Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Power Sets
Founded and well-ordering relations
nfse
Metamath Proof Explorer
Description: Bound-variable hypothesis builder for set-like relations. (Contributed by Mario Carneiro , 24-Jun-2015) (Revised by Mario Carneiro , 14-Oct-2016)
Ref
Expression
Hypotheses
nffr.r
⊢ Ⅎ _ x R
nffr.a
⊢ Ⅎ _ x A
Assertion
nfse
⊢ Ⅎ x R Se A
Proof
Step
Hyp
Ref
Expression
1
nffr.r
⊢ Ⅎ _ x R
2
nffr.a
⊢ Ⅎ _ x A
3
df-se
⊢ R Se A ↔ ∀ b ∈ A a ∈ A | a R b ∈ V
4
nfcv
⊢ Ⅎ _ x a
5
nfcv
⊢ Ⅎ _ x b
6
4 1 5
nfbr
⊢ Ⅎ x a R b
7
6 2
nfrabw
⊢ Ⅎ _ x a ∈ A | a R b
8
7
nfel1
⊢ Ⅎ x a ∈ A | a R b ∈ V
9
2 8
nfralw
⊢ Ⅎ x ∀ b ∈ A a ∈ A | a R b ∈ V
10
3 9
nfxfr
⊢ Ⅎ x R Se A