| Step | Hyp | Ref | Expression | 
						
							| 1 |  | rrxtopn.1 | ⊢ ( 𝜑  →  𝐼  ∈  𝑉 ) | 
						
							| 2 |  | eqid | ⊢ ( ℝ^ ‘ 𝐼 )  =  ( ℝ^ ‘ 𝐼 ) | 
						
							| 3 | 2 | rrxval | ⊢ ( 𝐼  ∈  𝑉  →  ( ℝ^ ‘ 𝐼 )  =  ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) | 
						
							| 4 | 1 3 | syl | ⊢ ( 𝜑  →  ( ℝ^ ‘ 𝐼 )  =  ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) | 
						
							| 5 | 4 | fveq2d | ⊢ ( 𝜑  →  ( TopOpen ‘ ( ℝ^ ‘ 𝐼 ) )  =  ( TopOpen ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) ) | 
						
							| 6 |  | ovex | ⊢ ( ℝfld  freeLMod  𝐼 )  ∈  V | 
						
							| 7 |  | eqid | ⊢ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) )  =  ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) | 
						
							| 8 |  | eqid | ⊢ ( dist ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) )  =  ( dist ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) | 
						
							| 9 |  | eqid | ⊢ ( TopOpen ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) )  =  ( TopOpen ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) | 
						
							| 10 | 7 8 9 | tcphtopn | ⊢ ( ( ℝfld  freeLMod  𝐼 )  ∈  V  →  ( TopOpen ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) )  =  ( MetOpen ‘ ( dist ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) ) ) | 
						
							| 11 | 6 10 | ax-mp | ⊢ ( TopOpen ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) )  =  ( MetOpen ‘ ( dist ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) ) | 
						
							| 12 | 11 | a1i | ⊢ ( 𝜑  →  ( TopOpen ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) )  =  ( MetOpen ‘ ( dist ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) ) ) | 
						
							| 13 | 4 | eqcomd | ⊢ ( 𝜑  →  ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) )  =  ( ℝ^ ‘ 𝐼 ) ) | 
						
							| 14 | 13 | fveq2d | ⊢ ( 𝜑  →  ( dist ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) )  =  ( dist ‘ ( ℝ^ ‘ 𝐼 ) ) ) | 
						
							| 15 | 14 | fveq2d | ⊢ ( 𝜑  →  ( MetOpen ‘ ( dist ‘ ( toℂPreHil ‘ ( ℝfld  freeLMod  𝐼 ) ) ) )  =  ( MetOpen ‘ ( dist ‘ ( ℝ^ ‘ 𝐼 ) ) ) ) | 
						
							| 16 | 5 12 15 | 3eqtrd | ⊢ ( 𝜑  →  ( TopOpen ‘ ( ℝ^ ‘ 𝐼 ) )  =  ( MetOpen ‘ ( dist ‘ ( ℝ^ ‘ 𝐼 ) ) ) ) | 
						
							| 17 |  | eqid | ⊢ ( Base ‘ ( ℝ^ ‘ 𝐼 ) )  =  ( Base ‘ ( ℝ^ ‘ 𝐼 ) ) | 
						
							| 18 | 2 17 | rrxds | ⊢ ( 𝐼  ∈  𝑉  →  ( 𝑓  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) ) ,  𝑔  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) )  ↦  ( √ ‘ ( ℝfld  Σg  ( 𝑥  ∈  𝐼  ↦  ( ( ( 𝑓 ‘ 𝑥 )  −  ( 𝑔 ‘ 𝑥 ) ) ↑ 2 ) ) ) ) )  =  ( dist ‘ ( ℝ^ ‘ 𝐼 ) ) ) | 
						
							| 19 | 1 18 | syl | ⊢ ( 𝜑  →  ( 𝑓  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) ) ,  𝑔  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) )  ↦  ( √ ‘ ( ℝfld  Σg  ( 𝑥  ∈  𝐼  ↦  ( ( ( 𝑓 ‘ 𝑥 )  −  ( 𝑔 ‘ 𝑥 ) ) ↑ 2 ) ) ) ) )  =  ( dist ‘ ( ℝ^ ‘ 𝐼 ) ) ) | 
						
							| 20 | 19 | eqcomd | ⊢ ( 𝜑  →  ( dist ‘ ( ℝ^ ‘ 𝐼 ) )  =  ( 𝑓  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) ) ,  𝑔  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) )  ↦  ( √ ‘ ( ℝfld  Σg  ( 𝑥  ∈  𝐼  ↦  ( ( ( 𝑓 ‘ 𝑥 )  −  ( 𝑔 ‘ 𝑥 ) ) ↑ 2 ) ) ) ) ) ) | 
						
							| 21 | 20 | fveq2d | ⊢ ( 𝜑  →  ( MetOpen ‘ ( dist ‘ ( ℝ^ ‘ 𝐼 ) ) )  =  ( MetOpen ‘ ( 𝑓  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) ) ,  𝑔  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) )  ↦  ( √ ‘ ( ℝfld  Σg  ( 𝑥  ∈  𝐼  ↦  ( ( ( 𝑓 ‘ 𝑥 )  −  ( 𝑔 ‘ 𝑥 ) ) ↑ 2 ) ) ) ) ) ) ) | 
						
							| 22 | 16 21 | eqtrd | ⊢ ( 𝜑  →  ( TopOpen ‘ ( ℝ^ ‘ 𝐼 ) )  =  ( MetOpen ‘ ( 𝑓  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) ) ,  𝑔  ∈  ( Base ‘ ( ℝ^ ‘ 𝐼 ) )  ↦  ( √ ‘ ( ℝfld  Σg  ( 𝑥  ∈  𝐼  ↦  ( ( ( 𝑓 ‘ 𝑥 )  −  ( 𝑔 ‘ 𝑥 ) ) ↑ 2 ) ) ) ) ) ) ) |