Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - start with the Axiom of Extensionality
Indexed union and intersection
elriin
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riin0
Metamath Proof Explorer
Ascii
Unicode
Theorem
elriin
Description:
Elementhood in a relative intersection.
(Contributed by
Mario Carneiro
, 30-Dec-2016)
Ref
Expression
Assertion
elriin
⊢
B
∈
A
∩
⋂
x
∈
X
S
↔
B
∈
A
∧
∀
x
∈
X
B
∈
S
Proof
Step
Hyp
Ref
Expression
1
elin
⊢
B
∈
A
∩
⋂
x
∈
X
S
↔
B
∈
A
∧
B
∈
⋂
x
∈
X
S
2
eliin
⊢
B
∈
A
→
B
∈
⋂
x
∈
X
S
↔
∀
x
∈
X
B
∈
S
3
2
pm5.32i
⊢
B
∈
A
∧
B
∈
⋂
x
∈
X
S
↔
B
∈
A
∧
∀
x
∈
X
B
∈
S
4
1
3
bitri
⊢
B
∈
A
∩
⋂
x
∈
X
S
↔
B
∈
A
∧
∀
x
∈
X
B
∈
S