Nuprl Lemma : band-is-inl
∀[a,b:Top + Top]. ∀[c:Top].  (a ~ inl outl(a)) ∧ (b ~ inl outl(b)) supposing (a ∧b b) = (inl c) ∈ (Top + Top)
Proof
Definitions occuring in Statement : 
band: p ∧b q
, 
outl: outl(x)
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
top: Top
, 
and: P ∧ Q
, 
inl: inl x
, 
union: left + right
, 
sqequal: s ~ t
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
band: p ∧b q
, 
ifthenelse: if b then t else f fi 
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
uimplies: b supposing a
, 
and: P ∧ Q
, 
cand: A c∧ B
, 
outl: outl(x)
, 
bfalse: ff
, 
sq_type: SQType(T)
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
guard: {T}
, 
true: True
, 
false: False
, 
prop: ℙ
, 
subtype_rel: A ⊆r B
, 
bool: 𝔹
, 
top: Top
Lemmas referenced : 
top_wf, 
subtype_base_sq, 
int_subtype_base, 
equal_wf, 
bfalse_wf, 
subtype_rel_union, 
unit_wf2
Rules used in proof : 
sqequalSubstitution, 
sqequalRule, 
sqequalReflexivity, 
sqequalTransitivity, 
computationStep, 
isect_memberFormation, 
introduction, 
cut, 
unionElimination, 
thin, 
sqequalHypSubstitution, 
applyEquality, 
lambdaEquality, 
natural_numberEquality, 
unionEquality, 
lemma_by_obid, 
hypothesis, 
instantiate, 
isectElimination, 
cumulativity, 
intEquality, 
independent_isectElimination, 
dependent_functionElimination, 
equalityTransitivity, 
equalitySymmetry, 
independent_functionElimination, 
voidElimination, 
promote_hyp, 
independent_pairFormation, 
because_Cache, 
productElimination, 
independent_pairEquality, 
sqequalAxiom, 
hypothesisEquality, 
isect_memberEquality, 
voidEquality, 
inlEquality
Latex:
\mforall{}[a,b:Top  +  Top].  \mforall{}[c:Top].    (a  \msim{}  inl  outl(a))  \mwedge{}  (b  \msim{}  inl  outl(b))  supposing  (a  \mwedge{}\msubb{}  b)  =  (inl  c)
Date html generated:
2016_05_13-PM-04_00_03
Last ObjectModification:
2015_12_26-AM-10_49_37
Theory : bool_1
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