| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 2zrng.e | ⊢ 𝐸  =  { 𝑧  ∈  ℤ  ∣  ∃ 𝑥  ∈  ℤ 𝑧  =  ( 2  ·  𝑥 ) } | 
						
							| 2 |  | 2zrngbas.r | ⊢ 𝑅  =  ( ℂfld  ↾s  𝐸 ) | 
						
							| 3 |  | cncrng | ⊢ ℂfld  ∈  CRing | 
						
							| 4 |  | crngring | ⊢ ( ℂfld  ∈  CRing  →  ℂfld  ∈  Ring ) | 
						
							| 5 |  | ringmnd | ⊢ ( ℂfld  ∈  Ring  →  ℂfld  ∈  Mnd ) | 
						
							| 6 | 3 4 5 | mp2b | ⊢ ℂfld  ∈  Mnd | 
						
							| 7 | 1 | 0even | ⊢ 0  ∈  𝐸 | 
						
							| 8 |  | ssrab2 | ⊢ { 𝑧  ∈  ℤ  ∣  ∃ 𝑥  ∈  ℤ 𝑧  =  ( 2  ·  𝑥 ) }  ⊆  ℤ | 
						
							| 9 | 1 8 | eqsstri | ⊢ 𝐸  ⊆  ℤ | 
						
							| 10 |  | zsscn | ⊢ ℤ  ⊆  ℂ | 
						
							| 11 | 9 10 | sstri | ⊢ 𝐸  ⊆  ℂ | 
						
							| 12 |  | cnfldbas | ⊢ ℂ  =  ( Base ‘ ℂfld ) | 
						
							| 13 |  | cnfld0 | ⊢ 0  =  ( 0g ‘ ℂfld ) | 
						
							| 14 | 2 12 13 | ress0g | ⊢ ( ( ℂfld  ∈  Mnd  ∧  0  ∈  𝐸  ∧  𝐸  ⊆  ℂ )  →  0  =  ( 0g ‘ 𝑅 ) ) | 
						
							| 15 | 6 7 11 14 | mp3an | ⊢ 0  =  ( 0g ‘ 𝑅 ) |