| Step | Hyp | Ref | Expression | 
						
							| 1 |  | m2cpmfo.s | ⊢ 𝑆  =  ( 𝑁  ConstPolyMat  𝑅 ) | 
						
							| 2 |  | m2cpmfo.t | ⊢ 𝑇  =  ( 𝑁  matToPolyMat  𝑅 ) | 
						
							| 3 |  | m2cpmfo.a | ⊢ 𝐴  =  ( 𝑁  Mat  𝑅 ) | 
						
							| 4 |  | m2cpmfo.k | ⊢ 𝐾  =  ( Base ‘ 𝐴 ) | 
						
							| 5 |  | m2cpmrngiso.p | ⊢ 𝑃  =  ( Poly1 ‘ 𝑅 ) | 
						
							| 6 |  | m2cpmrngiso.c | ⊢ 𝐶  =  ( 𝑁  Mat  𝑃 ) | 
						
							| 7 |  | m2cpmrngiso.u | ⊢ 𝑈  =  ( 𝐶  ↾s  𝑆 ) | 
						
							| 8 | 1 2 3 4 5 6 7 | m2cpmrhm | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing )  →  𝑇  ∈  ( 𝐴  RingHom  𝑈 ) ) | 
						
							| 9 |  | crngring | ⊢ ( 𝑅  ∈  CRing  →  𝑅  ∈  Ring ) | 
						
							| 10 | 1 2 3 4 | m2cpmf1o | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  𝑇 : 𝐾 –1-1-onto→ 𝑆 ) | 
						
							| 11 |  | eqid | ⊢ ( Base ‘ 𝐶 )  =  ( Base ‘ 𝐶 ) | 
						
							| 12 | 1 5 6 11 | cpmatpmat | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring  ∧  𝑚  ∈  𝑆 )  →  𝑚  ∈  ( Base ‘ 𝐶 ) ) | 
						
							| 13 | 12 | 3expia | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  ( 𝑚  ∈  𝑆  →  𝑚  ∈  ( Base ‘ 𝐶 ) ) ) | 
						
							| 14 | 13 | ssrdv | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  𝑆  ⊆  ( Base ‘ 𝐶 ) ) | 
						
							| 15 | 7 11 | ressbas2 | ⊢ ( 𝑆  ⊆  ( Base ‘ 𝐶 )  →  𝑆  =  ( Base ‘ 𝑈 ) ) | 
						
							| 16 | 14 15 | syl | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  𝑆  =  ( Base ‘ 𝑈 ) ) | 
						
							| 17 | 16 | eqcomd | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  ( Base ‘ 𝑈 )  =  𝑆 ) | 
						
							| 18 | 17 | f1oeq3d | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  ( 𝑇 : 𝐾 –1-1-onto→ ( Base ‘ 𝑈 )  ↔  𝑇 : 𝐾 –1-1-onto→ 𝑆 ) ) | 
						
							| 19 | 10 18 | mpbird | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  Ring )  →  𝑇 : 𝐾 –1-1-onto→ ( Base ‘ 𝑈 ) ) | 
						
							| 20 | 9 19 | sylan2 | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing )  →  𝑇 : 𝐾 –1-1-onto→ ( Base ‘ 𝑈 ) ) | 
						
							| 21 |  | eqid | ⊢ ( Base ‘ 𝑈 )  =  ( Base ‘ 𝑈 ) | 
						
							| 22 | 4 21 | isrim | ⊢ ( 𝑇  ∈  ( 𝐴  RingIso  𝑈 )  ↔  ( 𝑇  ∈  ( 𝐴  RingHom  𝑈 )  ∧  𝑇 : 𝐾 –1-1-onto→ ( Base ‘ 𝑈 ) ) ) | 
						
							| 23 | 8 20 22 | sylanbrc | ⊢ ( ( 𝑁  ∈  Fin  ∧  𝑅  ∈  CRing )  →  𝑇  ∈  ( 𝐴  RingIso  𝑈 ) ) |