Description: Elementhood in the class of disjoints. (Contributed by Peter Mazsa, 5-Sep-2021)
Ref | Expression | ||
---|---|---|---|
Assertion | eldisjs2 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eldisjs | ||
2 | cosscnvelrels | ||
3 | 2 | biantrud | |
4 | cosselcnvrefrels2 | ||
5 | 3 4 | syl6rbbr | |
6 | 5 | pm5.32ri | |
7 | 1 6 | bitri |