| Step | Hyp | Ref | Expression | 
						
							| 1 |  | pwsexpg.y | ⊢ 𝑌  =  ( 𝑅  ↑s  𝐼 ) | 
						
							| 2 |  | pwsexpg.b | ⊢ 𝐵  =  ( Base ‘ 𝑌 ) | 
						
							| 3 |  | pwsexpg.m | ⊢ 𝑀  =  ( mulGrp ‘ 𝑌 ) | 
						
							| 4 |  | pwsexpg.t | ⊢ 𝑇  =  ( mulGrp ‘ 𝑅 ) | 
						
							| 5 |  | pwsexpg.s | ⊢  ∙   =  ( .g ‘ 𝑀 ) | 
						
							| 6 |  | pwsexpg.g | ⊢  ·   =  ( .g ‘ 𝑇 ) | 
						
							| 7 |  | pwsexpg.r | ⊢ ( 𝜑  →  𝑅  ∈  Ring ) | 
						
							| 8 |  | pwsexpg.i | ⊢ ( 𝜑  →  𝐼  ∈  𝑉 ) | 
						
							| 9 |  | pwsexpg.n | ⊢ ( 𝜑  →  𝑁  ∈  ℕ0 ) | 
						
							| 10 |  | pwsexpg.x | ⊢ ( 𝜑  →  𝑋  ∈  𝐵 ) | 
						
							| 11 |  | pwsexpg.a | ⊢ ( 𝜑  →  𝐴  ∈  𝐼 ) | 
						
							| 12 | 1 2 3 4 7 8 11 | pwspjmhmmgpd | ⊢ ( 𝜑  →  ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) )  ∈  ( 𝑀  MndHom  𝑇 ) ) | 
						
							| 13 | 3 2 | mgpbas | ⊢ 𝐵  =  ( Base ‘ 𝑀 ) | 
						
							| 14 | 13 5 6 | mhmmulg | ⊢ ( ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) )  ∈  ( 𝑀  MndHom  𝑇 )  ∧  𝑁  ∈  ℕ0  ∧  𝑋  ∈  𝐵 )  →  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ ( 𝑁  ∙  𝑋 ) )  =  ( 𝑁  ·  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ 𝑋 ) ) ) | 
						
							| 15 | 12 9 10 14 | syl3anc | ⊢ ( 𝜑  →  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ ( 𝑁  ∙  𝑋 ) )  =  ( 𝑁  ·  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ 𝑋 ) ) ) | 
						
							| 16 | 1 | pwsring | ⊢ ( ( 𝑅  ∈  Ring  ∧  𝐼  ∈  𝑉 )  →  𝑌  ∈  Ring ) | 
						
							| 17 | 7 8 16 | syl2anc | ⊢ ( 𝜑  →  𝑌  ∈  Ring ) | 
						
							| 18 | 3 | ringmgp | ⊢ ( 𝑌  ∈  Ring  →  𝑀  ∈  Mnd ) | 
						
							| 19 | 17 18 | syl | ⊢ ( 𝜑  →  𝑀  ∈  Mnd ) | 
						
							| 20 | 13 5 19 9 10 | mulgnn0cld | ⊢ ( 𝜑  →  ( 𝑁  ∙  𝑋 )  ∈  𝐵 ) | 
						
							| 21 |  | fveq1 | ⊢ ( 𝑥  =  ( 𝑁  ∙  𝑋 )  →  ( 𝑥 ‘ 𝐴 )  =  ( ( 𝑁  ∙  𝑋 ) ‘ 𝐴 ) ) | 
						
							| 22 |  | eqid | ⊢ ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) )  =  ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) | 
						
							| 23 |  | fvex | ⊢ ( ( 𝑁  ∙  𝑋 ) ‘ 𝐴 )  ∈  V | 
						
							| 24 | 21 22 23 | fvmpt | ⊢ ( ( 𝑁  ∙  𝑋 )  ∈  𝐵  →  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ ( 𝑁  ∙  𝑋 ) )  =  ( ( 𝑁  ∙  𝑋 ) ‘ 𝐴 ) ) | 
						
							| 25 | 20 24 | syl | ⊢ ( 𝜑  →  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ ( 𝑁  ∙  𝑋 ) )  =  ( ( 𝑁  ∙  𝑋 ) ‘ 𝐴 ) ) | 
						
							| 26 |  | fveq1 | ⊢ ( 𝑥  =  𝑋  →  ( 𝑥 ‘ 𝐴 )  =  ( 𝑋 ‘ 𝐴 ) ) | 
						
							| 27 |  | fvex | ⊢ ( 𝑋 ‘ 𝐴 )  ∈  V | 
						
							| 28 | 26 22 27 | fvmpt | ⊢ ( 𝑋  ∈  𝐵  →  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ 𝑋 )  =  ( 𝑋 ‘ 𝐴 ) ) | 
						
							| 29 | 10 28 | syl | ⊢ ( 𝜑  →  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ 𝑋 )  =  ( 𝑋 ‘ 𝐴 ) ) | 
						
							| 30 | 29 | oveq2d | ⊢ ( 𝜑  →  ( 𝑁  ·  ( ( 𝑥  ∈  𝐵  ↦  ( 𝑥 ‘ 𝐴 ) ) ‘ 𝑋 ) )  =  ( 𝑁  ·  ( 𝑋 ‘ 𝐴 ) ) ) | 
						
							| 31 | 15 25 30 | 3eqtr3d | ⊢ ( 𝜑  →  ( ( 𝑁  ∙  𝑋 ) ‘ 𝐴 )  =  ( 𝑁  ·  ( 𝑋 ‘ 𝐴 ) ) ) |