Nuprl Lemma : mesh-property
∀I:Interval
  (icompact(I)
  ⇒ (∀p:partition(I). ∀e:ℝ.
        ((r0 < e)
        ⇒ ∀x:ℝ. ((x ∈ I) ⇒ (∃i:ℕ||full-partition(I;p)||. (|x - full-partition(I;p)[i]| ≤ e))) 
           supposing partition-mesh(I;p) ≤ e)))
Proof
Definitions occuring in Statement : 
partition-mesh: partition-mesh(I;p), 
full-partition: full-partition(I;p), 
partition: partition(I), 
icompact: icompact(I), 
i-member: r ∈ I, 
interval: Interval, 
rleq: x ≤ y, 
rless: x < y, 
rabs: |x|, 
rsub: x - y, 
int-to-real: r(n), 
real: ℝ, 
select: L[n], 
length: ||as||, 
int_seg: {i..j-}, 
uimplies: b supposing a, 
all: ∀x:A. B[x], 
exists: ∃x:A. B[x], 
implies: P ⇒ Q, 
natural_number: $n
Definitions unfolded in proof : 
all: ∀x:A. B[x], 
implies: P ⇒ Q, 
uimplies: b supposing a, 
member: t ∈ T, 
rleq: x ≤ y, 
rnonneg: rnonneg(x), 
uall: ∀[x:A]. B[x], 
le: A ≤ B, 
and: P ∧ Q, 
full-partition: full-partition(I;p), 
rless: x < y, 
sq_exists: ∃x:A [B[x]], 
nat_plus: ℕ+, 
decidable: Dec(P), 
or: P ∨ Q, 
partition: partition(I), 
not: ¬A, 
satisfiable_int_formula: satisfiable_int_formula(fmla), 
exists: ∃x:A. B[x], 
false: False, 
prop: ℙ, 
guard: {T}, 
uiff: uiff(P;Q), 
int_seg: {i..j-}, 
lelt: i ≤ j < k, 
subtype_rel: A ⊆r B, 
real: ℝ, 
sq_stable: SqStable(P), 
squash: ↓T, 
sq_type: SQType(T), 
cand: A c∧ B, 
ge: i ≥ j , 
nat: ℕ, 
less_than': less_than'(a;b), 
true: True, 
select: L[n], 
cons: [a / b], 
subtract: n - m, 
less_than: a < b, 
iff: P ⇐⇒ Q, 
rev_implies: P ⇐ Q, 
icompact: icompact(I), 
last: last(L), 
so_lambda: λ2x.t[x], 
so_apply: x[s], 
append: as @ bs, 
list_ind: list_ind, 
nil: [], 
it: ⋅, 
right-endpoint: right-endpoint(I), 
pi2: snd(t), 
endpoints: endpoints(I), 
left-endpoint: left-endpoint(I), 
pi1: fst(t), 
rbetween: x≤y≤z
Latex:
\mforall{}I:Interval
    (icompact(I)
    {}\mRightarrow{}  (\mforall{}p:partition(I).  \mforall{}e:\mBbbR{}.
                ((r0  <  e)
                {}\mRightarrow{}  \mforall{}x:\mBbbR{}.  ((x  \mmember{}  I)  {}\mRightarrow{}  (\mexists{}i:\mBbbN{}||full-partition(I;p)||.  (|x  -  full-partition(I;p)[i]|  \mleq{}  e))) 
                      supposing  partition-mesh(I;p)  \mleq{}  e)))
Date html generated:
2020_05_20-AM-11_37_43
Last ObjectModification:
2019_12_28-PM-09_01_42
Theory : reals
Home
Index