| Step | Hyp | Ref | Expression | 
						
							| 1 |  | sconnpconn | ⊢ ( 𝑅  ∈  SConn  →  𝑅  ∈  PConn ) | 
						
							| 2 |  | sconnpconn | ⊢ ( 𝑆  ∈  SConn  →  𝑆  ∈  PConn ) | 
						
							| 3 |  | txpconn | ⊢ ( ( 𝑅  ∈  PConn  ∧  𝑆  ∈  PConn )  →  ( 𝑅  ×t  𝑆 )  ∈  PConn ) | 
						
							| 4 | 1 2 3 | syl2an | ⊢ ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  →  ( 𝑅  ×t  𝑆 )  ∈  PConn ) | 
						
							| 5 |  | simpll | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑅  ∈  SConn ) | 
						
							| 6 |  | simprl | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) ) ) | 
						
							| 7 |  | sconntop | ⊢ ( 𝑅  ∈  SConn  →  𝑅  ∈  Top ) | 
						
							| 8 | 7 | ad2antrr | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑅  ∈  Top ) | 
						
							| 9 |  | eqid | ⊢ ∪  𝑅  =  ∪  𝑅 | 
						
							| 10 | 9 | toptopon | ⊢ ( 𝑅  ∈  Top  ↔  𝑅  ∈  ( TopOn ‘ ∪  𝑅 ) ) | 
						
							| 11 | 8 10 | sylib | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑅  ∈  ( TopOn ‘ ∪  𝑅 ) ) | 
						
							| 12 |  | sconntop | ⊢ ( 𝑆  ∈  SConn  →  𝑆  ∈  Top ) | 
						
							| 13 | 12 | ad2antlr | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑆  ∈  Top ) | 
						
							| 14 |  | eqid | ⊢ ∪  𝑆  =  ∪  𝑆 | 
						
							| 15 | 14 | toptopon | ⊢ ( 𝑆  ∈  Top  ↔  𝑆  ∈  ( TopOn ‘ ∪  𝑆 ) ) | 
						
							| 16 | 13 15 | sylib | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑆  ∈  ( TopOn ‘ ∪  𝑆 ) ) | 
						
							| 17 |  | tx1cn | ⊢ ( ( 𝑅  ∈  ( TopOn ‘ ∪  𝑅 )  ∧  𝑆  ∈  ( TopOn ‘ ∪  𝑆 ) )  →  ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∈  ( ( 𝑅  ×t  𝑆 )  Cn  𝑅 ) ) | 
						
							| 18 | 11 16 17 | syl2anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∈  ( ( 𝑅  ×t  𝑆 )  Cn  𝑅 ) ) | 
						
							| 19 |  | cnco | ⊢ ( ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∈  ( ( 𝑅  ×t  𝑆 )  Cn  𝑅 ) )  →  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑅 ) ) | 
						
							| 20 | 6 18 19 | syl2anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑅 ) ) | 
						
							| 21 |  | simprr | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) | 
						
							| 22 | 21 | fveq2d | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 0 ) )  =  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 1 ) ) ) | 
						
							| 23 |  | iitopon | ⊢ II  ∈  ( TopOn ‘ ( 0 [,] 1 ) ) | 
						
							| 24 | 23 | a1i | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  II  ∈  ( TopOn ‘ ( 0 [,] 1 ) ) ) | 
						
							| 25 |  | txtopon | ⊢ ( ( 𝑅  ∈  ( TopOn ‘ ∪  𝑅 )  ∧  𝑆  ∈  ( TopOn ‘ ∪  𝑆 ) )  →  ( 𝑅  ×t  𝑆 )  ∈  ( TopOn ‘ ( ∪  𝑅  ×  ∪  𝑆 ) ) ) | 
						
							| 26 | 11 16 25 | syl2anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( 𝑅  ×t  𝑆 )  ∈  ( TopOn ‘ ( ∪  𝑅  ×  ∪  𝑆 ) ) ) | 
						
							| 27 |  | cnf2 | ⊢ ( ( II  ∈  ( TopOn ‘ ( 0 [,] 1 ) )  ∧  ( 𝑅  ×t  𝑆 )  ∈  ( TopOn ‘ ( ∪  𝑅  ×  ∪  𝑆 ) )  ∧  𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) ) )  →  𝑓 : ( 0 [,] 1 ) ⟶ ( ∪  𝑅  ×  ∪  𝑆 ) ) | 
						
							| 28 | 24 26 6 27 | syl3anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑓 : ( 0 [,] 1 ) ⟶ ( ∪  𝑅  ×  ∪  𝑆 ) ) | 
						
							| 29 |  | 0elunit | ⊢ 0  ∈  ( 0 [,] 1 ) | 
						
							| 30 |  | fvco3 | ⊢ ( ( 𝑓 : ( 0 [,] 1 ) ⟶ ( ∪  𝑅  ×  ∪  𝑆 )  ∧  0  ∈  ( 0 [,] 1 ) )  →  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 0 ) ) ) | 
						
							| 31 | 28 29 30 | sylancl | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 0 ) ) ) | 
						
							| 32 |  | 1elunit | ⊢ 1  ∈  ( 0 [,] 1 ) | 
						
							| 33 |  | fvco3 | ⊢ ( ( 𝑓 : ( 0 [,] 1 ) ⟶ ( ∪  𝑅  ×  ∪  𝑆 )  ∧  1  ∈  ( 0 [,] 1 ) )  →  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 )  =  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 1 ) ) ) | 
						
							| 34 | 28 32 33 | sylancl | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 )  =  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 1 ) ) ) | 
						
							| 35 | 22 31 34 | 3eqtr4d | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 ) ) | 
						
							| 36 |  | sconnpht | ⊢ ( ( 𝑅  ∈  SConn  ∧  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑅 )  ∧  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 ) )  →  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) (  ≃ph ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) | 
						
							| 37 | 5 20 35 36 | syl3anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) (  ≃ph ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) | 
						
							| 38 |  | isphtpc | ⊢ ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) (  ≃ph ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } )  ↔  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑅 )  ∧  ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } )  ∈  ( II  Cn  𝑅 )  ∧  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅ ) ) | 
						
							| 39 | 37 38 | sylib | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑅 )  ∧  ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } )  ∈  ( II  Cn  𝑅 )  ∧  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅ ) ) | 
						
							| 40 | 39 | simp3d | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅ ) | 
						
							| 41 |  | n0 | ⊢ ( ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅  ↔  ∃ 𝑔 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) | 
						
							| 42 | 40 41 | sylib | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ∃ 𝑔 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) | 
						
							| 43 |  | simplr | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑆  ∈  SConn ) | 
						
							| 44 |  | tx2cn | ⊢ ( ( 𝑅  ∈  ( TopOn ‘ ∪  𝑅 )  ∧  𝑆  ∈  ( TopOn ‘ ∪  𝑆 ) )  →  ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∈  ( ( 𝑅  ×t  𝑆 )  Cn  𝑆 ) ) | 
						
							| 45 | 11 16 44 | syl2anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∈  ( ( 𝑅  ×t  𝑆 )  Cn  𝑆 ) ) | 
						
							| 46 |  | cnco | ⊢ ( ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∈  ( ( 𝑅  ×t  𝑆 )  Cn  𝑆 ) )  →  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑆 ) ) | 
						
							| 47 | 6 45 46 | syl2anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑆 ) ) | 
						
							| 48 | 21 | fveq2d | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 0 ) )  =  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 1 ) ) ) | 
						
							| 49 |  | fvco3 | ⊢ ( ( 𝑓 : ( 0 [,] 1 ) ⟶ ( ∪  𝑅  ×  ∪  𝑆 )  ∧  0  ∈  ( 0 [,] 1 ) )  →  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 0 ) ) ) | 
						
							| 50 | 28 29 49 | sylancl | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 0 ) ) ) | 
						
							| 51 |  | fvco3 | ⊢ ( ( 𝑓 : ( 0 [,] 1 ) ⟶ ( ∪  𝑅  ×  ∪  𝑆 )  ∧  1  ∈  ( 0 [,] 1 ) )  →  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 )  =  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 1 ) ) ) | 
						
							| 52 | 28 32 51 | sylancl | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 )  =  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) ) ‘ ( 𝑓 ‘ 1 ) ) ) | 
						
							| 53 | 48 50 52 | 3eqtr4d | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 ) ) | 
						
							| 54 |  | sconnpht | ⊢ ( ( 𝑆  ∈  SConn  ∧  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑆 )  ∧  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 )  =  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 1 ) )  →  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) (  ≃ph ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) | 
						
							| 55 | 43 47 53 54 | syl3anc | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) (  ≃ph ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) | 
						
							| 56 |  | isphtpc | ⊢ ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) (  ≃ph ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } )  ↔  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑆 )  ∧  ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } )  ∈  ( II  Cn  𝑆 )  ∧  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅ ) ) | 
						
							| 57 | 55 56 | sylib | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  ∈  ( II  Cn  𝑆 )  ∧  ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } )  ∈  ( II  Cn  𝑆 )  ∧  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅ ) ) | 
						
							| 58 | 57 | simp3d | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅ ) | 
						
							| 59 |  | n0 | ⊢ ( ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ≠  ∅  ↔  ∃ ℎ ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) | 
						
							| 60 | 58 59 | sylib | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ∃ ℎ ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) | 
						
							| 61 |  | exdistrv | ⊢ ( ∃ 𝑔 ∃ ℎ ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) )  ↔  ( ∃ 𝑔 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ∃ ℎ ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) ) | 
						
							| 62 | 8 | adantr | ⊢ ( ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  ∧  ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) )  →  𝑅  ∈  Top ) | 
						
							| 63 | 13 | adantr | ⊢ ( ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  ∧  ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) )  →  𝑆  ∈  Top ) | 
						
							| 64 | 6 | adantr | ⊢ ( ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  ∧  ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) )  →  𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) ) ) | 
						
							| 65 |  | eqid | ⊢ ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  =  ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) | 
						
							| 66 |  | eqid | ⊢ ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 )  =  ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) | 
						
							| 67 |  | simprl | ⊢ ( ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  ∧  ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) )  →  𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) | 
						
							| 68 |  | simprr | ⊢ ( ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  ∧  ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) )  →  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) | 
						
							| 69 | 62 63 64 65 66 67 68 | txsconnlem | ⊢ ( ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  ∧  ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) ) )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) | 
						
							| 70 | 69 | ex | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) ) | 
						
							| 71 | 70 | exlimdvv | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ∃ 𝑔 ∃ ℎ ( 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) ) | 
						
							| 72 | 61 71 | biimtrrid | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  ( ( ∃ 𝑔 𝑔  ∈  ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑅 ) ( ( 0 [,] 1 )  ×  { ( ( ( 1st   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) )  ∧  ∃ ℎ ℎ  ∈  ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ( PHtpy ‘ 𝑆 ) ( ( 0 [,] 1 )  ×  { ( ( ( 2nd   ↾  ( ∪  𝑅  ×  ∪  𝑆 ) )  ∘  𝑓 ) ‘ 0 ) } ) ) )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) ) | 
						
							| 73 | 42 60 72 | mp2and | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  ( 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) )  ∧  ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 ) ) )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) | 
						
							| 74 | 73 | expr | ⊢ ( ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  ∧  𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) ) )  →  ( ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) ) | 
						
							| 75 | 74 | ralrimiva | ⊢ ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  →  ∀ 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) ) ( ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) ) | 
						
							| 76 |  | issconn | ⊢ ( ( 𝑅  ×t  𝑆 )  ∈  SConn  ↔  ( ( 𝑅  ×t  𝑆 )  ∈  PConn  ∧  ∀ 𝑓  ∈  ( II  Cn  ( 𝑅  ×t  𝑆 ) ) ( ( 𝑓 ‘ 0 )  =  ( 𝑓 ‘ 1 )  →  𝑓 (  ≃ph ‘ ( 𝑅  ×t  𝑆 ) ) ( ( 0 [,] 1 )  ×  { ( 𝑓 ‘ 0 ) } ) ) ) ) | 
						
							| 77 | 4 75 76 | sylanbrc | ⊢ ( ( 𝑅  ∈  SConn  ∧  𝑆  ∈  SConn )  →  ( 𝑅  ×t  𝑆 )  ∈  SConn ) |