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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