Nuprl Lemma : rless-cases
∀x,y:ℝ.  ((x < y) 
⇒ (∀z:ℝ. ((x < z) ∨ (z < y))))
Proof
Definitions occuring in Statement : 
rless: x < y
, 
real: ℝ
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
or: P ∨ Q
Definitions unfolded in proof : 
member: t ∈ T
, 
rless-cases-proof, 
rless-iff8, 
decidable__lt, 
decidable__squash, 
uall: ∀[x:A]. B[x]
, 
so_lambda: so_lambda(x,y,z,w.t[x; y; z; w])
, 
so_apply: x[s1;s2;s3;s4]
, 
top: Top
, 
uimplies: b supposing a
, 
strict4: strict4(F)
, 
and: P ∧ Q
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
has-value: (a)↓
, 
prop: ℙ
, 
guard: {T}
, 
or: P ∨ Q
, 
squash: ↓T
, 
so_lambda: λ2x y.t[x; y]
, 
so_apply: x[s1;s2]
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
decidable_functionality, 
iff_preserves_decidability, 
decidable__and, 
decidable__less_than', 
rless-case: rless-case(x;y;n;z)
Lemmas referenced : 
rless-cases-proof, 
lifting-strict-spread, 
has-value_wf_base, 
base_wf, 
is-exception_wf, 
top_wf, 
equal_wf, 
lifting-strict-decide, 
lifting-strict-less, 
rless-iff8, 
decidable__lt, 
decidable__squash, 
decidable_functionality, 
iff_preserves_decidability, 
decidable__and, 
decidable__less_than'
Rules used in proof : 
introduction, 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
cut, 
instantiate, 
extract_by_obid, 
hypothesis, 
sqequalRule, 
thin, 
sqequalHypSubstitution, 
isectElimination, 
baseClosed, 
isect_memberEquality, 
voidElimination, 
voidEquality, 
independent_isectElimination, 
independent_pairFormation, 
lambdaFormation, 
callbyvalueApply, 
baseApply, 
closedConclusion, 
hypothesisEquality, 
applyExceptionCases, 
inrFormation, 
imageMemberEquality, 
imageElimination, 
exceptionSqequal, 
inlFormation, 
callbyvalueDecide, 
equalityTransitivity, 
equalitySymmetry, 
unionEquality, 
unionElimination, 
sqleReflexivity, 
dependent_functionElimination, 
independent_functionElimination, 
decideExceptionCases, 
because_Cache
Latex:
\mforall{}x,y:\mBbbR{}.    ((x  <  y)  {}\mRightarrow{}  (\mforall{}z:\mBbbR{}.  ((x  <  z)  \mvee{}  (z  <  y))))
Date html generated:
2017_10_03-AM-08_46_36
Last ObjectModification:
2017_07_28-AM-07_32_44
Theory : reals
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