Metamath Proof Explorer
Description: Example for df-eprel . Example by David A. Wheeler. (Contributed by Mario Carneiro, 18-Jun-2015)
|
|
Ref |
Expression |
|
Assertion |
ex-eprel |
|
Proof
| Step |
Hyp |
Ref |
Expression |
| 1 |
|
5nn |
|
| 2 |
1
|
elexi |
|
| 3 |
2
|
prid2 |
|
| 4 |
|
prex |
|
| 5 |
4
|
epeli |
|
| 6 |
3 5
|
mpbir |
|