| Step | Hyp | Ref | Expression | 
						
							| 1 |  | ldilcnv.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | ldilcnv.d | ⊢ 𝐷  =  ( ( LDil ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 3 |  | simpll | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  𝐾  ∈  HL ) | 
						
							| 4 |  | eqid | ⊢ ( LAut ‘ 𝐾 )  =  ( LAut ‘ 𝐾 ) | 
						
							| 5 | 1 4 2 | ldillaut | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  𝐹  ∈  ( LAut ‘ 𝐾 ) ) | 
						
							| 6 | 4 | lautcnv | ⊢ ( ( 𝐾  ∈  HL  ∧  𝐹  ∈  ( LAut ‘ 𝐾 ) )  →  ◡ 𝐹  ∈  ( LAut ‘ 𝐾 ) ) | 
						
							| 7 | 3 5 6 | syl2anc | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  ◡ 𝐹  ∈  ( LAut ‘ 𝐾 ) ) | 
						
							| 8 |  | eqid | ⊢ ( Base ‘ 𝐾 )  =  ( Base ‘ 𝐾 ) | 
						
							| 9 |  | eqid | ⊢ ( le ‘ 𝐾 )  =  ( le ‘ 𝐾 ) | 
						
							| 10 | 8 9 1 2 | ldilval | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷  ∧  ( 𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 ) )  →  ( 𝐹 ‘ 𝑥 )  =  𝑥 ) | 
						
							| 11 | 10 | 3expa | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  ∧  ( 𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 ) )  →  ( 𝐹 ‘ 𝑥 )  =  𝑥 ) | 
						
							| 12 | 11 | 3impb | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  ∧  𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 )  →  ( 𝐹 ‘ 𝑥 )  =  𝑥 ) | 
						
							| 13 | 12 | fveq2d | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  ∧  𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 )  →  ( ◡ 𝐹 ‘ ( 𝐹 ‘ 𝑥 ) )  =  ( ◡ 𝐹 ‘ 𝑥 ) ) | 
						
							| 14 | 8 1 2 | ldil1o | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  𝐹 : ( Base ‘ 𝐾 ) –1-1-onto→ ( Base ‘ 𝐾 ) ) | 
						
							| 15 | 14 | 3ad2ant1 | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  ∧  𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 )  →  𝐹 : ( Base ‘ 𝐾 ) –1-1-onto→ ( Base ‘ 𝐾 ) ) | 
						
							| 16 |  | simp2 | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  ∧  𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 )  →  𝑥  ∈  ( Base ‘ 𝐾 ) ) | 
						
							| 17 |  | f1ocnvfv1 | ⊢ ( ( 𝐹 : ( Base ‘ 𝐾 ) –1-1-onto→ ( Base ‘ 𝐾 )  ∧  𝑥  ∈  ( Base ‘ 𝐾 ) )  →  ( ◡ 𝐹 ‘ ( 𝐹 ‘ 𝑥 ) )  =  𝑥 ) | 
						
							| 18 | 15 16 17 | syl2anc | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  ∧  𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 )  →  ( ◡ 𝐹 ‘ ( 𝐹 ‘ 𝑥 ) )  =  𝑥 ) | 
						
							| 19 | 13 18 | eqtr3d | ⊢ ( ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  ∧  𝑥  ∈  ( Base ‘ 𝐾 )  ∧  𝑥 ( le ‘ 𝐾 ) 𝑊 )  →  ( ◡ 𝐹 ‘ 𝑥 )  =  𝑥 ) | 
						
							| 20 | 19 | 3exp | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  ( 𝑥  ∈  ( Base ‘ 𝐾 )  →  ( 𝑥 ( le ‘ 𝐾 ) 𝑊  →  ( ◡ 𝐹 ‘ 𝑥 )  =  𝑥 ) ) ) | 
						
							| 21 | 20 | ralrimiv | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  ∀ 𝑥  ∈  ( Base ‘ 𝐾 ) ( 𝑥 ( le ‘ 𝐾 ) 𝑊  →  ( ◡ 𝐹 ‘ 𝑥 )  =  𝑥 ) ) | 
						
							| 22 | 8 9 1 4 2 | isldil | ⊢ ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  →  ( ◡ 𝐹  ∈  𝐷  ↔  ( ◡ 𝐹  ∈  ( LAut ‘ 𝐾 )  ∧  ∀ 𝑥  ∈  ( Base ‘ 𝐾 ) ( 𝑥 ( le ‘ 𝐾 ) 𝑊  →  ( ◡ 𝐹 ‘ 𝑥 )  =  𝑥 ) ) ) ) | 
						
							| 23 | 22 | adantr | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  ( ◡ 𝐹  ∈  𝐷  ↔  ( ◡ 𝐹  ∈  ( LAut ‘ 𝐾 )  ∧  ∀ 𝑥  ∈  ( Base ‘ 𝐾 ) ( 𝑥 ( le ‘ 𝐾 ) 𝑊  →  ( ◡ 𝐹 ‘ 𝑥 )  =  𝑥 ) ) ) ) | 
						
							| 24 | 7 21 23 | mpbir2and | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝐹  ∈  𝐷 )  →  ◡ 𝐹  ∈  𝐷 ) |