| Step | Hyp | Ref | Expression | 
						
							| 1 |  | zlmodzxz.z | ⊢ 𝑍  =  ( ℤring  freeLMod  { 0 ,  1 } ) | 
						
							| 2 |  | zlmodzxz.o | ⊢  0   =  { 〈 0 ,  0 〉 ,  〈 1 ,  0 〉 } | 
						
							| 3 |  | c0ex | ⊢ 0  ∈  V | 
						
							| 4 |  | 1ex | ⊢ 1  ∈  V | 
						
							| 5 |  | xpprsng | ⊢ ( ( 0  ∈  V  ∧  1  ∈  V  ∧  0  ∈  V )  →  ( { 0 ,  1 }  ×  { 0 } )  =  { 〈 0 ,  0 〉 ,  〈 1 ,  0 〉 } ) | 
						
							| 6 | 3 4 3 5 | mp3an | ⊢ ( { 0 ,  1 }  ×  { 0 } )  =  { 〈 0 ,  0 〉 ,  〈 1 ,  0 〉 } | 
						
							| 7 |  | zringring | ⊢ ℤring  ∈  Ring | 
						
							| 8 |  | prex | ⊢ { 0 ,  1 }  ∈  V | 
						
							| 9 |  | zring0 | ⊢ 0  =  ( 0g ‘ ℤring ) | 
						
							| 10 | 1 9 | frlm0 | ⊢ ( ( ℤring  ∈  Ring  ∧  { 0 ,  1 }  ∈  V )  →  ( { 0 ,  1 }  ×  { 0 } )  =  ( 0g ‘ 𝑍 ) ) | 
						
							| 11 | 7 8 10 | mp2an | ⊢ ( { 0 ,  1 }  ×  { 0 } )  =  ( 0g ‘ 𝑍 ) | 
						
							| 12 | 2 6 11 | 3eqtr2i | ⊢  0   =  ( 0g ‘ 𝑍 ) |