Nuprl Lemma : real-fun-uniformly-greater

a:ℝ. ∀b:{b:ℝa ≤ b} . ∀f:[a, b] ⟶ℝ.
  (real-fun(f;a;b)
   (∀c:ℝ((∀x:{x:ℝx ∈ [a, b]} (c < (f x)))  (∃c':{c':ℝc < c'} . ∀x:{x:ℝx ∈ [a, b]} (c' ≤ (f x))))))


Proof




Definitions occuring in Statement :  real-fun: real-fun(f;a;b) rfun: I ⟶ℝ rccint: [l, u] i-member: r ∈ I rleq: x ≤ y rless: x < y real: all: x:A. B[x] exists: x:A. B[x] implies:  Q set: {x:A| B[x]}  apply: a
Definitions unfolded in proof :  all: x:A. B[x] implies:  Q member: t ∈ T rfun: I ⟶ℝ uall: [x:A]. B[x] real-fun: real-fun(f;a;b) top: Top uimplies: supposing a prop: and: P ∧ Q iff: ⇐⇒ Q rev_implies:  Q uiff: uiff(P;Q) guard: {T} req_int_terms: t1 ≡ t2 false: False not: ¬A exists: x:A. B[x] sq_stable: SqStable(P) squash: T rev_uimplies: rev_uimplies(P;Q) rge: x ≥ y

Latex:
\mforall{}a:\mBbbR{}.  \mforall{}b:\{b:\mBbbR{}|  a  \mleq{}  b\}  .  \mforall{}f:[a,  b]  {}\mrightarrow{}\mBbbR{}.
    (real-fun(f;a;b)
    {}\mRightarrow{}  (\mforall{}c:\mBbbR{}
                ((\mforall{}x:\{x:\mBbbR{}|  x  \mmember{}  [a,  b]\}  .  (c  <  (f  x)))
                {}\mRightarrow{}  (\mexists{}c':\{c':\mBbbR{}|  c  <  c'\}  .  \mforall{}x:\{x:\mBbbR{}|  x  \mmember{}  [a,  b]\}  .  (c'  \mleq{}  (f  x))))))



Date html generated: 2020_05_20-PM-00_23_17
Last ObjectModification: 2019_12_05-PM-04_28_18

Theory : reals


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