Metamath Proof Explorer
Description: Membership of second member of an ordered pair in a range. (Contributed by NM, 23-Feb-1997)
|
|
Ref |
Expression |
|
Hypotheses |
brelrn.1 |
|
|
|
brelrn.2 |
|
|
Assertion |
opelrn |
|
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
brelrn.1 |
|
2 |
|
brelrn.2 |
|
3 |
|
df-br |
|
4 |
1 2
|
brelrn |
|
5 |
3 4
|
sylbir |
|