| Step | Hyp | Ref | Expression | 
						
							| 1 |  | mapdh.q | ⊢ 𝑄  =  ( 0g ‘ 𝐶 ) | 
						
							| 2 |  | mapdh.i | ⊢ 𝐼  =  ( 𝑥  ∈  V  ↦  if ( ( 2nd  ‘ 𝑥 )  =   0  ,  𝑄 ,  ( ℩ ℎ  ∈  𝐷 ( ( 𝑀 ‘ ( 𝑁 ‘ { ( 2nd  ‘ 𝑥 ) } ) )  =  ( 𝐽 ‘ { ℎ } )  ∧  ( 𝑀 ‘ ( 𝑁 ‘ { ( ( 1st  ‘ ( 1st  ‘ 𝑥 ) )  −  ( 2nd  ‘ 𝑥 ) ) } ) )  =  ( 𝐽 ‘ { ( ( 2nd  ‘ ( 1st  ‘ 𝑥 ) ) 𝑅 ℎ ) } ) ) ) ) ) | 
						
							| 3 |  | mapdh.h | ⊢ 𝐻  =  ( LHyp ‘ 𝐾 ) | 
						
							| 4 |  | mapdh.m | ⊢ 𝑀  =  ( ( mapd ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 5 |  | mapdh.u | ⊢ 𝑈  =  ( ( DVecH ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 6 |  | mapdh.v | ⊢ 𝑉  =  ( Base ‘ 𝑈 ) | 
						
							| 7 |  | mapdh.s | ⊢  −   =  ( -g ‘ 𝑈 ) | 
						
							| 8 |  | mapdhc.o | ⊢  0   =  ( 0g ‘ 𝑈 ) | 
						
							| 9 |  | mapdh.n | ⊢ 𝑁  =  ( LSpan ‘ 𝑈 ) | 
						
							| 10 |  | mapdh.c | ⊢ 𝐶  =  ( ( LCDual ‘ 𝐾 ) ‘ 𝑊 ) | 
						
							| 11 |  | mapdh.d | ⊢ 𝐷  =  ( Base ‘ 𝐶 ) | 
						
							| 12 |  | mapdh.r | ⊢ 𝑅  =  ( -g ‘ 𝐶 ) | 
						
							| 13 |  | mapdh.j | ⊢ 𝐽  =  ( LSpan ‘ 𝐶 ) | 
						
							| 14 |  | mapdh.k | ⊢ ( 𝜑  →  ( 𝐾  ∈  HL  ∧  𝑊  ∈  𝐻 ) ) | 
						
							| 15 |  | mapdhc.f | ⊢ ( 𝜑  →  𝐹  ∈  𝐷 ) | 
						
							| 16 |  | mapdh.mn | ⊢ ( 𝜑  →  ( 𝑀 ‘ ( 𝑁 ‘ { 𝑋 } ) )  =  ( 𝐽 ‘ { 𝐹 } ) ) | 
						
							| 17 |  | mapdhcl.x | ⊢ ( 𝜑  →  𝑋  ∈  ( 𝑉  ∖  {  0  } ) ) | 
						
							| 18 |  | mapdh.p | ⊢  +   =  ( +g ‘ 𝑈 ) | 
						
							| 19 |  | mapdh.a | ⊢  ✚   =  ( +g ‘ 𝐶 ) | 
						
							| 20 |  | mapdh6d.xn | ⊢ ( 𝜑  →  ¬  𝑋  ∈  ( 𝑁 ‘ { 𝑌 ,  𝑍 } ) ) | 
						
							| 21 |  | mapdh6d.yz | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑌 } )  =  ( 𝑁 ‘ { 𝑍 } ) ) | 
						
							| 22 |  | mapdh6d.y | ⊢ ( 𝜑  →  𝑌  ∈  ( 𝑉  ∖  {  0  } ) ) | 
						
							| 23 |  | mapdh6d.z | ⊢ ( 𝜑  →  𝑍  ∈  ( 𝑉  ∖  {  0  } ) ) | 
						
							| 24 |  | mapdh6d.w | ⊢ ( 𝜑  →  𝑤  ∈  ( 𝑉  ∖  {  0  } ) ) | 
						
							| 25 |  | mapdh6d.wn | ⊢ ( 𝜑  →  ¬  𝑤  ∈  ( 𝑁 ‘ { 𝑋 ,  𝑌 } ) ) | 
						
							| 26 | 3 5 14 | dvhlmod | ⊢ ( 𝜑  →  𝑈  ∈  LMod ) | 
						
							| 27 | 24 | eldifad | ⊢ ( 𝜑  →  𝑤  ∈  𝑉 ) | 
						
							| 28 | 22 | eldifad | ⊢ ( 𝜑  →  𝑌  ∈  𝑉 ) | 
						
							| 29 | 6 18 | lmodvacl | ⊢ ( ( 𝑈  ∈  LMod  ∧  𝑤  ∈  𝑉  ∧  𝑌  ∈  𝑉 )  →  ( 𝑤  +  𝑌 )  ∈  𝑉 ) | 
						
							| 30 | 26 27 28 29 | syl3anc | ⊢ ( 𝜑  →  ( 𝑤  +  𝑌 )  ∈  𝑉 ) | 
						
							| 31 | 3 5 14 | dvhlvec | ⊢ ( 𝜑  →  𝑈  ∈  LVec ) | 
						
							| 32 | 17 | eldifad | ⊢ ( 𝜑  →  𝑋  ∈  𝑉 ) | 
						
							| 33 | 6 9 31 27 32 28 25 | lspindpi | ⊢ ( 𝜑  →  ( ( 𝑁 ‘ { 𝑤 } )  ≠  ( 𝑁 ‘ { 𝑋 } )  ∧  ( 𝑁 ‘ { 𝑤 } )  ≠  ( 𝑁 ‘ { 𝑌 } ) ) ) | 
						
							| 34 | 33 | simprd | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑤 } )  ≠  ( 𝑁 ‘ { 𝑌 } ) ) | 
						
							| 35 | 6 18 8 9 26 27 28 34 | lmodindp1 | ⊢ ( 𝜑  →  ( 𝑤  +  𝑌 )  ≠   0  ) | 
						
							| 36 |  | eldifsn | ⊢ ( ( 𝑤  +  𝑌 )  ∈  ( 𝑉  ∖  {  0  } )  ↔  ( ( 𝑤  +  𝑌 )  ∈  𝑉  ∧  ( 𝑤  +  𝑌 )  ≠   0  ) ) | 
						
							| 37 | 30 35 36 | sylanbrc | ⊢ ( 𝜑  →  ( 𝑤  +  𝑌 )  ∈  ( 𝑉  ∖  {  0  } ) ) | 
						
							| 38 | 23 | eldifad | ⊢ ( 𝜑  →  𝑍  ∈  𝑉 ) | 
						
							| 39 | 6 9 31 32 28 38 20 | lspindpi | ⊢ ( 𝜑  →  ( ( 𝑁 ‘ { 𝑋 } )  ≠  ( 𝑁 ‘ { 𝑌 } )  ∧  ( 𝑁 ‘ { 𝑋 } )  ≠  ( 𝑁 ‘ { 𝑍 } ) ) ) | 
						
							| 40 | 39 | simpld | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑋 } )  ≠  ( 𝑁 ‘ { 𝑌 } ) ) | 
						
							| 41 | 6 18 8 9 31 17 22 23 24 21 40 25 | mapdindp3 | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑋 } )  ≠  ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) } ) ) | 
						
							| 42 | 6 18 8 9 31 17 22 23 24 21 40 25 | mapdindp4 | ⊢ ( 𝜑  →  ¬  𝑍  ∈  ( 𝑁 ‘ { 𝑋 ,  ( 𝑤  +  𝑌 ) } ) ) | 
						
							| 43 | 6 8 9 31 17 30 38 41 42 | lspindp1 | ⊢ ( 𝜑  →  ( ( 𝑁 ‘ { 𝑍 } )  ≠  ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) } )  ∧  ¬  𝑋  ∈  ( 𝑁 ‘ { 𝑍 ,  ( 𝑤  +  𝑌 ) } ) ) ) | 
						
							| 44 | 43 | simprd | ⊢ ( 𝜑  →  ¬  𝑋  ∈  ( 𝑁 ‘ { 𝑍 ,  ( 𝑤  +  𝑌 ) } ) ) | 
						
							| 45 |  | prcom | ⊢ { ( 𝑤  +  𝑌 ) ,  𝑍 }  =  { 𝑍 ,  ( 𝑤  +  𝑌 ) } | 
						
							| 46 | 45 | fveq2i | ⊢ ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) ,  𝑍 } )  =  ( 𝑁 ‘ { 𝑍 ,  ( 𝑤  +  𝑌 ) } ) | 
						
							| 47 | 46 | eleq2i | ⊢ ( 𝑋  ∈  ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) ,  𝑍 } )  ↔  𝑋  ∈  ( 𝑁 ‘ { 𝑍 ,  ( 𝑤  +  𝑌 ) } ) ) | 
						
							| 48 | 44 47 | sylnibr | ⊢ ( 𝜑  →  ¬  𝑋  ∈  ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) ,  𝑍 } ) ) | 
						
							| 49 | 6 9 31 38 32 30 42 | lspindpi | ⊢ ( 𝜑  →  ( ( 𝑁 ‘ { 𝑍 } )  ≠  ( 𝑁 ‘ { 𝑋 } )  ∧  ( 𝑁 ‘ { 𝑍 } )  ≠  ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) } ) ) ) | 
						
							| 50 | 49 | simprd | ⊢ ( 𝜑  →  ( 𝑁 ‘ { 𝑍 } )  ≠  ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) } ) ) | 
						
							| 51 | 50 | necomd | ⊢ ( 𝜑  →  ( 𝑁 ‘ { ( 𝑤  +  𝑌 ) } )  ≠  ( 𝑁 ‘ { 𝑍 } ) ) | 
						
							| 52 |  | eqidd | ⊢ ( 𝜑  →  ( 𝐼 ‘ 〈 𝑋 ,  𝐹 ,  ( 𝑤  +  𝑌 ) 〉 )  =  ( 𝐼 ‘ 〈 𝑋 ,  𝐹 ,  ( 𝑤  +  𝑌 ) 〉 ) ) | 
						
							| 53 |  | eqidd | ⊢ ( 𝜑  →  ( 𝐼 ‘ 〈 𝑋 ,  𝐹 ,  𝑍 〉 )  =  ( 𝐼 ‘ 〈 𝑋 ,  𝐹 ,  𝑍 〉 ) ) | 
						
							| 54 | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 37 23 48 51 52 53 | mapdh6aN | ⊢ ( 𝜑  →  ( 𝐼 ‘ 〈 𝑋 ,  𝐹 ,  ( ( 𝑤  +  𝑌 )  +  𝑍 ) 〉 )  =  ( ( 𝐼 ‘ 〈 𝑋 ,  𝐹 ,  ( 𝑤  +  𝑌 ) 〉 )  ✚  ( 𝐼 ‘ 〈 𝑋 ,  𝐹 ,  𝑍 〉 ) ) ) |