Description: Identity law for subtraction. (Contributed by Scott Fenton, 3-Feb-2025)
Ref | Expression | ||
---|---|---|---|
Assertion | subsid1 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 0sno | ||
2 | subsval | ||
3 | 1 2 | mpan2 | |
4 | negs0s | ||
5 | 4 | oveq2i | |
6 | addsrid | ||
7 | 5 6 | eqtrid | |
8 | 3 7 | eqtrd |