Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Union
The mapping operation
elmapfn
Next ⟩
elmapfun
Metamath Proof Explorer
Ascii
Unicode
Theorem
elmapfn
Description:
A mapping is a function with the appropriate domain.
(Contributed by
AV
, 6-Apr-2019)
Ref
Expression
Assertion
elmapfn
⊢
A
∈
B
C
→
A
Fn
C
Proof
Step
Hyp
Ref
Expression
1
elmapi
⊢
A
∈
B
C
→
A
:
C
⟶
B
2
1
ffnd
⊢
A
∈
B
C
→
A
Fn
C