Database
REAL AND COMPLEX NUMBERS
Reflexive and transitive closures of relations
Basic properties of closures
cleq1lem
Next ⟩
cleq1
Metamath Proof Explorer
Ascii
Unicode
Theorem
cleq1lem
Description:
Equality implies bijection.
(Contributed by
RP
, 9-May-2020)
Ref
Expression
Assertion
cleq1lem
⊢
A
=
B
→
A
⊆
C
∧
φ
↔
B
⊆
C
∧
φ
Proof
Step
Hyp
Ref
Expression
1
sseq1
⊢
A
=
B
→
A
⊆
C
↔
B
⊆
C
2
1
anbi1d
⊢
A
=
B
→
A
⊆
C
∧
φ
↔
B
⊆
C
∧
φ