Description: A set is a subset of its image under the identity relation. (Contributed by RP, 22-Jul-2020)
Ref | Expression | ||
---|---|---|---|
Hypothesis | fvilbd.r | ||
Assertion | fvilbd |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | fvilbd.r | ||
2 | ssid | ||
3 | fvi | ||
4 | 1 3 | syl | |
5 | 2 4 | sseqtrrid |