| Step | Hyp | Ref | Expression | 
						
							| 1 |  | hdmapglem7.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | hdmapglem7.e | ⊢ 𝐸  =  〈 (  I   ↾  ( Base ‘ 𝐾 ) ) ,  (  I   ↾  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) 〉 | 
						
							| 3 |  | hdmapglem7.o | ⊢ 𝑂  =  ( ( ocH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 4 |  | hdmapglem7.u | ⊢ 𝑈  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 5 |  | hdmapglem7.v | ⊢ 𝑉  =  ( Base ‘ 𝑈 ) | 
						
							| 6 |  | hdmapglem7.p | ⊢  +   =  ( +g ‘ 𝑈 ) | 
						
							| 7 |  | hdmapglem7.q | ⊢  ·   =  (  ·𝑠  ‘ 𝑈 ) | 
						
							| 8 |  | hdmapglem7.r | ⊢ 𝑅  =  ( Scalar ‘ 𝑈 ) | 
						
							| 9 |  | hdmapglem7.b | ⊢ 𝐵  =  ( Base ‘ 𝑅 ) | 
						
							| 10 |  | hdmapglem7.a | ⊢  ⊕   =  ( LSSum ‘ 𝑈 ) | 
						
							| 11 |  | hdmapglem7.n | ⊢ 𝑁  =  ( LSpan ‘ 𝑈 ) | 
						
							| 12 |  | hdmapglem7.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 13 |  | hdmapglem7.x | ⊢ ( 𝜑  →  𝑋  ∈  𝑉 ) | 
						
							| 14 |  | eqid | ⊢ ( LSubSp ‘ 𝑈 )  =  ( LSubSp ‘ 𝑈 ) | 
						
							| 15 | 1 4 12 | dvhlmod | ⊢ ( 𝜑  →  𝑈  ∈  LMod ) | 
						
							| 16 |  | eqid | ⊢ ( Base ‘ 𝐾 )  =  ( Base ‘ 𝐾 ) | 
						
							| 17 |  | eqid | ⊢ ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 )  =  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 18 |  | eqid | ⊢ ( 0g ‘ 𝑈 )  =  ( 0g ‘ 𝑈 ) | 
						
							| 19 | 1 16 17 4 5 18 2 12 | dvheveccl | ⊢ ( 𝜑  →  𝐸  ∈  ( 𝑉  ∖  { ( 0g ‘ 𝑈 ) } ) ) | 
						
							| 20 | 19 | eldifad | ⊢ ( 𝜑  →  𝐸  ∈  𝑉 ) | 
						
							| 21 | 5 14 11 | lspsncl | ⊢ ( ( 𝑈  ∈  LMod  ∧  𝐸  ∈  𝑉 )  →  ( 𝑁 ‘ { 𝐸 } )  ∈  ( LSubSp ‘ 𝑈 ) ) | 
						
							| 22 | 15 20 21 | syl2anc | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝐸 } )  ∈  ( LSubSp ‘ 𝑈 ) ) | 
						
							| 23 | 20 | snssd | ⊢ ( 𝜑  →  { 𝐸 }  ⊆  𝑉 ) | 
						
							| 24 | 1 4 3 5 11 12 23 | dochocsp | ⊢ ( 𝜑  →  ( 𝑂 ‘ ( 𝑁 ‘ { 𝐸 } ) )  =  ( 𝑂 ‘ { 𝐸 } ) ) | 
						
							| 25 | 24 | fveq2d | ⊢ ( 𝜑  →  ( 𝑂 ‘ ( 𝑂 ‘ ( 𝑁 ‘ { 𝐸 } ) ) )  =  ( 𝑂 ‘ ( 𝑂 ‘ { 𝐸 } ) ) ) | 
						
							| 26 | 1 4 3 5 11 12 20 | dochocsn | ⊢ ( 𝜑  →  ( 𝑂 ‘ ( 𝑂 ‘ { 𝐸 } ) )  =  ( 𝑁 ‘ { 𝐸 } ) ) | 
						
							| 27 | 25 26 | eqtrd | ⊢ ( 𝜑  →  ( 𝑂 ‘ ( 𝑂 ‘ ( 𝑁 ‘ { 𝐸 } ) ) )  =  ( 𝑁 ‘ { 𝐸 } ) ) | 
						
							| 28 | 1 3 4 5 14 10 12 22 27 | dochexmid | ⊢ ( 𝜑  →  ( ( 𝑁 ‘ { 𝐸 } )  ⊕  ( 𝑂 ‘ ( 𝑁 ‘ { 𝐸 } ) ) )  =  𝑉 ) | 
						
							| 29 | 24 | oveq2d | ⊢ ( 𝜑  →  ( ( 𝑁 ‘ { 𝐸 } )  ⊕  ( 𝑂 ‘ ( 𝑁 ‘ { 𝐸 } ) ) )  =  ( ( 𝑁 ‘ { 𝐸 } )  ⊕  ( 𝑂 ‘ { 𝐸 } ) ) ) | 
						
							| 30 | 28 29 | eqtr3d | ⊢ ( 𝜑  →  𝑉  =  ( ( 𝑁 ‘ { 𝐸 } )  ⊕  ( 𝑂 ‘ { 𝐸 } ) ) ) | 
						
							| 31 | 13 30 | eleqtrd | ⊢ ( 𝜑  →  𝑋  ∈  ( ( 𝑁 ‘ { 𝐸 } )  ⊕  ( 𝑂 ‘ { 𝐸 } ) ) ) | 
						
							| 32 | 14 | lsssssubg | ⊢ ( 𝑈  ∈  LMod  →  ( LSubSp ‘ 𝑈 )  ⊆  ( SubGrp ‘ 𝑈 ) ) | 
						
							| 33 | 15 32 | syl | ⊢ ( 𝜑  →  ( LSubSp ‘ 𝑈 )  ⊆  ( SubGrp ‘ 𝑈 ) ) | 
						
							| 34 | 33 22 | sseldd | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝐸 } )  ∈  ( SubGrp ‘ 𝑈 ) ) | 
						
							| 35 | 1 4 5 14 3 | dochlss | ⊢ ( ( ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 )  ∧  { 𝐸 }  ⊆  𝑉 )  →  ( 𝑂 ‘ { 𝐸 } )  ∈  ( LSubSp ‘ 𝑈 ) ) | 
						
							| 36 | 12 23 35 | syl2anc | ⊢ ( 𝜑  →  ( 𝑂 ‘ { 𝐸 } )  ∈  ( LSubSp ‘ 𝑈 ) ) | 
						
							| 37 | 33 36 | sseldd | ⊢ ( 𝜑  →  ( 𝑂 ‘ { 𝐸 } )  ∈  ( SubGrp ‘ 𝑈 ) ) | 
						
							| 38 | 6 10 | lsmelval | ⊢ ( ( ( 𝑁 ‘ { 𝐸 } )  ∈  ( SubGrp ‘ 𝑈 )  ∧  ( 𝑂 ‘ { 𝐸 } )  ∈  ( SubGrp ‘ 𝑈 ) )  →  ( 𝑋  ∈  ( ( 𝑁 ‘ { 𝐸 } )  ⊕  ( 𝑂 ‘ { 𝐸 } ) )  ↔  ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 ) ) ) | 
						
							| 39 | 34 37 38 | syl2anc | ⊢ ( 𝜑  →  ( 𝑋  ∈  ( ( 𝑁 ‘ { 𝐸 } )  ⊕  ( 𝑂 ‘ { 𝐸 } ) )  ↔  ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 ) ) ) | 
						
							| 40 | 31 39 | mpbid | ⊢ ( 𝜑  →  ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 ) ) | 
						
							| 41 |  | rexcom | ⊢ ( ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 )  ↔  ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 ) ) | 
						
							| 42 |  | df-rex | ⊢ ( ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 )  ↔  ∃ 𝑎 ( 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) ) ) | 
						
							| 43 | 8 9 5 7 11 | ellspsn | ⊢ ( ( 𝑈  ∈  LMod  ∧  𝐸  ∈  𝑉 )  →  ( 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } )  ↔  ∃ 𝑘  ∈  𝐵 𝑎  =  ( 𝑘  ·  𝐸 ) ) ) | 
						
							| 44 | 15 20 43 | syl2anc | ⊢ ( 𝜑  →  ( 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } )  ↔  ∃ 𝑘  ∈  𝐵 𝑎  =  ( 𝑘  ·  𝐸 ) ) ) | 
						
							| 45 | 44 | anbi1d | ⊢ ( 𝜑  →  ( ( 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ( ∃ 𝑘  ∈  𝐵 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) ) ) ) | 
						
							| 46 |  | r19.41v | ⊢ ( ∃ 𝑘  ∈  𝐵 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ( ∃ 𝑘  ∈  𝐵 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) ) ) | 
						
							| 47 | 45 46 | bitr4di | ⊢ ( 𝜑  →  ( ( 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ∃ 𝑘  ∈  𝐵 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) ) ) ) | 
						
							| 48 | 47 | exbidv | ⊢ ( 𝜑  →  ( ∃ 𝑎 ( 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ∃ 𝑎 ∃ 𝑘  ∈  𝐵 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) ) ) ) | 
						
							| 49 |  | rexcom4 | ⊢ ( ∃ 𝑘  ∈  𝐵 ∃ 𝑎 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ∃ 𝑎 ∃ 𝑘  ∈  𝐵 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) ) ) | 
						
							| 50 |  | ovex | ⊢ ( 𝑘  ·  𝐸 )  ∈  V | 
						
							| 51 |  | oveq1 | ⊢ ( 𝑎  =  ( 𝑘  ·  𝐸 )  →  ( 𝑎  +  𝑢 )  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) | 
						
							| 52 | 51 | eqeq2d | ⊢ ( 𝑎  =  ( 𝑘  ·  𝐸 )  →  ( 𝑋  =  ( 𝑎  +  𝑢 )  ↔  𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) ) | 
						
							| 53 | 50 52 | ceqsexv | ⊢ ( ∃ 𝑎 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) | 
						
							| 54 | 53 | rexbii | ⊢ ( ∃ 𝑘  ∈  𝐵 ∃ 𝑎 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ∃ 𝑘  ∈  𝐵 𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) | 
						
							| 55 | 49 54 | bitr3i | ⊢ ( ∃ 𝑎 ∃ 𝑘  ∈  𝐵 ( 𝑎  =  ( 𝑘  ·  𝐸 )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ∃ 𝑘  ∈  𝐵 𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) | 
						
							| 56 | 48 55 | bitrdi | ⊢ ( 𝜑  →  ( ∃ 𝑎 ( 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } )  ∧  𝑋  =  ( 𝑎  +  𝑢 ) )  ↔  ∃ 𝑘  ∈  𝐵 𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) ) | 
						
							| 57 | 42 56 | bitrid | ⊢ ( 𝜑  →  ( ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 )  ↔  ∃ 𝑘  ∈  𝐵 𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) ) | 
						
							| 58 | 57 | rexbidv | ⊢ ( 𝜑  →  ( ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 )  ↔  ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) ∃ 𝑘  ∈  𝐵 𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) ) | 
						
							| 59 | 41 58 | bitrid | ⊢ ( 𝜑  →  ( ∃ 𝑎  ∈  ( 𝑁 ‘ { 𝐸 } ) ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) 𝑋  =  ( 𝑎  +  𝑢 )  ↔  ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) ∃ 𝑘  ∈  𝐵 𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) ) | 
						
							| 60 | 40 59 | mpbid | ⊢ ( 𝜑  →  ∃ 𝑢  ∈  ( 𝑂 ‘ { 𝐸 } ) ∃ 𝑘  ∈  𝐵 𝑋  =  ( ( 𝑘  ·  𝐸 )  +  𝑢 ) ) |