| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mapdcnvord.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 2 |  | mapdcnvord.m | ⊢ 𝑀  =  ( ( mapd ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 3 |  | mapdcnvord.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 4 |  | mapdcnvord.x | ⊢ ( 𝜑  →  𝑋  ∈  ran  𝑀 ) | 
						
							| 5 |  | mapdcnvord.y | ⊢ ( 𝜑  →  𝑌  ∈  ran  𝑀 ) | 
						
							| 6 |  | eqid | ⊢ ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 )  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 7 |  | eqid | ⊢ ( LSubSp ‘ ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) )  =  ( LSubSp ‘ ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) ) | 
						
							| 8 | 1 2 6 7 3 4 | mapdcnvcl | ⊢ ( 𝜑  →  ( ◡ 𝑀 ‘ 𝑋 )  ∈  ( LSubSp ‘ ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) ) ) | 
						
							| 9 | 1 2 6 7 3 5 | mapdcnvcl | ⊢ ( 𝜑  →  ( ◡ 𝑀 ‘ 𝑌 )  ∈  ( LSubSp ‘ ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) ) ) | 
						
							| 10 | 1 6 7 2 3 8 9 | mapdord | ⊢ ( 𝜑  →  ( ( 𝑀 ‘ ( ◡ 𝑀 ‘ 𝑋 ) )  ⊆  ( 𝑀 ‘ ( ◡ 𝑀 ‘ 𝑌 ) )  ↔  ( ◡ 𝑀 ‘ 𝑋 )  ⊆  ( ◡ 𝑀 ‘ 𝑌 ) ) ) | 
						
							| 11 | 1 2 3 4 | mapdcnvid2 | ⊢ ( 𝜑  →  ( 𝑀 ‘ ( ◡ 𝑀 ‘ 𝑋 ) )  =  𝑋 ) | 
						
							| 12 | 1 2 3 5 | mapdcnvid2 | ⊢ ( 𝜑  →  ( 𝑀 ‘ ( ◡ 𝑀 ‘ 𝑌 ) )  =  𝑌 ) | 
						
							| 13 | 11 12 | sseq12d | ⊢ ( 𝜑  →  ( ( 𝑀 ‘ ( ◡ 𝑀 ‘ 𝑋 ) )  ⊆  ( 𝑀 ‘ ( ◡ 𝑀 ‘ 𝑌 ) )  ↔  𝑋  ⊆  𝑌 ) ) | 
						
							| 14 | 10 13 | bitr3d | ⊢ ( 𝜑  →  ( ( ◡ 𝑀 ‘ 𝑋 )  ⊆  ( ◡ 𝑀 ‘ 𝑌 )  ↔  𝑋  ⊆  𝑌 ) ) |