Nuprl Lemma : set-image_wf2
∀[b:coSet{i:l}]. ∀[f:(x:coSet{i:l} × (x ∈ b)) ⟶ Set{i:l}].  (set-image(f;b) ∈ Set{i:l})
Proof
Definitions occuring in Statement : 
set-image: set-image(f;b)
, 
Set: Set{i:l}
, 
setmem: (x ∈ s)
, 
coSet: coSet{i:l}
, 
uall: ∀[x:A]. B[x]
, 
member: t ∈ T
, 
function: x:A ⟶ B[x]
, 
product: x:A × B[x]
Definitions unfolded in proof : 
so_apply: x[s]
, 
prop: ℙ
, 
mk-coset: mk-coset(T;f)
, 
Wsup: Wsup(a;b)
, 
mk-set: f"(T)
, 
so_lambda: λ2x.t[x]
, 
subtype_rel: A ⊆r B
, 
mkset: {f[t] | t ∈ T}
, 
set-image: set-image(f;b)
, 
member: t ∈ T
, 
uall: ∀[x:A]. B[x]
Lemmas referenced : 
Set_wf, 
coSet_wf, 
mk-coset_wf, 
setmem_wf, 
subtype_rel_self, 
mem-mk-set_wf2, 
mkset_wf, 
coSet_subtype, 
subtype_coSet
Rules used in proof : 
because_Cache, 
isect_memberEquality, 
cumulativity, 
productEquality, 
functionEquality, 
equalitySymmetry, 
equalityTransitivity, 
axiomEquality, 
dependent_pairEquality, 
lambdaEquality, 
isectElimination, 
thin, 
productElimination, 
sqequalHypSubstitution, 
applyEquality, 
hypothesisEquality, 
hypothesis, 
extract_by_obid, 
hypothesis_subsumption, 
sqequalRule, 
cut, 
introduction, 
isect_memberFormation, 
sqequalReflexivity, 
computationStep, 
sqequalTransitivity, 
sqequalSubstitution
Latex:
\mforall{}[b:coSet\{i:l\}].  \mforall{}[f:(x:coSet\{i:l\}  \mtimes{}  (x  \mmember{}  b))  {}\mrightarrow{}  Set\{i:l\}].    (set-image(f;b)  \mmember{}  Set\{i:l\})
Date html generated:
2018_07_29-AM-10_08_49
Last ObjectModification:
2018_07_18-PM-00_36_16
Theory : constructive!set!theory
Home
Index