Metamath Proof Explorer
Description: Special case of bj-restsn , bj-restsnss , and bj-rest10 .
(Contributed by BJ, 27-Apr-2021)
|
|
Ref |
Expression |
|
Assertion |
bj-restsn10 |
⊢ ( 𝑋 ∈ 𝑉 → ( { 𝑋 } ↾t ∅ ) = { ∅ } ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
0ss |
⊢ ∅ ⊆ 𝑋 |
2 |
|
bj-restsnss |
⊢ ( ( 𝑋 ∈ 𝑉 ∧ ∅ ⊆ 𝑋 ) → ( { 𝑋 } ↾t ∅ ) = { ∅ } ) |
3 |
1 2
|
mpan2 |
⊢ ( 𝑋 ∈ 𝑉 → ( { 𝑋 } ↾t ∅ ) = { ∅ } ) |