| Step | Hyp | Ref | Expression | 
						
							| 1 |  | hgmapval.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | hgmapfval.u | ⊢ 𝑈  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 3 |  | hgmapfval.v | ⊢ 𝑉  =  ( Base ‘ 𝑈 ) | 
						
							| 4 |  | hgmapfval.t | ⊢  ·   =  (  ·𝑠  ‘ 𝑈 ) | 
						
							| 5 |  | hgmapfval.r | ⊢ 𝑅  =  ( Scalar ‘ 𝑈 ) | 
						
							| 6 |  | hgmapfval.b | ⊢ 𝐵  =  ( Base ‘ 𝑅 ) | 
						
							| 7 |  | hgmapfval.c | ⊢ 𝐶  =  ( ( LCDual ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 8 |  | hgmapfval.s | ⊢  ∙   =  (  ·𝑠  ‘ 𝐶 ) | 
						
							| 9 |  | hgmapfval.m | ⊢ 𝑀  =  ( ( HDMap ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 10 |  | hgmapfval.i | ⊢ 𝐼  =  ( ( HGMap ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 11 |  | hgmapfval.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  𝑌  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 12 |  | hgmapval.x | ⊢ ( 𝜑  →  𝑋  ∈  𝐵 ) | 
						
							| 13 | 1 2 3 4 5 6 7 8 9 10 11 | hgmapfval | ⊢ ( 𝜑  →  𝐼  =  ( 𝑥  ∈  𝐵  ↦  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) ) | 
						
							| 14 | 13 | fveq1d | ⊢ ( 𝜑  →  ( 𝐼 ‘ 𝑋 )  =  ( ( 𝑥  ∈  𝐵  ↦  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) ‘ 𝑋 ) ) | 
						
							| 15 |  | riotaex | ⊢ ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) )  ∈  V | 
						
							| 16 |  | fvoveq1 | ⊢ ( 𝑥  =  𝑋  →  ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) ) ) | 
						
							| 17 | 16 | eqeq1d | ⊢ ( 𝑥  =  𝑋  →  ( ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) )  ↔  ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) | 
						
							| 18 | 17 | ralbidv | ⊢ ( 𝑥  =  𝑋  →  ( ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) )  ↔  ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) | 
						
							| 19 | 18 | riotabidv | ⊢ ( 𝑥  =  𝑋  →  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) )  =  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) | 
						
							| 20 |  | eqid | ⊢ ( 𝑥  ∈  𝐵  ↦  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) )  =  ( 𝑥  ∈  𝐵  ↦  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) | 
						
							| 21 | 19 20 | fvmptg | ⊢ ( ( 𝑋  ∈  𝐵  ∧  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) )  ∈  V )  →  ( ( 𝑥  ∈  𝐵  ↦  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) ‘ 𝑋 )  =  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) | 
						
							| 22 | 12 15 21 | sylancl | ⊢ ( 𝜑  →  ( ( 𝑥  ∈  𝐵  ↦  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑥  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) ‘ 𝑋 )  =  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) | 
						
							| 23 | 14 22 | eqtrd | ⊢ ( 𝜑  →  ( 𝐼 ‘ 𝑋 )  =  ( ℩ 𝑦  ∈  𝐵 ∀ 𝑣  ∈  𝑉 ( 𝑀 ‘ ( 𝑋  ·  𝑣 ) )  =  ( 𝑦  ∙  ( 𝑀 ‘ 𝑣 ) ) ) ) |