Description: A chained subclass and equality deduction. (Contributed by Mario Carneiro, 2-Jan-2017)
Ref | Expression | ||
---|---|---|---|
Hypotheses | eqsstrdi.1 | |
|
eqsstrdi.2 | |
||
Assertion | eqsstrdi | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eqsstrdi.1 | |
|
2 | eqsstrdi.2 | |
|
3 | 2 | a1i | |
4 | 1 3 | eqsstrd | |