Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Union
Equinumerosity
brdom
Next ⟩
domen
Metamath Proof Explorer
Ascii
Unicode
Theorem
brdom
Description:
Dominance relation.
(Contributed by
NM
, 15-Jun-1998)
Ref
Expression
Hypothesis
bren.1
⊢
B
∈
V
Assertion
brdom
⊢
A
≼
B
↔
∃
f
f
:
A
⟶
1-1
B
Proof
Step
Hyp
Ref
Expression
1
bren.1
⊢
B
∈
V
2
brdomg
⊢
B
∈
V
→
A
≼
B
↔
∃
f
f
:
A
⟶
1-1
B
3
1
2
ax-mp
⊢
A
≼
B
↔
∃
f
f
:
A
⟶
1-1
B