Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - start with the Axiom of Extensionality
Binary relations
breqd
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breq2d
Metamath Proof Explorer
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Unicode
Theorem
breqd
Description:
Equality deduction for a binary relation.
(Contributed by
NM
, 29-Oct-2011)
Ref
Expression
Hypothesis
breq1d.1
⊢
φ
→
A
=
B
Assertion
breqd
⊢
φ
→
C
A
D
↔
C
B
D
Proof
Step
Hyp
Ref
Expression
1
breq1d.1
⊢
φ
→
A
=
B
2
breq
⊢
A
=
B
→
C
A
D
↔
C
B
D
3
1
2
syl
⊢
φ
→
C
A
D
↔
C
B
D