Nuprl Lemma : by-nearby-cases
∀[P:ℝ ⟶ ℝ ⟶ ℙ]
  ∀n:ℕ+. ∀x:ℝ.
    ((∀y:{y:ℝ| x < y} . P[x;y])
    
⇒ (∀y:{y:ℝ| y < x} . P[x;y])
    
⇒ (∀y:{y:ℝ| |x - y| ≤ (r1/r(n))} . P[x;y])
    
⇒ (∀y:ℝ. P[x;y]))
Proof
Definitions occuring in Statement : 
rdiv: (x/y)
, 
rleq: x ≤ y
, 
rless: x < y
, 
rabs: |x|
, 
rsub: x - y
, 
int-to-real: r(n)
, 
real: ℝ
, 
nat_plus: ℕ+
, 
uall: ∀[x:A]. B[x]
, 
prop: ℙ
, 
so_apply: x[s1;s2]
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
set: {x:A| B[x]} 
, 
function: x:A ⟶ B[x]
, 
natural_number: $n
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
member: t ∈ T
, 
prop: ℙ
, 
nat_plus: ℕ+
, 
uimplies: b supposing a
, 
rneq: x ≠ y
, 
guard: {T}
, 
or: P ∨ Q
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
rev_implies: P 
⇐ Q
, 
decidable: Dec(P)
, 
satisfiable_int_formula: satisfiable_int_formula(fmla)
, 
exists: ∃x:A. B[x]
, 
false: False
, 
not: ¬A
, 
top: Top
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s1;s2]
, 
so_apply: x[s]
Lemmas referenced : 
nearby-cases-ext, 
real_wf, 
all_wf, 
rleq_wf, 
rabs_wf, 
rsub_wf, 
rdiv_wf, 
int-to-real_wf, 
rless-int, 
nat_plus_properties, 
decidable__lt, 
satisfiable-full-omega-tt, 
intformand_wf, 
intformnot_wf, 
intformless_wf, 
itermConstant_wf, 
itermVar_wf, 
int_formula_prop_and_lemma, 
int_formula_prop_not_lemma, 
int_formula_prop_less_lemma, 
int_term_value_constant_lemma, 
int_term_value_var_lemma, 
int_formula_prop_wf, 
rless_wf, 
nat_plus_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
lambdaFormation, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
dependent_functionElimination, 
thin, 
hypothesisEquality, 
hypothesis, 
isectElimination, 
setEquality, 
because_Cache, 
natural_numberEquality, 
setElimination, 
rename, 
independent_isectElimination, 
sqequalRule, 
inrFormation, 
productElimination, 
independent_functionElimination, 
unionElimination, 
dependent_pairFormation, 
lambdaEquality, 
int_eqEquality, 
intEquality, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
independent_pairFormation, 
computeAll, 
applyEquality, 
functionExtensionality, 
functionEquality, 
cumulativity, 
universeEquality, 
dependent_set_memberEquality
Latex:
\mforall{}[P:\mBbbR{}  {}\mrightarrow{}  \mBbbR{}  {}\mrightarrow{}  \mBbbP{}]
    \mforall{}n:\mBbbN{}\msupplus{}.  \mforall{}x:\mBbbR{}.
        ((\mforall{}y:\{y:\mBbbR{}|  x  <  y\}  .  P[x;y])
        {}\mRightarrow{}  (\mforall{}y:\{y:\mBbbR{}|  y  <  x\}  .  P[x;y])
        {}\mRightarrow{}  (\mforall{}y:\{y:\mBbbR{}|  |x  -  y|  \mleq{}  (r1/r(n))\}  .  P[x;y])
        {}\mRightarrow{}  (\mforall{}y:\mBbbR{}.  P[x;y]))
Date html generated:
2016_10_26-AM-09_12_14
Last ObjectModification:
2016_10_13-AM-10_58_06
Theory : reals
Home
Index