| Step | Hyp | Ref | Expression | 
						
							| 1 |  | pi1grp.2 | ⊢ 𝐺  =  ( 𝐽  π1  𝑌 ) | 
						
							| 2 |  | pi1inv.n | ⊢ 𝑁  =  ( invg ‘ 𝐺 ) | 
						
							| 3 |  | pi1inv.j | ⊢ ( 𝜑  →  𝐽  ∈  ( TopOn ‘ 𝑋 ) ) | 
						
							| 4 |  | pi1inv.y | ⊢ ( 𝜑  →  𝑌  ∈  𝑋 ) | 
						
							| 5 |  | pi1inv.f | ⊢ ( 𝜑  →  𝐹  ∈  ( II  Cn  𝐽 ) ) | 
						
							| 6 |  | pi1inv.0 | ⊢ ( 𝜑  →  ( 𝐹 ‘ 0 )  =  𝑌 ) | 
						
							| 7 |  | pi1inv.1 | ⊢ ( 𝜑  →  ( 𝐹 ‘ 1 )  =  𝑌 ) | 
						
							| 8 |  | pi1inv.i | ⊢ 𝐼  =  ( 𝑥  ∈  ( 0 [,] 1 )  ↦  ( 𝐹 ‘ ( 1  −  𝑥 ) ) ) | 
						
							| 9 |  | eqid | ⊢ ( Base ‘ 𝐺 )  =  ( Base ‘ 𝐺 ) | 
						
							| 10 |  | eqid | ⊢ ( +g ‘ 𝐺 )  =  ( +g ‘ 𝐺 ) | 
						
							| 11 | 8 | pcorevcl | ⊢ ( 𝐹  ∈  ( II  Cn  𝐽 )  →  ( 𝐼  ∈  ( II  Cn  𝐽 )  ∧  ( 𝐼 ‘ 0 )  =  ( 𝐹 ‘ 1 )  ∧  ( 𝐼 ‘ 1 )  =  ( 𝐹 ‘ 0 ) ) ) | 
						
							| 12 | 5 11 | syl | ⊢ ( 𝜑  →  ( 𝐼  ∈  ( II  Cn  𝐽 )  ∧  ( 𝐼 ‘ 0 )  =  ( 𝐹 ‘ 1 )  ∧  ( 𝐼 ‘ 1 )  =  ( 𝐹 ‘ 0 ) ) ) | 
						
							| 13 | 12 | simp1d | ⊢ ( 𝜑  →  𝐼  ∈  ( II  Cn  𝐽 ) ) | 
						
							| 14 | 12 | simp2d | ⊢ ( 𝜑  →  ( 𝐼 ‘ 0 )  =  ( 𝐹 ‘ 1 ) ) | 
						
							| 15 | 14 7 | eqtrd | ⊢ ( 𝜑  →  ( 𝐼 ‘ 0 )  =  𝑌 ) | 
						
							| 16 | 12 | simp3d | ⊢ ( 𝜑  →  ( 𝐼 ‘ 1 )  =  ( 𝐹 ‘ 0 ) ) | 
						
							| 17 | 16 6 | eqtrd | ⊢ ( 𝜑  →  ( 𝐼 ‘ 1 )  =  𝑌 ) | 
						
							| 18 | 9 | a1i | ⊢ ( 𝜑  →  ( Base ‘ 𝐺 )  =  ( Base ‘ 𝐺 ) ) | 
						
							| 19 | 1 3 4 18 | pi1eluni | ⊢ ( 𝜑  →  ( 𝐼  ∈  ∪  ( Base ‘ 𝐺 )  ↔  ( 𝐼  ∈  ( II  Cn  𝐽 )  ∧  ( 𝐼 ‘ 0 )  =  𝑌  ∧  ( 𝐼 ‘ 1 )  =  𝑌 ) ) ) | 
						
							| 20 | 13 15 17 19 | mpbir3and | ⊢ ( 𝜑  →  𝐼  ∈  ∪  ( Base ‘ 𝐺 ) ) | 
						
							| 21 | 1 3 4 18 | pi1eluni | ⊢ ( 𝜑  →  ( 𝐹  ∈  ∪  ( Base ‘ 𝐺 )  ↔  ( 𝐹  ∈  ( II  Cn  𝐽 )  ∧  ( 𝐹 ‘ 0 )  =  𝑌  ∧  ( 𝐹 ‘ 1 )  =  𝑌 ) ) ) | 
						
							| 22 | 5 6 7 21 | mpbir3and | ⊢ ( 𝜑  →  𝐹  ∈  ∪  ( Base ‘ 𝐺 ) ) | 
						
							| 23 | 1 9 3 4 10 20 22 | pi1addval | ⊢ ( 𝜑  →  ( [ 𝐼 ] (  ≃ph ‘ 𝐽 ) ( +g ‘ 𝐺 ) [ 𝐹 ] (  ≃ph ‘ 𝐽 ) )  =  [ ( 𝐼 ( *𝑝 ‘ 𝐽 ) 𝐹 ) ] (  ≃ph ‘ 𝐽 ) ) | 
						
							| 24 |  | phtpcer | ⊢ (  ≃ph ‘ 𝐽 )  Er  ( II  Cn  𝐽 ) | 
						
							| 25 | 24 | a1i | ⊢ ( 𝜑  →  (  ≃ph ‘ 𝐽 )  Er  ( II  Cn  𝐽 ) ) | 
						
							| 26 |  | eqid | ⊢ ( ( 0 [,] 1 )  ×  { ( 𝐹 ‘ 1 ) } )  =  ( ( 0 [,] 1 )  ×  { ( 𝐹 ‘ 1 ) } ) | 
						
							| 27 | 8 26 | pcorev | ⊢ ( 𝐹  ∈  ( II  Cn  𝐽 )  →  ( 𝐼 ( *𝑝 ‘ 𝐽 ) 𝐹 ) (  ≃ph ‘ 𝐽 ) ( ( 0 [,] 1 )  ×  { ( 𝐹 ‘ 1 ) } ) ) | 
						
							| 28 | 5 27 | syl | ⊢ ( 𝜑  →  ( 𝐼 ( *𝑝 ‘ 𝐽 ) 𝐹 ) (  ≃ph ‘ 𝐽 ) ( ( 0 [,] 1 )  ×  { ( 𝐹 ‘ 1 ) } ) ) | 
						
							| 29 | 7 | sneqd | ⊢ ( 𝜑  →  { ( 𝐹 ‘ 1 ) }  =  { 𝑌 } ) | 
						
							| 30 | 29 | xpeq2d | ⊢ ( 𝜑  →  ( ( 0 [,] 1 )  ×  { ( 𝐹 ‘ 1 ) } )  =  ( ( 0 [,] 1 )  ×  { 𝑌 } ) ) | 
						
							| 31 | 28 30 | breqtrd | ⊢ ( 𝜑  →  ( 𝐼 ( *𝑝 ‘ 𝐽 ) 𝐹 ) (  ≃ph ‘ 𝐽 ) ( ( 0 [,] 1 )  ×  { 𝑌 } ) ) | 
						
							| 32 | 25 31 | erthi | ⊢ ( 𝜑  →  [ ( 𝐼 ( *𝑝 ‘ 𝐽 ) 𝐹 ) ] (  ≃ph ‘ 𝐽 )  =  [ ( ( 0 [,] 1 )  ×  { 𝑌 } ) ] (  ≃ph ‘ 𝐽 ) ) | 
						
							| 33 |  | eqid | ⊢ ( ( 0 [,] 1 )  ×  { 𝑌 } )  =  ( ( 0 [,] 1 )  ×  { 𝑌 } ) | 
						
							| 34 | 1 9 3 4 33 | pi1grplem | ⊢ ( 𝜑  →  ( 𝐺  ∈  Grp  ∧  [ ( ( 0 [,] 1 )  ×  { 𝑌 } ) ] (  ≃ph ‘ 𝐽 )  =  ( 0g ‘ 𝐺 ) ) ) | 
						
							| 35 | 34 | simprd | ⊢ ( 𝜑  →  [ ( ( 0 [,] 1 )  ×  { 𝑌 } ) ] (  ≃ph ‘ 𝐽 )  =  ( 0g ‘ 𝐺 ) ) | 
						
							| 36 | 23 32 35 | 3eqtrd | ⊢ ( 𝜑  →  ( [ 𝐼 ] (  ≃ph ‘ 𝐽 ) ( +g ‘ 𝐺 ) [ 𝐹 ] (  ≃ph ‘ 𝐽 ) )  =  ( 0g ‘ 𝐺 ) ) | 
						
							| 37 | 34 | simpld | ⊢ ( 𝜑  →  𝐺  ∈  Grp ) | 
						
							| 38 | 1 9 3 4 5 6 7 | elpi1i | ⊢ ( 𝜑  →  [ 𝐹 ] (  ≃ph ‘ 𝐽 )  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 39 | 1 9 3 4 13 15 17 | elpi1i | ⊢ ( 𝜑  →  [ 𝐼 ] (  ≃ph ‘ 𝐽 )  ∈  ( Base ‘ 𝐺 ) ) | 
						
							| 40 |  | eqid | ⊢ ( 0g ‘ 𝐺 )  =  ( 0g ‘ 𝐺 ) | 
						
							| 41 | 9 10 40 2 | grpinvid2 | ⊢ ( ( 𝐺  ∈  Grp  ∧  [ 𝐹 ] (  ≃ph ‘ 𝐽 )  ∈  ( Base ‘ 𝐺 )  ∧  [ 𝐼 ] (  ≃ph ‘ 𝐽 )  ∈  ( Base ‘ 𝐺 ) )  →  ( ( 𝑁 ‘ [ 𝐹 ] (  ≃ph ‘ 𝐽 ) )  =  [ 𝐼 ] (  ≃ph ‘ 𝐽 )  ↔  ( [ 𝐼 ] (  ≃ph ‘ 𝐽 ) ( +g ‘ 𝐺 ) [ 𝐹 ] (  ≃ph ‘ 𝐽 ) )  =  ( 0g ‘ 𝐺 ) ) ) | 
						
							| 42 | 37 38 39 41 | syl3anc | ⊢ ( 𝜑  →  ( ( 𝑁 ‘ [ 𝐹 ] (  ≃ph ‘ 𝐽 ) )  =  [ 𝐼 ] (  ≃ph ‘ 𝐽 )  ↔  ( [ 𝐼 ] (  ≃ph ‘ 𝐽 ) ( +g ‘ 𝐺 ) [ 𝐹 ] (  ≃ph ‘ 𝐽 ) )  =  ( 0g ‘ 𝐺 ) ) ) | 
						
							| 43 | 36 42 | mpbird | ⊢ ( 𝜑  →  ( 𝑁 ‘ [ 𝐹 ] (  ≃ph ‘ 𝐽 ) )  =  [ 𝐼 ] (  ≃ph ‘ 𝐽 ) ) |