Metamath Proof Explorer


Theorem relexp0rel

Description: The exponentiation of a class to zero is a relation. (Contributed by RP, 23-May-2020)

Ref Expression
Assertion relexp0rel ( 𝑅 ∈ 𝑉 → Rel ( 𝑅 ↑𝑟 0 ) )

Proof

Step Hyp Ref Expression
1 relres ⊢ Rel ( I ↾ ( dom 𝑅 ∪ ran 𝑅 ) )
2 relexp0g ⊢ ( 𝑅 ∈ 𝑉 → ( 𝑅 ↑𝑟 0 ) = ( I ↾ ( dom 𝑅 ∪ ran 𝑅 ) ) )
3 2 releqd ⊢ ( 𝑅 ∈ 𝑉 → ( Rel ( 𝑅 ↑𝑟 0 ) ↔ Rel ( I ↾ ( dom 𝑅 ∪ ran 𝑅 ) ) ) )
4 1 3 mpbiri ⊢ ( 𝑅 ∈ 𝑉 → Rel ( 𝑅 ↑𝑟 0 ) )