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Description: The opposite of a nonzero ring is nonzero, bidirectional form of opprnzr . (Contributed by SN, 20-Jun-2025)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | opprnzr.1 | |- O = ( oppR ` R ) |
|
| Assertion | opprnzrb | |- ( R e. NzRing <-> O e. NzRing ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | opprnzr.1 | |- O = ( oppR ` R ) |
|
| 2 | 1 | opprringb | |- ( R e. Ring <-> O e. Ring ) |
| 3 | 2 | anbi1i | |- ( ( R e. Ring /\ ( 1r ` R ) =/= ( 0g ` R ) ) <-> ( O e. Ring /\ ( 1r ` R ) =/= ( 0g ` R ) ) ) |
| 4 | eqid | |- ( 1r ` R ) = ( 1r ` R ) |
|
| 5 | eqid | |- ( 0g ` R ) = ( 0g ` R ) |
|
| 6 | 4 5 | isnzr | |- ( R e. NzRing <-> ( R e. Ring /\ ( 1r ` R ) =/= ( 0g ` R ) ) ) |
| 7 | 1 4 | oppr1 | |- ( 1r ` R ) = ( 1r ` O ) |
| 8 | 1 5 | oppr0 | |- ( 0g ` R ) = ( 0g ` O ) |
| 9 | 7 8 | isnzr | |- ( O e. NzRing <-> ( O e. Ring /\ ( 1r ` R ) =/= ( 0g ` R ) ) ) |
| 10 | 3 6 9 | 3bitr4i | |- ( R e. NzRing <-> O e. NzRing ) |