| Step | Hyp | Ref | Expression | 
						
							| 1 |  | lspprat.v | ⊢ 𝑉  =  ( Base ‘ 𝑊 ) | 
						
							| 2 |  | lspprat.s | ⊢ 𝑆  =  ( LSubSp ‘ 𝑊 ) | 
						
							| 3 |  | lspprat.n | ⊢ 𝑁  =  ( LSpan ‘ 𝑊 ) | 
						
							| 4 |  | lspprat.w | ⊢ ( 𝜑  →  𝑊  ∈  LVec ) | 
						
							| 5 |  | lspprat.u | ⊢ ( 𝜑  →  𝑈  ∈  𝑆 ) | 
						
							| 6 |  | lspprat.x | ⊢ ( 𝜑  →  𝑋  ∈  𝑉 ) | 
						
							| 7 |  | lspprat.y | ⊢ ( 𝜑  →  𝑌  ∈  𝑉 ) | 
						
							| 8 |  | lspprat.p | ⊢ ( 𝜑  →  𝑈  ⊊  ( 𝑁 ‘ { 𝑋 ,  𝑌 } ) ) | 
						
							| 9 |  | lsppratlem1.o | ⊢  0   =  ( 0g ‘ 𝑊 ) | 
						
							| 10 |  | lsppratlem1.x2 | ⊢ ( 𝜑  →  𝑥  ∈  ( 𝑈  ∖  {  0  } ) ) | 
						
							| 11 |  | lsppratlem1.y2 | ⊢ ( 𝜑  →  𝑦  ∈  ( 𝑈  ∖  ( 𝑁 ‘ { 𝑥 } ) ) ) | 
						
							| 12 |  | lsppratlem4.x3 | ⊢ ( 𝜑  →  𝑋  ∈  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 13 |  | lveclmod | ⊢ ( 𝑊  ∈  LVec  →  𝑊  ∈  LMod ) | 
						
							| 14 | 4 13 | syl | ⊢ ( 𝜑  →  𝑊  ∈  LMod ) | 
						
							| 15 | 1 2 | lssss | ⊢ ( 𝑈  ∈  𝑆  →  𝑈  ⊆  𝑉 ) | 
						
							| 16 | 5 15 | syl | ⊢ ( 𝜑  →  𝑈  ⊆  𝑉 ) | 
						
							| 17 | 16 | ssdifssd | ⊢ ( 𝜑  →  ( 𝑈  ∖  {  0  } )  ⊆  𝑉 ) | 
						
							| 18 | 17 10 | sseldd | ⊢ ( 𝜑  →  𝑥  ∈  𝑉 ) | 
						
							| 19 | 16 | ssdifssd | ⊢ ( 𝜑  →  ( 𝑈  ∖  ( 𝑁 ‘ { 𝑥 } ) )  ⊆  𝑉 ) | 
						
							| 20 | 19 11 | sseldd | ⊢ ( 𝜑  →  𝑦  ∈  𝑉 ) | 
						
							| 21 | 1 2 3 14 18 20 | lspprcl | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑥 ,  𝑦 } )  ∈  𝑆 ) | 
						
							| 22 |  | df-pr | ⊢ { 𝑥 ,  𝑌 }  =  ( { 𝑥 }  ∪  { 𝑌 } ) | 
						
							| 23 |  | snsspr1 | ⊢ { 𝑥 }  ⊆  { 𝑥 ,  𝑦 } | 
						
							| 24 | 18 20 | prssd | ⊢ ( 𝜑  →  { 𝑥 ,  𝑦 }  ⊆  𝑉 ) | 
						
							| 25 | 1 3 | lspssid | ⊢ ( ( 𝑊  ∈  LMod  ∧  { 𝑥 ,  𝑦 }  ⊆  𝑉 )  →  { 𝑥 ,  𝑦 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 26 | 14 24 25 | syl2anc | ⊢ ( 𝜑  →  { 𝑥 ,  𝑦 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 27 | 23 26 | sstrid | ⊢ ( 𝜑  →  { 𝑥 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 28 | 18 | snssd | ⊢ ( 𝜑  →  { 𝑥 }  ⊆  𝑉 ) | 
						
							| 29 | 8 | pssssd | ⊢ ( 𝜑  →  𝑈  ⊆  ( 𝑁 ‘ { 𝑋 ,  𝑌 } ) ) | 
						
							| 30 | 1 2 3 14 18 7 | lspprcl | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑥 ,  𝑌 } )  ∈  𝑆 ) | 
						
							| 31 |  | df-pr | ⊢ { 𝑋 ,  𝑌 }  =  ( { 𝑋 }  ∪  { 𝑌 } ) | 
						
							| 32 | 12 | snssd | ⊢ ( 𝜑  →  { 𝑋 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 33 |  | snsspr2 | ⊢ { 𝑌 }  ⊆  { 𝑥 ,  𝑌 } | 
						
							| 34 | 18 7 | prssd | ⊢ ( 𝜑  →  { 𝑥 ,  𝑌 }  ⊆  𝑉 ) | 
						
							| 35 | 1 3 | lspssid | ⊢ ( ( 𝑊  ∈  LMod  ∧  { 𝑥 ,  𝑌 }  ⊆  𝑉 )  →  { 𝑥 ,  𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 36 | 14 34 35 | syl2anc | ⊢ ( 𝜑  →  { 𝑥 ,  𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 37 | 33 36 | sstrid | ⊢ ( 𝜑  →  { 𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 38 | 32 37 | unssd | ⊢ ( 𝜑  →  ( { 𝑋 }  ∪  { 𝑌 } )  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 39 | 31 38 | eqsstrid | ⊢ ( 𝜑  →  { 𝑋 ,  𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 40 | 2 3 | lspssp | ⊢ ( ( 𝑊  ∈  LMod  ∧  ( 𝑁 ‘ { 𝑥 ,  𝑌 } )  ∈  𝑆  ∧  { 𝑋 ,  𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) )  →  ( 𝑁 ‘ { 𝑋 ,  𝑌 } )  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 41 | 14 30 39 40 | syl3anc | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑋 ,  𝑌 } )  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 42 | 29 41 | sstrd | ⊢ ( 𝜑  →  𝑈  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑌 } ) ) | 
						
							| 43 | 22 | fveq2i | ⊢ ( 𝑁 ‘ { 𝑥 ,  𝑌 } )  =  ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑌 } ) ) | 
						
							| 44 | 42 43 | sseqtrdi | ⊢ ( 𝜑  →  𝑈  ⊆  ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑌 } ) ) ) | 
						
							| 45 | 44 | ssdifd | ⊢ ( 𝜑  →  ( 𝑈  ∖  ( 𝑁 ‘ { 𝑥 } ) )  ⊆  ( ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑌 } ) )  ∖  ( 𝑁 ‘ { 𝑥 } ) ) ) | 
						
							| 46 | 45 11 | sseldd | ⊢ ( 𝜑  →  𝑦  ∈  ( ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑌 } ) )  ∖  ( 𝑁 ‘ { 𝑥 } ) ) ) | 
						
							| 47 | 1 2 3 | lspsolv | ⊢ ( ( 𝑊  ∈  LVec  ∧  ( { 𝑥 }  ⊆  𝑉  ∧  𝑌  ∈  𝑉  ∧  𝑦  ∈  ( ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑌 } ) )  ∖  ( 𝑁 ‘ { 𝑥 } ) ) ) )  →  𝑌  ∈  ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑦 } ) ) ) | 
						
							| 48 | 4 28 7 46 47 | syl13anc | ⊢ ( 𝜑  →  𝑌  ∈  ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑦 } ) ) ) | 
						
							| 49 |  | df-pr | ⊢ { 𝑥 ,  𝑦 }  =  ( { 𝑥 }  ∪  { 𝑦 } ) | 
						
							| 50 | 49 | fveq2i | ⊢ ( 𝑁 ‘ { 𝑥 ,  𝑦 } )  =  ( 𝑁 ‘ ( { 𝑥 }  ∪  { 𝑦 } ) ) | 
						
							| 51 | 48 50 | eleqtrrdi | ⊢ ( 𝜑  →  𝑌  ∈  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 52 | 51 | snssd | ⊢ ( 𝜑  →  { 𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 53 | 27 52 | unssd | ⊢ ( 𝜑  →  ( { 𝑥 }  ∪  { 𝑌 } )  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 54 | 22 53 | eqsstrid | ⊢ ( 𝜑  →  { 𝑥 ,  𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 55 | 2 3 | lspssp | ⊢ ( ( 𝑊  ∈  LMod  ∧  ( 𝑁 ‘ { 𝑥 ,  𝑦 } )  ∈  𝑆  ∧  { 𝑥 ,  𝑌 }  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) )  →  ( 𝑁 ‘ { 𝑥 ,  𝑌 } )  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 56 | 14 21 54 55 | syl3anc | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑥 ,  𝑌 } )  ⊆  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 57 | 56 12 | sseldd | ⊢ ( 𝜑  →  𝑋  ∈  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) | 
						
							| 58 | 57 51 | jca | ⊢ ( 𝜑  →  ( 𝑋  ∈  ( 𝑁 ‘ { 𝑥 ,  𝑦 } )  ∧  𝑌  ∈  ( 𝑁 ‘ { 𝑥 ,  𝑦 } ) ) ) |