Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Power Sets
Functions
frn
Next ⟩
frnd
Metamath Proof Explorer
Ascii
Structured
Theorem
frn
Description:
The range of a mapping.
(Contributed by
NM
, 3-Aug-1994)
Ref
Expression
Assertion
frn
⊢
(
𝐹
:
𝐴
⟶
𝐵
→ ran
𝐹
⊆
𝐵
)
Proof
Step
Hyp
Ref
Expression
1
df-f
⊢
(
𝐹
:
𝐴
⟶
𝐵
↔ (
𝐹
Fn
𝐴
∧ ran
𝐹
⊆
𝐵
) )
2
1
simprbi
⊢
(
𝐹
:
𝐴
⟶
𝐵
→ ran
𝐹
⊆
𝐵
)