| Step | Hyp | Ref | Expression | 
						
							| 1 |  | lclkrlem2m.v | ⊢ 𝑉  =  ( Base ‘ 𝑈 ) | 
						
							| 2 |  | lclkrlem2m.t | ⊢  ·   =  (  ·𝑠  ‘ 𝑈 ) | 
						
							| 3 |  | lclkrlem2m.s | ⊢ 𝑆  =  ( Scalar ‘ 𝑈 ) | 
						
							| 4 |  | lclkrlem2m.q | ⊢  ×   =  ( .r ‘ 𝑆 ) | 
						
							| 5 |  | lclkrlem2m.z | ⊢  0   =  ( 0g ‘ 𝑆 ) | 
						
							| 6 |  | lclkrlem2m.i | ⊢ 𝐼  =  ( invr ‘ 𝑆 ) | 
						
							| 7 |  | lclkrlem2m.m | ⊢  −   =  ( -g ‘ 𝑈 ) | 
						
							| 8 |  | lclkrlem2m.f | ⊢ 𝐹  =  ( LFnl ‘ 𝑈 ) | 
						
							| 9 |  | lclkrlem2m.d | ⊢ 𝐷  =  ( LDual ‘ 𝑈 ) | 
						
							| 10 |  | lclkrlem2m.p | ⊢  +   =  ( +g ‘ 𝐷 ) | 
						
							| 11 |  | lclkrlem2m.x | ⊢ ( 𝜑  →  𝑋  ∈  𝑉 ) | 
						
							| 12 |  | lclkrlem2m.y | ⊢ ( 𝜑  →  𝑌  ∈  𝑉 ) | 
						
							| 13 |  | lclkrlem2m.e | ⊢ ( 𝜑  →  𝐸  ∈  𝐹 ) | 
						
							| 14 |  | lclkrlem2m.g | ⊢ ( 𝜑  →  𝐺  ∈  𝐹 ) | 
						
							| 15 |  | lclkrlem2n.n | ⊢ 𝑁  =  ( LSpan ‘ 𝑈 ) | 
						
							| 16 |  | lclkrlem2n.l | ⊢ 𝐿  =  ( LKer ‘ 𝑈 ) | 
						
							| 17 |  | lclkrlem2o.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 18 |  | lclkrlem2o.o | ⊢  ⊥   =  ( ( ocH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 19 |  | lclkrlem2o.u | ⊢ 𝑈  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 20 |  | lclkrlem2o.a | ⊢  ⊕   =  ( LSSum ‘ 𝑈 ) | 
						
							| 21 |  | lclkrlem2o.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 22 |  | lclkrlem2q.le | ⊢ ( 𝜑  →  ( 𝐿 ‘ 𝐸 )  =  (  ⊥  ‘ { 𝑋 } ) ) | 
						
							| 23 |  | lclkrlem2q.lg | ⊢ ( 𝜑  →  ( 𝐿 ‘ 𝐺 )  =  (  ⊥  ‘ { 𝑌 } ) ) | 
						
							| 24 |  | lclkrlem2u.n | ⊢ ( 𝜑  →  ( ( 𝐸  +  𝐺 ) ‘ 𝑋 )  ≠   0  ) | 
						
							| 25 | 17 19 21 | dvhlmod | ⊢ ( 𝜑  →  𝑈  ∈  LMod ) | 
						
							| 26 | 8 9 10 25 13 14 | ldualvaddcom | ⊢ ( 𝜑  →  ( 𝐸  +  𝐺 )  =  ( 𝐺  +  𝐸 ) ) | 
						
							| 27 | 26 | fveq1d | ⊢ ( 𝜑  →  ( ( 𝐸  +  𝐺 ) ‘ 𝑋 )  =  ( ( 𝐺  +  𝐸 ) ‘ 𝑋 ) ) | 
						
							| 28 | 27 24 | eqnetrrd | ⊢ ( 𝜑  →  ( ( 𝐺  +  𝐸 ) ‘ 𝑋 )  ≠   0  ) | 
						
							| 29 | 1 2 3 4 5 6 7 8 9 10 12 11 14 13 15 16 17 18 19 20 21 23 22 28 | lclkrlem2t | ⊢ ( 𝜑  →  (  ⊥  ‘ (  ⊥  ‘ ( 𝐿 ‘ ( 𝐺  +  𝐸 ) ) ) )  =  ( 𝐿 ‘ ( 𝐺  +  𝐸 ) ) ) | 
						
							| 30 | 26 | fveq2d | ⊢ ( 𝜑  →  ( 𝐿 ‘ ( 𝐸  +  𝐺 ) )  =  ( 𝐿 ‘ ( 𝐺  +  𝐸 ) ) ) | 
						
							| 31 | 30 | fveq2d | ⊢ ( 𝜑  →  (  ⊥  ‘ ( 𝐿 ‘ ( 𝐸  +  𝐺 ) ) )  =  (  ⊥  ‘ ( 𝐿 ‘ ( 𝐺  +  𝐸 ) ) ) ) | 
						
							| 32 | 31 | fveq2d | ⊢ ( 𝜑  →  (  ⊥  ‘ (  ⊥  ‘ ( 𝐿 ‘ ( 𝐸  +  𝐺 ) ) ) )  =  (  ⊥  ‘ (  ⊥  ‘ ( 𝐿 ‘ ( 𝐺  +  𝐸 ) ) ) ) ) | 
						
							| 33 | 29 32 30 | 3eqtr4d | ⊢ ( 𝜑  →  (  ⊥  ‘ (  ⊥  ‘ ( 𝐿 ‘ ( 𝐸  +  𝐺 ) ) ) )  =  ( 𝐿 ‘ ( 𝐸  +  𝐺 ) ) ) |