Nuprl Lemma : inf-range-no-mc
∀I:{I:Interval| icompact(I)} . ∀f:{f:I ⟶ℝ| ifun(f;I)} .  ∃y:ℝ. inf(f(x)(x∈I)) = y
Proof
Definitions occuring in Statement : 
ifun: ifun(f;I)
, 
rrange: f[x](x∈I)
, 
icompact: icompact(I)
, 
r-ap: f(x)
, 
rfun: I ⟶ℝ
, 
interval: Interval
, 
inf: inf(A) = b
, 
real: ℝ
, 
all: ∀x:A. B[x]
, 
exists: ∃x:A. B[x]
, 
set: {x:A| B[x]} 
Definitions unfolded in proof : 
so_apply: x[s]
, 
uimplies: b supposing a
, 
so_lambda: λ2x.t[x]
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
squash: ↓T
, 
sq_stable: SqStable(P)
, 
implies: P 
⇒ Q
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
Lemmas referenced : 
icompact_wf, 
interval_wf, 
ifun_wf, 
rfun_wf, 
set_wf, 
sq_stable__icompact, 
ifun-continuous, 
inf-range
Rules used in proof : 
independent_isectElimination, 
lambdaEquality, 
isectElimination, 
imageElimination, 
baseClosed, 
imageMemberEquality, 
sqequalRule, 
because_Cache, 
independent_functionElimination, 
hypothesis, 
rename, 
setElimination, 
hypothesisEquality, 
thin, 
dependent_functionElimination, 
sqequalHypSubstitution, 
extract_by_obid, 
introduction, 
cut, 
lambdaFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mforall{}I:\{I:Interval|  icompact(I)\}  .  \mforall{}f:\{f:I  {}\mrightarrow{}\mBbbR{}|  ifun(f;I)\}  .    \mexists{}y:\mBbbR{}.  inf(f(x)(x\mmember{}I))  =  y
Date html generated:
2018_07_29-AM-09_42_17
Last ObjectModification:
2018_06_29-PM-04_31_44
Theory : reals
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