| Step | Hyp | Ref | Expression | 
						
							| 1 |  | idmatidpmat.t | ⊢ 𝑇  =  ( 𝑁  matToPolyMat  𝑅 ) | 
						
							| 2 |  | idmatidpmat.p | ⊢ 𝑃  =  ( Poly1 ‘ 𝑅 ) | 
						
							| 3 |  | 0mat2pmat.0 | ⊢  0   =  ( 0g ‘ ( 𝑁  Mat  𝑅 ) ) | 
						
							| 4 |  | 0mat2pmat.z | ⊢ 𝑍  =  ( 0g ‘ ( 𝑁  Mat  𝑃 ) ) | 
						
							| 5 |  | eqid | ⊢ ( 𝑁  Mat  𝑅 )  =  ( 𝑁  Mat  𝑅 ) | 
						
							| 6 |  | eqid | ⊢ ( Base ‘ ( 𝑁  Mat  𝑅 ) )  =  ( Base ‘ ( 𝑁  Mat  𝑅 ) ) | 
						
							| 7 |  | eqid | ⊢ ( 𝑁  Mat  𝑃 )  =  ( 𝑁  Mat  𝑃 ) | 
						
							| 8 |  | eqid | ⊢ ( Base ‘ ( 𝑁  Mat  𝑃 ) )  =  ( Base ‘ ( 𝑁  Mat  𝑃 ) ) | 
						
							| 9 | 1 5 6 2 7 8 | mat2pmatghm | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  𝑇  ∈  ( ( 𝑁  Mat  𝑅 )  GrpHom  ( 𝑁  Mat  𝑃 ) ) ) | 
						
							| 10 | 9 | ancoms | ⊢ ( ( 𝑅  ∈  Ring  ∧  𝑁  ∈  Fin )  →  𝑇  ∈  ( ( 𝑁  Mat  𝑅 )  GrpHom  ( 𝑁  Mat  𝑃 ) ) ) | 
						
							| 11 | 3 4 | ghmid | ⊢ ( 𝑇  ∈  ( ( 𝑁  Mat  𝑅 )  GrpHom  ( 𝑁  Mat  𝑃 ) )  →  ( 𝑇 ‘  0  )  =  𝑍 ) | 
						
							| 12 | 10 11 | syl | ⊢ ( ( 𝑅  ∈  Ring  ∧  𝑁  ∈  Fin )  →  ( 𝑇 ‘  0  )  =  𝑍 ) |