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fnimafnex
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Theorem
fnimafnex
Description:
The functional image of a function value exists.
(Contributed by
RP
, 31-Oct-2024)
Ref
Expression
Hypothesis
fnimafnex.f
⊢
F
Fn
B
Assertion
fnimafnex
⊢
F
G
⁡
A
∈
V
Proof
Step
Hyp
Ref
Expression
1
fnimafnex.f
⊢
F
Fn
B
2
fnfun
⊢
F
Fn
B
→
Fun
⁡
F
3
1
2
ax-mp
⊢
Fun
⁡
F
4
fvex
⊢
G
⁡
A
∈
V
5
funimaexg
⊢
Fun
⁡
F
∧
G
⁡
A
∈
V
→
F
G
⁡
A
∈
V
6
3
4
5
mp2an
⊢
F
G
⁡
A
∈
V