| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dvadia.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | dvadia.u | ⊢ 𝑈  =  ( ( DVecA ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 3 |  | dvadia.i | ⊢ 𝐼  =  ( ( DIsoA ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 4 |  | dvadia.n | ⊢  ⊥   =  ( ( ocA ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 5 |  | dvadia.s | ⊢ 𝑆  =  ( LSubSp ‘ 𝑈 ) | 
						
							| 6 |  | simprr | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) | 
						
							| 7 |  | eqid | ⊢ ( Base ‘ 𝑈 )  =  ( Base ‘ 𝑈 ) | 
						
							| 8 | 7 5 | lssss | ⊢ ( 𝑋  ∈  𝑆  →  𝑋  ⊆  ( Base ‘ 𝑈 ) ) | 
						
							| 9 | 8 | ad2antrl | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  𝑋  ⊆  ( Base ‘ 𝑈 ) ) | 
						
							| 10 |  | eqid | ⊢ ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )  =  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 11 | 1 10 2 7 | dvavbase | ⊢ ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  →  ( Base ‘ 𝑈 )  =  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) | 
						
							| 12 | 11 | adantr | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  ( Base ‘ 𝑈 )  =  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) | 
						
							| 13 | 9 12 | sseqtrd | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  𝑋  ⊆  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) | 
						
							| 14 | 1 10 3 4 | docaclN | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  𝑋  ⊆  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) )  →  (  ⊥  ‘ 𝑋 )  ∈  ran  𝐼 ) | 
						
							| 15 | 13 14 | syldan | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  (  ⊥  ‘ 𝑋 )  ∈  ran  𝐼 ) | 
						
							| 16 | 1 10 3 | diaelrnN | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  (  ⊥  ‘ 𝑋 )  ∈  ran  𝐼 )  →  (  ⊥  ‘ 𝑋 )  ⊆  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) | 
						
							| 17 | 15 16 | syldan | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  (  ⊥  ‘ 𝑋 )  ⊆  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) | 
						
							| 18 | 1 10 3 4 | docaclN | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  (  ⊥  ‘ 𝑋 )  ⊆  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) )  →  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  ∈  ran  𝐼 ) | 
						
							| 19 | 17 18 | syldan | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  ∈  ran  𝐼 ) | 
						
							| 20 | 6 19 | eqeltrrd | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  ( 𝑋  ∈  𝑆  ∧  (  ⊥  ‘ (  ⊥  ‘ 𝑋 ) )  =  𝑋 ) )  →  𝑋  ∈  ran  𝐼 ) |