Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Power Sets
Relations
relelrnb
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releldmi
Metamath Proof Explorer
Ascii
Unicode
Theorem
relelrnb
Description:
Membership in a range.
(Contributed by
Mario Carneiro
, 5-Nov-2015)
Ref
Expression
Assertion
relelrnb
⊢
Rel
⁡
R
→
A
∈
ran
⁡
R
↔
∃
x
x
R
A
Proof
Step
Hyp
Ref
Expression
1
elrng
⊢
A
∈
ran
⁡
R
→
A
∈
ran
⁡
R
↔
∃
x
x
R
A
2
1
ibi
⊢
A
∈
ran
⁡
R
→
∃
x
x
R
A
3
relelrn
⊢
Rel
⁡
R
∧
x
R
A
→
A
∈
ran
⁡
R
4
3
ex
⊢
Rel
⁡
R
→
x
R
A
→
A
∈
ran
⁡
R
5
4
exlimdv
⊢
Rel
⁡
R
→
∃
x
x
R
A
→
A
∈
ran
⁡
R
6
2
5
impbid2
⊢
Rel
⁡
R
→
A
∈
ran
⁡
R
↔
∃
x
x
R
A