| Step | Hyp | Ref | Expression | 
						
							| 1 |  | dvh4dimat.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | dvh4dimat.u | ⊢ 𝑈  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 3 |  | dvh2dimat.a | ⊢ 𝐴  =  ( LSAtoms ‘ 𝑈 ) | 
						
							| 4 |  | dvh2dimat.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 5 |  | dvh2dimat.p | ⊢ ( 𝜑  →  𝑃  ∈  𝐴 ) | 
						
							| 6 |  | eqid | ⊢ ( LSSum ‘ 𝑈 )  =  ( LSSum ‘ 𝑈 ) | 
						
							| 7 | 1 2 6 3 4 5 5 | dvh3dimatN | ⊢ ( 𝜑  →  ∃ 𝑠  ∈  𝐴 ¬  𝑠  ⊆  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 ) ) | 
						
							| 8 | 1 2 4 | dvhlmod | ⊢ ( 𝜑  →  𝑈  ∈  LMod ) | 
						
							| 9 |  | eqid | ⊢ ( LSubSp ‘ 𝑈 )  =  ( LSubSp ‘ 𝑈 ) | 
						
							| 10 | 9 3 8 5 | lsatlssel | ⊢ ( 𝜑  →  𝑃  ∈  ( LSubSp ‘ 𝑈 ) ) | 
						
							| 11 | 9 | lsssubg | ⊢ ( ( 𝑈  ∈  LMod  ∧  𝑃  ∈  ( LSubSp ‘ 𝑈 ) )  →  𝑃  ∈  ( SubGrp ‘ 𝑈 ) ) | 
						
							| 12 | 8 10 11 | syl2anc | ⊢ ( 𝜑  →  𝑃  ∈  ( SubGrp ‘ 𝑈 ) ) | 
						
							| 13 | 6 | lsmidm | ⊢ ( 𝑃  ∈  ( SubGrp ‘ 𝑈 )  →  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 )  =  𝑃 ) | 
						
							| 14 | 12 13 | syl | ⊢ ( 𝜑  →  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 )  =  𝑃 ) | 
						
							| 15 | 14 | sseq2d | ⊢ ( 𝜑  →  ( 𝑠  ⊆  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 )  ↔  𝑠  ⊆  𝑃 ) ) | 
						
							| 16 | 15 | adantr | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝐴 )  →  ( 𝑠  ⊆  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 )  ↔  𝑠  ⊆  𝑃 ) ) | 
						
							| 17 | 1 2 4 | dvhlvec | ⊢ ( 𝜑  →  𝑈  ∈  LVec ) | 
						
							| 18 | 17 | adantr | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝐴 )  →  𝑈  ∈  LVec ) | 
						
							| 19 |  | simpr | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝐴 )  →  𝑠  ∈  𝐴 ) | 
						
							| 20 | 5 | adantr | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝐴 )  →  𝑃  ∈  𝐴 ) | 
						
							| 21 | 3 18 19 20 | lsatcmp | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝐴 )  →  ( 𝑠  ⊆  𝑃  ↔  𝑠  =  𝑃 ) ) | 
						
							| 22 | 16 21 | bitrd | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝐴 )  →  ( 𝑠  ⊆  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 )  ↔  𝑠  =  𝑃 ) ) | 
						
							| 23 | 22 | necon3bbid | ⊢ ( ( 𝜑  ∧  𝑠  ∈  𝐴 )  →  ( ¬  𝑠  ⊆  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 )  ↔  𝑠  ≠  𝑃 ) ) | 
						
							| 24 | 23 | rexbidva | ⊢ ( 𝜑  →  ( ∃ 𝑠  ∈  𝐴 ¬  𝑠  ⊆  ( 𝑃 ( LSSum ‘ 𝑈 ) 𝑃 )  ↔  ∃ 𝑠  ∈  𝐴 𝑠  ≠  𝑃 ) ) | 
						
							| 25 | 7 24 | mpbid | ⊢ ( 𝜑  →  ∃ 𝑠  ∈  𝐴 𝑠  ≠  𝑃 ) |