| Step | Hyp | Ref | Expression | 
						
							| 1 |  | hdmapg.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | hdmapg.u | ⊢ 𝑈  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 3 |  | hdmapg.v | ⊢ 𝑉  =  ( Base ‘ 𝑈 ) | 
						
							| 4 |  | hdmapg.s | ⊢ 𝑆  =  ( ( HDMap ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 5 |  | hdmapg.g | ⊢ 𝐺  =  ( ( HGMap ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 6 |  | hdmapg.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 7 |  | hdmapg.x | ⊢ ( 𝜑  →  𝑋  ∈  𝑉 ) | 
						
							| 8 |  | hdmapg.y | ⊢ ( 𝜑  →  𝑌  ∈  𝑉 ) | 
						
							| 9 |  | eqid | ⊢ 〈 (  I   ↾  ( Base ‘ 𝐾 ) ) ,  (  I   ↾  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) 〉  =  〈 (  I   ↾  ( Base ‘ 𝐾 ) ) ,  (  I   ↾  ( ( LTrn ‘ 𝐾 ) ‘ 𝑊 ) ) 〉 | 
						
							| 10 |  | eqid | ⊢ ( ( ocH ‘ 𝐾 ) ‘ 𝑊 )  =  ( ( ocH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 11 |  | eqid | ⊢ ( +g ‘ 𝑈 )  =  ( +g ‘ 𝑈 ) | 
						
							| 12 |  | eqid | ⊢ (  ·𝑠  ‘ 𝑈 )  =  (  ·𝑠  ‘ 𝑈 ) | 
						
							| 13 |  | eqid | ⊢ ( Scalar ‘ 𝑈 )  =  ( Scalar ‘ 𝑈 ) | 
						
							| 14 |  | eqid | ⊢ ( Base ‘ ( Scalar ‘ 𝑈 ) )  =  ( Base ‘ ( Scalar ‘ 𝑈 ) ) | 
						
							| 15 |  | eqid | ⊢ ( LSSum ‘ 𝑈 )  =  ( LSSum ‘ 𝑈 ) | 
						
							| 16 |  | eqid | ⊢ ( LSpan ‘ 𝑈 )  =  ( LSpan ‘ 𝑈 ) | 
						
							| 17 |  | eqid | ⊢ ( .r ‘ ( Scalar ‘ 𝑈 ) )  =  ( .r ‘ ( Scalar ‘ 𝑈 ) ) | 
						
							| 18 |  | eqid | ⊢ ( 0g ‘ ( Scalar ‘ 𝑈 ) )  =  ( 0g ‘ ( Scalar ‘ 𝑈 ) ) | 
						
							| 19 |  | eqid | ⊢ ( +g ‘ ( Scalar ‘ 𝑈 ) )  =  ( +g ‘ ( Scalar ‘ 𝑈 ) ) | 
						
							| 20 | 1 9 10 2 3 11 12 13 14 15 16 6 7 17 18 19 4 5 8 | hdmapglem7 | ⊢ ( 𝜑  →  ( 𝐺 ‘ ( ( 𝑆 ‘ 𝑌 ) ‘ 𝑋 ) )  =  ( ( 𝑆 ‘ 𝑋 ) ‘ 𝑌 ) ) |