| Step | Hyp | Ref | Expression | 
						
							| 1 |  | hdmap11.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | hdmap11.u | ⊢ 𝑈  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 3 |  | hdmap11.v | ⊢ 𝑉  =  ( Base ‘ 𝑈 ) | 
						
							| 4 |  | hdmap11.p | ⊢  +   =  ( +g ‘ 𝑈 ) | 
						
							| 5 |  | hdmap11.c | ⊢ 𝐶  =  ( ( LCDual ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 6 |  | hdmap11.a | ⊢  ✚   =  ( +g ‘ 𝐶 ) | 
						
							| 7 |  | hdmap11.s | ⊢ 𝑆  =  ( ( HDMap ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 8 |  | hdmap11.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 9 |  | hdmap11.x | ⊢ ( 𝜑  →  𝑋  ∈  𝑉 ) | 
						
							| 10 |  | hdmap11.y | ⊢ ( 𝜑  →  𝑌  ∈  𝑉 ) | 
						
							| 11 |  | eqid | ⊢ 〈 (  I   ↾  ( Base ‘ 𝐾 ) ) ,  (  I   ↾  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) 〉  =  〈 (  I   ↾  ( Base ‘ 𝐾 ) ) ,  (  I   ↾  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) 〉 | 
						
							| 12 |  | eqid | ⊢ ( 0g ‘ 𝑈 )  =  ( 0g ‘ 𝑈 ) | 
						
							| 13 |  | eqid | ⊢ ( LSpan ‘ 𝑈 )  =  ( LSpan ‘ 𝑈 ) | 
						
							| 14 |  | eqid | ⊢ ( Base ‘ 𝐶 )  =  ( Base ‘ 𝐶 ) | 
						
							| 15 |  | eqid | ⊢ ( LSpan ‘ 𝐶 )  =  ( LSpan ‘ 𝐶 ) | 
						
							| 16 |  | eqid | ⊢ ( ( mapd ‘ 𝐾 ) ‘ 𝑊 )  =  ( ( mapd ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 17 |  | eqid | ⊢ ( ( HVMap ‘ 𝐾 ) ‘ 𝑊 )  =  ( ( HVMap ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 18 |  | eqid | ⊢ ( ( HDMap1 ‘ 𝐾 ) ‘ 𝑊 )  =  ( ( HDMap1 ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 19 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 | hdmap11lem2 | ⊢ ( 𝜑  →  ( 𝑆 ‘ ( 𝑋  +  𝑌 ) )  =  ( ( 𝑆 ‘ 𝑋 )  ✚  ( 𝑆 ‘ 𝑌 ) ) ) |