Description: Codomain of the identity arrow. (Contributed by Mario Carneiro, 11-Jan-2017)
Ref | Expression | ||
---|---|---|---|
Hypotheses | idafval.i | ||
idafval.b | |||
idafval.c | |||
idahom.x | |||
Assertion | idacd |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | idafval.i | ||
2 | idafval.b | ||
3 | idafval.c | ||
4 | idahom.x | ||
5 | eqid | ||
6 | 1 2 3 4 5 | idahom | |
7 | 5 | homacd | |
8 | 6 7 | syl |