last ObjectModification: 2015_12_27-PM-11_30_27

Theory : reals


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