| Step | Hyp | Ref | Expression | 
						
							| 0 |  | cdomn | ⊢ Domn | 
						
							| 1 |  | vr | ⊢ 𝑟 | 
						
							| 2 |  | cnzr | ⊢ NzRing | 
						
							| 3 |  | cbs | ⊢ Base | 
						
							| 4 | 1 | cv | ⊢ 𝑟 | 
						
							| 5 | 4 3 | cfv | ⊢ ( Base ‘ 𝑟 ) | 
						
							| 6 |  | vb | ⊢ 𝑏 | 
						
							| 7 |  | c0g | ⊢ 0g | 
						
							| 8 | 4 7 | cfv | ⊢ ( 0g ‘ 𝑟 ) | 
						
							| 9 |  | vz | ⊢ 𝑧 | 
						
							| 10 |  | vx | ⊢ 𝑥 | 
						
							| 11 | 6 | cv | ⊢ 𝑏 | 
						
							| 12 |  | vy | ⊢ 𝑦 | 
						
							| 13 | 10 | cv | ⊢ 𝑥 | 
						
							| 14 |  | cmulr | ⊢ .r | 
						
							| 15 | 4 14 | cfv | ⊢ ( .r ‘ 𝑟 ) | 
						
							| 16 | 12 | cv | ⊢ 𝑦 | 
						
							| 17 | 13 16 15 | co | ⊢ ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 ) | 
						
							| 18 | 9 | cv | ⊢ 𝑧 | 
						
							| 19 | 17 18 | wceq | ⊢ ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧 | 
						
							| 20 | 13 18 | wceq | ⊢ 𝑥  =  𝑧 | 
						
							| 21 | 16 18 | wceq | ⊢ 𝑦  =  𝑧 | 
						
							| 22 | 20 21 | wo | ⊢ ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) | 
						
							| 23 | 19 22 | wi | ⊢ ( ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧  →  ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) ) | 
						
							| 24 | 23 12 11 | wral | ⊢ ∀ 𝑦  ∈  𝑏 ( ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧  →  ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) ) | 
						
							| 25 | 24 10 11 | wral | ⊢ ∀ 𝑥  ∈  𝑏 ∀ 𝑦  ∈  𝑏 ( ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧  →  ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) ) | 
						
							| 26 | 25 9 8 | wsbc | ⊢ [ ( 0g ‘ 𝑟 )  /  𝑧 ] ∀ 𝑥  ∈  𝑏 ∀ 𝑦  ∈  𝑏 ( ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧  →  ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) ) | 
						
							| 27 | 26 6 5 | wsbc | ⊢ [ ( Base ‘ 𝑟 )  /  𝑏 ] [ ( 0g ‘ 𝑟 )  /  𝑧 ] ∀ 𝑥  ∈  𝑏 ∀ 𝑦  ∈  𝑏 ( ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧  →  ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) ) | 
						
							| 28 | 27 1 2 | crab | ⊢ { 𝑟  ∈  NzRing  ∣  [ ( Base ‘ 𝑟 )  /  𝑏 ] [ ( 0g ‘ 𝑟 )  /  𝑧 ] ∀ 𝑥  ∈  𝑏 ∀ 𝑦  ∈  𝑏 ( ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧  →  ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) ) } | 
						
							| 29 | 0 28 | wceq | ⊢ Domn  =  { 𝑟  ∈  NzRing  ∣  [ ( Base ‘ 𝑟 )  /  𝑏 ] [ ( 0g ‘ 𝑟 )  /  𝑧 ] ∀ 𝑥  ∈  𝑏 ∀ 𝑦  ∈  𝑏 ( ( 𝑥 ( .r ‘ 𝑟 ) 𝑦 )  =  𝑧  →  ( 𝑥  =  𝑧  ∨  𝑦  =  𝑧 ) ) } |