| Step | Hyp | Ref | Expression | 
						
							| 0 |  | cmgmhm | ⊢  MgmHom | 
						
							| 1 |  | vs | ⊢ 𝑠 | 
						
							| 2 |  | cmgm | ⊢ Mgm | 
						
							| 3 |  | vt | ⊢ 𝑡 | 
						
							| 4 |  | vf | ⊢ 𝑓 | 
						
							| 5 |  | cbs | ⊢ Base | 
						
							| 6 | 3 | cv | ⊢ 𝑡 | 
						
							| 7 | 6 5 | cfv | ⊢ ( Base ‘ 𝑡 ) | 
						
							| 8 |  | cmap | ⊢  ↑m | 
						
							| 9 | 1 | cv | ⊢ 𝑠 | 
						
							| 10 | 9 5 | cfv | ⊢ ( Base ‘ 𝑠 ) | 
						
							| 11 | 7 10 8 | co | ⊢ ( ( Base ‘ 𝑡 )  ↑m  ( Base ‘ 𝑠 ) ) | 
						
							| 12 |  | vx | ⊢ 𝑥 | 
						
							| 13 |  | vy | ⊢ 𝑦 | 
						
							| 14 | 4 | cv | ⊢ 𝑓 | 
						
							| 15 | 12 | cv | ⊢ 𝑥 | 
						
							| 16 |  | cplusg | ⊢ +g | 
						
							| 17 | 9 16 | cfv | ⊢ ( +g ‘ 𝑠 ) | 
						
							| 18 | 13 | cv | ⊢ 𝑦 | 
						
							| 19 | 15 18 17 | co | ⊢ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) | 
						
							| 20 | 19 14 | cfv | ⊢ ( 𝑓 ‘ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) ) | 
						
							| 21 | 15 14 | cfv | ⊢ ( 𝑓 ‘ 𝑥 ) | 
						
							| 22 | 6 16 | cfv | ⊢ ( +g ‘ 𝑡 ) | 
						
							| 23 | 18 14 | cfv | ⊢ ( 𝑓 ‘ 𝑦 ) | 
						
							| 24 | 21 23 22 | co | ⊢ ( ( 𝑓 ‘ 𝑥 ) ( +g ‘ 𝑡 ) ( 𝑓 ‘ 𝑦 ) ) | 
						
							| 25 | 20 24 | wceq | ⊢ ( 𝑓 ‘ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) )  =  ( ( 𝑓 ‘ 𝑥 ) ( +g ‘ 𝑡 ) ( 𝑓 ‘ 𝑦 ) ) | 
						
							| 26 | 25 13 10 | wral | ⊢ ∀ 𝑦  ∈  ( Base ‘ 𝑠 ) ( 𝑓 ‘ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) )  =  ( ( 𝑓 ‘ 𝑥 ) ( +g ‘ 𝑡 ) ( 𝑓 ‘ 𝑦 ) ) | 
						
							| 27 | 26 12 10 | wral | ⊢ ∀ 𝑥  ∈  ( Base ‘ 𝑠 ) ∀ 𝑦  ∈  ( Base ‘ 𝑠 ) ( 𝑓 ‘ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) )  =  ( ( 𝑓 ‘ 𝑥 ) ( +g ‘ 𝑡 ) ( 𝑓 ‘ 𝑦 ) ) | 
						
							| 28 | 27 4 11 | crab | ⊢ { 𝑓  ∈  ( ( Base ‘ 𝑡 )  ↑m  ( Base ‘ 𝑠 ) )  ∣  ∀ 𝑥  ∈  ( Base ‘ 𝑠 ) ∀ 𝑦  ∈  ( Base ‘ 𝑠 ) ( 𝑓 ‘ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) )  =  ( ( 𝑓 ‘ 𝑥 ) ( +g ‘ 𝑡 ) ( 𝑓 ‘ 𝑦 ) ) } | 
						
							| 29 | 1 3 2 2 28 | cmpo | ⊢ ( 𝑠  ∈  Mgm ,  𝑡  ∈  Mgm  ↦  { 𝑓  ∈  ( ( Base ‘ 𝑡 )  ↑m  ( Base ‘ 𝑠 ) )  ∣  ∀ 𝑥  ∈  ( Base ‘ 𝑠 ) ∀ 𝑦  ∈  ( Base ‘ 𝑠 ) ( 𝑓 ‘ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) )  =  ( ( 𝑓 ‘ 𝑥 ) ( +g ‘ 𝑡 ) ( 𝑓 ‘ 𝑦 ) ) } ) | 
						
							| 30 | 0 29 | wceq | ⊢  MgmHom   =  ( 𝑠  ∈  Mgm ,  𝑡  ∈  Mgm  ↦  { 𝑓  ∈  ( ( Base ‘ 𝑡 )  ↑m  ( Base ‘ 𝑠 ) )  ∣  ∀ 𝑥  ∈  ( Base ‘ 𝑠 ) ∀ 𝑦  ∈  ( Base ‘ 𝑠 ) ( 𝑓 ‘ ( 𝑥 ( +g ‘ 𝑠 ) 𝑦 ) )  =  ( ( 𝑓 ‘ 𝑥 ) ( +g ‘ 𝑡 ) ( 𝑓 ‘ 𝑦 ) ) } ) |