Description: An equality deduction for the subclass relationship. (Contributed by NM, 14-Aug-1994)
Ref | Expression | ||
---|---|---|---|
Hypothesis | sseq1d.1 | |
|
Assertion | sseq1d | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sseq1d.1 | |
|
2 | sseq1 | |
|
3 | 1 2 | syl | |