Metamath Proof Explorer
Description: Existence of the class of values of a set. (Contributed by NM, 9-Nov-1995)
|
|
Ref |
Expression |
|
Hypothesis |
fvclex.1 |
⊢ 𝐹 ∈ V |
|
Assertion |
fvclex |
⊢ { 𝑦 ∣ ∃ 𝑥 𝑦 = ( 𝐹 ‘ 𝑥 ) } ∈ V |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
fvclex.1 |
⊢ 𝐹 ∈ V |
2 |
1
|
rnex |
⊢ ran 𝐹 ∈ V |
3 |
|
snex |
⊢ { ∅ } ∈ V |
4 |
2 3
|
unex |
⊢ ( ran 𝐹 ∪ { ∅ } ) ∈ V |
5 |
|
fvclss |
⊢ { 𝑦 ∣ ∃ 𝑥 𝑦 = ( 𝐹 ‘ 𝑥 ) } ⊆ ( ran 𝐹 ∪ { ∅ } ) |
6 |
4 5
|
ssexi |
⊢ { 𝑦 ∣ ∃ 𝑥 𝑦 = ( 𝐹 ‘ 𝑥 ) } ∈ V |