| Step | Hyp | Ref | Expression | 
						
							| 1 |  | prjsprel.1 | ⊢  ∼   =  { 〈 𝑥 ,  𝑦 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) } | 
						
							| 2 |  | prjspertr.b | ⊢ 𝐵  =  ( ( Base ‘ 𝑉 )  ∖  { ( 0g ‘ 𝑉 ) } ) | 
						
							| 3 |  | prjspertr.s | ⊢ 𝑆  =  ( Scalar ‘ 𝑉 ) | 
						
							| 4 |  | prjspertr.x | ⊢  ·   =  (  ·𝑠  ‘ 𝑉 ) | 
						
							| 5 |  | prjspertr.k | ⊢ 𝐾  =  ( Base ‘ 𝑆 ) | 
						
							| 6 |  | prjsprellsp.n | ⊢ 𝑁  =  ( LSpan ‘ 𝑉 ) | 
						
							| 7 | 1 | cnveqi | ⊢ ◡  ∼   =  ◡ { 〈 𝑥 ,  𝑦 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) } | 
						
							| 8 |  | cnvopab | ⊢ ◡ { 〈 𝑥 ,  𝑦 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  =  { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) } | 
						
							| 9 | 7 8 | eqtri | ⊢ ◡  ∼   =  { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) } | 
						
							| 10 | 9 | eceq2i | ⊢ [ 𝑋 ] ◡  ∼   =  [ 𝑋 ] { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) } | 
						
							| 11 |  | df-ec | ⊢ [ 𝑋 ] { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  =  ( { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  “  { 𝑋 } ) | 
						
							| 12 | 11 | a1i | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  [ 𝑋 ] { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  =  ( { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  “  { 𝑋 } ) ) | 
						
							| 13 |  | imaopab | ⊢ ( { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  “  { 𝑋 } )  =  { 𝑥  ∣  ∃ 𝑦  ∈  { 𝑋 } ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) } | 
						
							| 14 | 13 | a1i | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  ( { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  “  { 𝑋 } )  =  { 𝑥  ∣  ∃ 𝑦  ∈  { 𝑋 } ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) } ) | 
						
							| 15 |  | df-rex | ⊢ ( ∃ 𝑦  ∈  { 𝑋 } ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) )  ↔  ∃ 𝑦 ( 𝑦  ∈  { 𝑋 }  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) ) ) | 
						
							| 16 |  | velsn | ⊢ ( 𝑦  ∈  { 𝑋 }  ↔  𝑦  =  𝑋 ) | 
						
							| 17 | 16 | anbi1i | ⊢ ( ( 𝑦  ∈  { 𝑋 }  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) )  ↔  ( 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) ) ) | 
						
							| 18 |  | eleq1 | ⊢ ( 𝑦  =  𝑋  →  ( 𝑦  ∈  𝐵  ↔  𝑋  ∈  𝐵 ) ) | 
						
							| 19 | 18 | anbi2d | ⊢ ( 𝑦  =  𝑋  →  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ↔  ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 ) ) ) | 
						
							| 20 |  | oveq2 | ⊢ ( 𝑦  =  𝑋  →  ( 𝑙  ·  𝑦 )  =  ( 𝑙  ·  𝑋 ) ) | 
						
							| 21 | 20 | eqeq2d | ⊢ ( 𝑦  =  𝑋  →  ( 𝑥  =  ( 𝑙  ·  𝑦 )  ↔  𝑥  =  ( 𝑙  ·  𝑋 ) ) ) | 
						
							| 22 | 21 | rexbidv | ⊢ ( 𝑦  =  𝑋  →  ( ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 )  ↔  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) | 
						
							| 23 | 19 22 | anbi12d | ⊢ ( 𝑦  =  𝑋  →  ( ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) )  ↔  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 24 | 23 | pm5.32i | ⊢ ( ( 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) )  ↔  ( 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 25 | 17 24 | bitri | ⊢ ( ( 𝑦  ∈  { 𝑋 }  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) )  ↔  ( 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 26 | 25 | exbii | ⊢ ( ∃ 𝑦 ( 𝑦  ∈  { 𝑋 }  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) )  ↔  ∃ 𝑦 ( 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 27 |  | 19.41v | ⊢ ( ∃ 𝑦 ( 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) )  ↔  ( ∃ 𝑦 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 28 |  | elisset | ⊢ ( 𝑋  ∈  𝐵  →  ∃ 𝑦 𝑦  =  𝑋 ) | 
						
							| 29 | 28 | ad2antlr | ⊢ ( ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) )  →  ∃ 𝑦 𝑦  =  𝑋 ) | 
						
							| 30 | 29 | pm4.71ri | ⊢ ( ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) )  ↔  ( ∃ 𝑦 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 31 | 27 30 | bitr4i | ⊢ ( ∃ 𝑦 ( 𝑦  =  𝑋  ∧  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) )  ↔  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) | 
						
							| 32 | 15 26 31 | 3bitri | ⊢ ( ∃ 𝑦  ∈  { 𝑋 } ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) )  ↔  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) | 
						
							| 33 | 32 | abbii | ⊢ { 𝑥  ∣  ∃ 𝑦  ∈  { 𝑋 } ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  =  { 𝑥  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } | 
						
							| 34 |  | iba | ⊢ ( 𝑋  ∈  𝐵  →  ( 𝑥  ∈  𝐵  ↔  ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 ) ) ) | 
						
							| 35 | 34 | bicomd | ⊢ ( 𝑋  ∈  𝐵  →  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ↔  𝑥  ∈  𝐵 ) ) | 
						
							| 36 | 35 | anbi1d | ⊢ ( 𝑋  ∈  𝐵  →  ( ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) )  ↔  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 37 | 36 | abbidv | ⊢ ( 𝑋  ∈  𝐵  →  { 𝑥  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑋  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) }  =  { 𝑥  ∣  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } ) | 
						
							| 38 | 33 37 | eqtrid | ⊢ ( 𝑋  ∈  𝐵  →  { 𝑥  ∣  ∃ 𝑦  ∈  { 𝑋 } ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  =  { 𝑥  ∣  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } ) | 
						
							| 39 | 38 | adantl | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  { 𝑥  ∣  ∃ 𝑦  ∈  { 𝑋 } ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  =  { 𝑥  ∣  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } ) | 
						
							| 40 | 12 14 39 | 3eqtrd | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  [ 𝑋 ] { 〈 𝑦 ,  𝑥 〉  ∣  ( ( 𝑥  ∈  𝐵  ∧  𝑦  ∈  𝐵 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑦 ) ) }  =  { 𝑥  ∣  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } ) | 
						
							| 41 | 10 40 | eqtrid | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  [ 𝑋 ] ◡  ∼   =  { 𝑥  ∣  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } ) | 
						
							| 42 |  | df-rab | ⊢ { 𝑥  ∈  𝐵  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  =  { 𝑥  ∣  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } | 
						
							| 43 | 42 | a1i | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  { 𝑥  ∈  𝐵  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  =  { 𝑥  ∣  ( 𝑥  ∈  𝐵  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } ) | 
						
							| 44 | 2 | rabeqi | ⊢ { 𝑥  ∈  𝐵  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  =  { 𝑥  ∈  ( ( Base ‘ 𝑉 )  ∖  { ( 0g ‘ 𝑉 ) } )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) } | 
						
							| 45 |  | rabdif | ⊢ ( { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  ∖  { ( 0g ‘ 𝑉 ) } )  =  { 𝑥  ∈  ( ( Base ‘ 𝑉 )  ∖  { ( 0g ‘ 𝑉 ) } )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) } | 
						
							| 46 | 45 | a1i | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  ( { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  ∖  { ( 0g ‘ 𝑉 ) } )  =  { 𝑥  ∈  ( ( Base ‘ 𝑉 )  ∖  { ( 0g ‘ 𝑉 ) } )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) } ) | 
						
							| 47 | 44 46 | eqtr4id | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  { 𝑥  ∈  𝐵  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  =  ( { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  ∖  { ( 0g ‘ 𝑉 ) } ) ) | 
						
							| 48 | 41 43 47 | 3eqtr2d | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  [ 𝑋 ] ◡  ∼   =  ( { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  ∖  { ( 0g ‘ 𝑉 ) } ) ) | 
						
							| 49 | 1 2 3 4 5 | prjsper | ⊢ ( 𝑉  ∈  LVec  →   ∼   Er  𝐵 ) | 
						
							| 50 | 49 | adantr | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →   ∼   Er  𝐵 ) | 
						
							| 51 |  | ercnv | ⊢ (  ∼   Er  𝐵  →  ◡  ∼   =   ∼  ) | 
						
							| 52 | 51 | eqcomd | ⊢ (  ∼   Er  𝐵  →   ∼   =  ◡  ∼  ) | 
						
							| 53 | 50 52 | syl | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →   ∼   =  ◡  ∼  ) | 
						
							| 54 | 53 | eceq2d | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  [ 𝑋 ]  ∼   =  [ 𝑋 ] ◡  ∼  ) | 
						
							| 55 |  | lveclmod | ⊢ ( 𝑉  ∈  LVec  →  𝑉  ∈  LMod ) | 
						
							| 56 |  | difss | ⊢ ( ( Base ‘ 𝑉 )  ∖  { ( 0g ‘ 𝑉 ) } )  ⊆  ( Base ‘ 𝑉 ) | 
						
							| 57 | 2 56 | eqsstri | ⊢ 𝐵  ⊆  ( Base ‘ 𝑉 ) | 
						
							| 58 | 57 | sseli | ⊢ ( 𝑋  ∈  𝐵  →  𝑋  ∈  ( Base ‘ 𝑉 ) ) | 
						
							| 59 |  | eqid | ⊢ ( Base ‘ 𝑉 )  =  ( Base ‘ 𝑉 ) | 
						
							| 60 | 3 5 59 4 6 | lspsn | ⊢ ( ( 𝑉  ∈  LMod  ∧  𝑋  ∈  ( Base ‘ 𝑉 ) )  →  ( 𝑁 ‘ { 𝑋 } )  =  { 𝑥  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) } ) | 
						
							| 61 | 55 58 60 | syl2an | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  ( 𝑁 ‘ { 𝑋 } )  =  { 𝑥  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) } ) | 
						
							| 62 |  | simpr | ⊢ ( ( ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  ∧  𝑙  ∈  𝐾 )  ∧  𝑥  =  ( 𝑙  ·  𝑋 ) )  →  𝑥  =  ( 𝑙  ·  𝑋 ) ) | 
						
							| 63 | 55 | adantr | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  𝑉  ∈  LMod ) | 
						
							| 64 | 63 | adantr | ⊢ ( ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  ∧  𝑙  ∈  𝐾 )  →  𝑉  ∈  LMod ) | 
						
							| 65 |  | simpr | ⊢ ( ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  ∧  𝑙  ∈  𝐾 )  →  𝑙  ∈  𝐾 ) | 
						
							| 66 | 58 | ad2antlr | ⊢ ( ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  ∧  𝑙  ∈  𝐾 )  →  𝑋  ∈  ( Base ‘ 𝑉 ) ) | 
						
							| 67 | 59 3 4 5 64 65 66 | lmodvscld | ⊢ ( ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  ∧  𝑙  ∈  𝐾 )  →  ( 𝑙  ·  𝑋 )  ∈  ( Base ‘ 𝑉 ) ) | 
						
							| 68 | 67 | adantr | ⊢ ( ( ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  ∧  𝑙  ∈  𝐾 )  ∧  𝑥  =  ( 𝑙  ·  𝑋 ) )  →  ( 𝑙  ·  𝑋 )  ∈  ( Base ‘ 𝑉 ) ) | 
						
							| 69 | 62 68 | eqeltrd | ⊢ ( ( ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  ∧  𝑙  ∈  𝐾 )  ∧  𝑥  =  ( 𝑙  ·  𝑋 ) )  →  𝑥  ∈  ( Base ‘ 𝑉 ) ) | 
						
							| 70 | 69 | rexlimdva2 | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  ( ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 )  →  𝑥  ∈  ( Base ‘ 𝑉 ) ) ) | 
						
							| 71 | 70 | pm4.71rd | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  ( ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 )  ↔  ( 𝑥  ∈  ( Base ‘ 𝑉 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) ) ) | 
						
							| 72 | 71 | abbidv | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  { 𝑥  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  =  { 𝑥  ∣  ( 𝑥  ∈  ( Base ‘ 𝑉 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } ) | 
						
							| 73 |  | df-rab | ⊢ { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  =  { 𝑥  ∣  ( 𝑥  ∈  ( Base ‘ 𝑉 )  ∧  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) ) } | 
						
							| 74 | 72 73 | eqtr4di | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  { 𝑥  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  =  { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) } ) | 
						
							| 75 | 61 74 | eqtrd | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  ( 𝑁 ‘ { 𝑋 } )  =  { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) } ) | 
						
							| 76 | 75 | difeq1d | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  ( ( 𝑁 ‘ { 𝑋 } )  ∖  { ( 0g ‘ 𝑉 ) } )  =  ( { 𝑥  ∈  ( Base ‘ 𝑉 )  ∣  ∃ 𝑙  ∈  𝐾 𝑥  =  ( 𝑙  ·  𝑋 ) }  ∖  { ( 0g ‘ 𝑉 ) } ) ) | 
						
							| 77 | 48 54 76 | 3eqtr4d | ⊢ ( ( 𝑉  ∈  LVec  ∧  𝑋  ∈  𝐵 )  →  [ 𝑋 ]  ∼   =  ( ( 𝑁 ‘ { 𝑋 } )  ∖  { ( 0g ‘ 𝑉 ) } ) ) |