Description: The opposite of a nonzero ring is nonzero, bidirectional form of opprnzr . (Contributed by SN, 20-Jun-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | opprnzr.1 | ||
| Assertion | opprnzrb | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | opprnzr.1 | ||
| 2 | 1 | opprringb | |
| 3 | 2 | anbi1i | |
| 4 | eqid | ||
| 5 | eqid | ||
| 6 | 4 5 | isnzr | |
| 7 | 1 4 | oppr1 | |
| 8 | 1 5 | oppr0 | |
| 9 | 7 8 | isnzr | |
| 10 | 3 6 9 | 3bitr4i |