Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Power Sets
Operations
oprab4
Next ⟩
cbvoprab1
Metamath Proof Explorer
Ascii
Unicode
Theorem
oprab4
Description:
Two ways to state the domain of an operation.
(Contributed by
FL
, 24-Jan-2010)
Ref
Expression
Assertion
oprab4
⊢
x
y
z
|
x
y
∈
A
×
B
∧
φ
=
x
y
z
|
x
∈
A
∧
y
∈
B
∧
φ
Proof
Step
Hyp
Ref
Expression
1
opelxp
⊢
x
y
∈
A
×
B
↔
x
∈
A
∧
y
∈
B
2
1
anbi1i
⊢
x
y
∈
A
×
B
∧
φ
↔
x
∈
A
∧
y
∈
B
∧
φ
3
2
oprabbii
⊢
x
y
z
|
x
y
∈
A
×
B
∧
φ
=
x
y
z
|
x
∈
A
∧
y
∈
B
∧
φ