Description: The additive identity of R is the complex number 0. (Contributed by AV, 11-Feb-2020)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | 2zrng.e | |- E = { z e. ZZ | E. x e. ZZ z = ( 2 x. x ) } | |
| 2zrngbas.r | |- R = ( CCfld |`s E ) | ||
| Assertion | 2zrng0 | |- 0 = ( 0g ` R ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | 2zrng.e |  |-  E = { z e. ZZ | E. x e. ZZ z = ( 2 x. x ) } | |
| 2 | 2zrngbas.r | |- R = ( CCfld |`s E ) | |
| 3 | cncrng | |- CCfld e. CRing | |
| 4 | crngring | |- ( CCfld e. CRing -> CCfld e. Ring ) | |
| 5 | ringmnd | |- ( CCfld e. Ring -> CCfld e. Mnd ) | |
| 6 | 3 4 5 | mp2b | |- CCfld e. Mnd | 
| 7 | 1 | 0even | |- 0 e. E | 
| 8 | ssrab2 |  |-  { z e. ZZ | E. x e. ZZ z = ( 2 x. x ) } C_ ZZ | |
| 9 | 1 8 | eqsstri | |- E C_ ZZ | 
| 10 | zsscn | |- ZZ C_ CC | |
| 11 | 9 10 | sstri | |- E C_ CC | 
| 12 | cnfldbas | |- CC = ( Base ` CCfld ) | |
| 13 | cnfld0 | |- 0 = ( 0g ` CCfld ) | |
| 14 | 2 12 13 | ress0g | |- ( ( CCfld e. Mnd /\ 0 e. E /\ E C_ CC ) -> 0 = ( 0g ` R ) ) | 
| 15 | 6 7 11 14 | mp3an | |- 0 = ( 0g ` R ) |