Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Union
Infinite Cartesian products
elixp
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elixpconst
Metamath Proof Explorer
Ascii
Unicode
Theorem
elixp
Description:
Membership in an infinite Cartesian product.
(Contributed by
NM
, 28-Sep-2006)
Ref
Expression
Hypothesis
elixp.1
⊢
F
∈
V
Assertion
elixp
⊢
F
∈
⨉
x
∈
A
B
↔
F
Fn
A
∧
∀
x
∈
A
F
⁡
x
∈
B
Proof
Step
Hyp
Ref
Expression
1
elixp.1
⊢
F
∈
V
2
elixp2
⊢
F
∈
⨉
x
∈
A
B
↔
F
∈
V
∧
F
Fn
A
∧
∀
x
∈
A
F
⁡
x
∈
B
3
3anass
⊢
F
∈
V
∧
F
Fn
A
∧
∀
x
∈
A
F
⁡
x
∈
B
↔
F
∈
V
∧
F
Fn
A
∧
∀
x
∈
A
F
⁡
x
∈
B
4
1
3
mpbiran
⊢
F
∈
V
∧
F
Fn
A
∧
∀
x
∈
A
F
⁡
x
∈
B
↔
F
Fn
A
∧
∀
x
∈
A
F
⁡
x
∈
B
5
2
4
bitri
⊢
F
∈
⨉
x
∈
A
B
↔
F
Fn
A
∧
∀
x
∈
A
F
⁡
x
∈
B