Nuprl Lemma : equipollent-product-sum
∀[A:Type]. ∀[B:A ⟶ Type]. ∀[C:a:A ⟶ B[a] ⟶ Type].  x:A ⟶ (y:B[x] × C[x;y]) ~ f:a:A ⟶ B[a] × (x:A ⟶ C[x;f x])
Proof
Definitions occuring in Statement : 
equipollent: A ~ B
, 
uall: ∀[x:A]. B[x]
, 
so_apply: x[s1;s2]
, 
so_apply: x[s]
, 
apply: f a
, 
function: x:A ⟶ B[x]
, 
product: x:A × B[x]
, 
universe: Type
Definitions unfolded in proof : 
uall: ∀[x:A]. B[x]
, 
equipollent: A ~ B
, 
exists: ∃x:A. B[x]
, 
member: t ∈ T
, 
all: ∀x:A. B[x]
, 
implies: P 
⇒ Q
, 
so_apply: x[s1;s2]
, 
so_apply: x[s]
, 
prop: ℙ
, 
pi2: snd(t)
, 
subtype_rel: A ⊆r B
, 
so_lambda: λ2x.t[x]
, 
uimplies: b supposing a
, 
and: P ∧ Q
, 
pi1: fst(t)
, 
biject: Bij(A;B;f)
, 
inject: Inj(A;B;f)
, 
surject: Surj(A;B;f)
Lemmas referenced : 
equal_wf, 
subtype_rel-equal, 
pi1_wf, 
and_wf, 
biject_wf, 
subtype_rel_self, 
subtype_rel_wf
Rules used in proof : 
sqequalSubstitution, 
sqequalTransitivity, 
computationStep, 
sqequalReflexivity, 
isect_memberFormation, 
dependent_pairFormation, 
lambdaEquality, 
dependent_pairEquality, 
cut, 
because_Cache, 
thin, 
lambdaFormation, 
introduction, 
extract_by_obid, 
sqequalHypSubstitution, 
isectElimination, 
equalityTransitivity, 
hypothesis, 
equalitySymmetry, 
hypothesisEquality, 
sqequalRule, 
dependent_functionElimination, 
independent_functionElimination, 
cumulativity, 
productElimination, 
applyEquality, 
functionExtensionality, 
productEquality, 
independent_isectElimination, 
dependent_set_memberEquality, 
independent_pairFormation, 
applyLambdaEquality, 
setElimination, 
rename, 
functionEquality, 
universeEquality, 
hyp_replacement
Latex:
\mforall{}[A:Type].  \mforall{}[B:A  {}\mrightarrow{}  Type].  \mforall{}[C:a:A  {}\mrightarrow{}  B[a]  {}\mrightarrow{}  Type].
    x:A  {}\mrightarrow{}  (y:B[x]  \mtimes{}  C[x;y])  \msim{}  f:a:A  {}\mrightarrow{}  B[a]  \mtimes{}  (x:A  {}\mrightarrow{}  C[x;f  x])
Date html generated:
2017_04_17-AM-09_32_38
Last ObjectModification:
2017_02_27-PM-05_32_12
Theory : equipollence!!cardinality!
Home
Index