Nuprl Lemma : bag-combine-eq-right
∀[A,B:Type]. ∀[b:bag(A)]. ∀[f1,f2:A ⟶ bag(B)].
  ⋃x∈b.f1[x] = ⋃x∈b.f2[x] ∈ bag(B) supposing ∀x:{x:A| x ↓∈ b} . (f1[x] = f2[x] ∈ bag(B))
Proof
Definitions occuring in Statement : 
bag-member: x ↓∈ bs
, 
bag-combine: ⋃x∈bs.f[x]
, 
bag: bag(T)
, 
uimplies: b supposing a
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s]
, 
all: ∀x:A. B[x]
, 
set: {x:A| B[x]} 
, 
function: x:A ⟶ B[x]
, 
universe: Type
, 
equal: s = t ∈ T
Definitions unfolded in proof : 
bag-combine: ⋃x∈bs.f[x]
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
squash: ↓T
, 
exists: ∃x:A. B[x]
, 
prop: ℙ
, 
so_lambda: λ2x.t[x]
, 
so_apply: x[s]
, 
bag-map: bag-map(f;bs)
, 
true: True
, 
uimplies: b supposing a
, 
subtype_rel: A ⊆r B
, 
guard: {T}
, 
iff: P 
⇐⇒ Q
, 
and: P ∧ Q
, 
rev_implies: P 
⇐ Q
, 
implies: P 
⇒ Q
, 
all: ∀x:A. B[x]
, 
nat: ℕ
, 
int_seg: {i..j-}
, 
lelt: i ≤ j < k
, 
le: A ≤ B
Lemmas referenced : 
bag_to_squash_list, 
all_wf, 
bag-member_wf, 
equal_wf, 
bag_wf, 
bag-map_wf, 
bag-union_wf, 
squash_wf, 
true_wf, 
iff_weakening_equal, 
map_equal, 
select_wf, 
bag-member-select, 
lelt_wf, 
length_wf, 
list-subtype-bag, 
less_than_wf, 
nat_wf, 
length_wf_nat, 
map_wf, 
subtype_rel_self, 
subtype_rel_set, 
list_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
cut, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
thin, 
because_Cache, 
hypothesisEquality, 
imageElimination, 
productElimination, 
promote_hyp, 
hypothesis, 
equalitySymmetry, 
hyp_replacement, 
applyLambdaEquality, 
setEquality, 
cumulativity, 
sqequalRule, 
lambdaEquality, 
applyEquality, 
functionExtensionality, 
setElimination, 
rename, 
natural_numberEquality, 
equalityTransitivity, 
functionEquality, 
universeEquality, 
isect_memberFormation, 
isect_memberEquality, 
axiomEquality, 
imageMemberEquality, 
baseClosed, 
independent_isectElimination, 
independent_functionElimination, 
lambdaFormation, 
dependent_functionElimination, 
dependent_set_memberEquality, 
independent_pairFormation
Latex:
\mforall{}[A,B:Type].  \mforall{}[b:bag(A)].  \mforall{}[f1,f2:A  {}\mrightarrow{}  bag(B)].
    \mcup{}x\mmember{}b.f1[x]  =  \mcup{}x\mmember{}b.f2[x]  supposing  \mforall{}x:\{x:A|  x  \mdownarrow{}\mmember{}  b\}  .  (f1[x]  =  f2[x])
Date html generated:
2017_10_01-AM-08_56_09
Last ObjectModification:
2017_07_26-PM-04_38_11
Theory : bags
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