Description: Restricted class abstraction with true formula. (Contributed by BJ, 22-Apr-2019)
Ref | Expression | ||
---|---|---|---|
Assertion | bj-rabtr | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ssrab2 | |
|
2 | ssid | |
|
3 | tru | |
|
4 | 3 | rgenw | |
5 | ssrab | |
|
6 | 2 4 5 | mpbir2an | |
7 | 1 6 | eqssi | |