| Step | Hyp | Ref | Expression | 
						
							| 1 |  | nonbool.1 | ⊢ 𝐴  ∈   ℋ | 
						
							| 2 |  | nonbool.2 | ⊢ 𝐵  ∈   ℋ | 
						
							| 3 |  | nonbool.3 | ⊢ 𝐹  =  ( span ‘ { 𝐴 } ) | 
						
							| 4 |  | nonbool.4 | ⊢ 𝐺  =  ( span ‘ { 𝐵 } ) | 
						
							| 5 |  | nonbool.5 | ⊢ 𝐻  =  ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } ) | 
						
							| 6 | 1 2 | hvaddcli | ⊢ ( 𝐴  +ℎ  𝐵 )  ∈   ℋ | 
						
							| 7 |  | spansnid | ⊢ ( ( 𝐴  +ℎ  𝐵 )  ∈   ℋ  →  ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } ) ) | 
						
							| 8 | 6 7 | ax-mp | ⊢ ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } ) | 
						
							| 9 | 8 5 | eleqtrri | ⊢ ( 𝐴  +ℎ  𝐵 )  ∈  𝐻 | 
						
							| 10 | 1 | spansnchi | ⊢ ( span ‘ { 𝐴 } )  ∈   Cℋ | 
						
							| 11 | 10 | chshii | ⊢ ( span ‘ { 𝐴 } )  ∈   Sℋ | 
						
							| 12 | 3 11 | eqeltri | ⊢ 𝐹  ∈   Sℋ | 
						
							| 13 | 2 | spansnchi | ⊢ ( span ‘ { 𝐵 } )  ∈   Cℋ | 
						
							| 14 | 13 | chshii | ⊢ ( span ‘ { 𝐵 } )  ∈   Sℋ | 
						
							| 15 | 4 14 | eqeltri | ⊢ 𝐺  ∈   Sℋ | 
						
							| 16 | 12 15 | shsleji | ⊢ ( 𝐹  +ℋ  𝐺 )  ⊆  ( 𝐹  ∨ℋ  𝐺 ) | 
						
							| 17 |  | spansnid | ⊢ ( 𝐴  ∈   ℋ  →  𝐴  ∈  ( span ‘ { 𝐴 } ) ) | 
						
							| 18 | 1 17 | ax-mp | ⊢ 𝐴  ∈  ( span ‘ { 𝐴 } ) | 
						
							| 19 | 18 3 | eleqtrri | ⊢ 𝐴  ∈  𝐹 | 
						
							| 20 |  | spansnid | ⊢ ( 𝐵  ∈   ℋ  →  𝐵  ∈  ( span ‘ { 𝐵 } ) ) | 
						
							| 21 | 2 20 | ax-mp | ⊢ 𝐵  ∈  ( span ‘ { 𝐵 } ) | 
						
							| 22 | 21 4 | eleqtrri | ⊢ 𝐵  ∈  𝐺 | 
						
							| 23 | 12 15 | shsvai | ⊢ ( ( 𝐴  ∈  𝐹  ∧  𝐵  ∈  𝐺 )  →  ( 𝐴  +ℎ  𝐵 )  ∈  ( 𝐹  +ℋ  𝐺 ) ) | 
						
							| 24 | 19 22 23 | mp2an | ⊢ ( 𝐴  +ℎ  𝐵 )  ∈  ( 𝐹  +ℋ  𝐺 ) | 
						
							| 25 | 16 24 | sselii | ⊢ ( 𝐴  +ℎ  𝐵 )  ∈  ( 𝐹  ∨ℋ  𝐺 ) | 
						
							| 26 |  | elin | ⊢ ( ( 𝐴  +ℎ  𝐵 )  ∈  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  ↔  ( ( 𝐴  +ℎ  𝐵 )  ∈  𝐻  ∧  ( 𝐴  +ℎ  𝐵 )  ∈  ( 𝐹  ∨ℋ  𝐺 ) ) ) | 
						
							| 27 | 9 25 26 | mpbir2an | ⊢ ( 𝐴  +ℎ  𝐵 )  ∈  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) ) | 
						
							| 28 |  | eleq2 | ⊢ ( ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ  →  ( ( 𝐴  +ℎ  𝐵 )  ∈  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  ↔  ( 𝐴  +ℎ  𝐵 )  ∈  0ℋ ) ) | 
						
							| 29 | 27 28 | mpbii | ⊢ ( ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ  →  ( 𝐴  +ℎ  𝐵 )  ∈  0ℋ ) | 
						
							| 30 |  | elch0 | ⊢ ( ( 𝐴  +ℎ  𝐵 )  ∈  0ℋ  ↔  ( 𝐴  +ℎ  𝐵 )  =  0ℎ ) | 
						
							| 31 | 29 30 | sylib | ⊢ ( ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ  →  ( 𝐴  +ℎ  𝐵 )  =  0ℎ ) | 
						
							| 32 |  | ch0 | ⊢ ( ( span ‘ { 𝐴 } )  ∈   Cℋ   →  0ℎ  ∈  ( span ‘ { 𝐴 } ) ) | 
						
							| 33 | 10 32 | ax-mp | ⊢ 0ℎ  ∈  ( span ‘ { 𝐴 } ) | 
						
							| 34 | 31 33 | eqeltrdi | ⊢ ( ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ  →  ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐴 } ) ) | 
						
							| 35 | 3 | eleq2i | ⊢ ( 𝐵  ∈  𝐹  ↔  𝐵  ∈  ( span ‘ { 𝐴 } ) ) | 
						
							| 36 |  | sumspansn | ⊢ ( ( 𝐴  ∈   ℋ  ∧  𝐵  ∈   ℋ )  →  ( ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐴 } )  ↔  𝐵  ∈  ( span ‘ { 𝐴 } ) ) ) | 
						
							| 37 | 1 2 36 | mp2an | ⊢ ( ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐴 } )  ↔  𝐵  ∈  ( span ‘ { 𝐴 } ) ) | 
						
							| 38 | 35 37 | bitr4i | ⊢ ( 𝐵  ∈  𝐹  ↔  ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐴 } ) ) | 
						
							| 39 | 34 38 | sylibr | ⊢ ( ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ  →  𝐵  ∈  𝐹 ) | 
						
							| 40 | 39 | con3i | ⊢ ( ¬  𝐵  ∈  𝐹  →  ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ ) | 
						
							| 41 | 40 | adantl | ⊢ ( ( ¬  𝐴  ∈  𝐺  ∧  ¬  𝐵  ∈  𝐹 )  →  ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ ) | 
						
							| 42 | 5 3 | ineq12i | ⊢ ( 𝐻  ∩  𝐹 )  =  ( ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } )  ∩  ( span ‘ { 𝐴 } ) ) | 
						
							| 43 | 6 1 | spansnm0i | ⊢ ( ¬  ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐴 } )  →  ( ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } )  ∩  ( span ‘ { 𝐴 } ) )  =  0ℋ ) | 
						
							| 44 | 38 43 | sylnbi | ⊢ ( ¬  𝐵  ∈  𝐹  →  ( ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } )  ∩  ( span ‘ { 𝐴 } ) )  =  0ℋ ) | 
						
							| 45 | 42 44 | eqtrid | ⊢ ( ¬  𝐵  ∈  𝐹  →  ( 𝐻  ∩  𝐹 )  =  0ℋ ) | 
						
							| 46 | 5 4 | ineq12i | ⊢ ( 𝐻  ∩  𝐺 )  =  ( ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } )  ∩  ( span ‘ { 𝐵 } ) ) | 
						
							| 47 |  | sumspansn | ⊢ ( ( 𝐵  ∈   ℋ  ∧  𝐴  ∈   ℋ )  →  ( ( 𝐵  +ℎ  𝐴 )  ∈  ( span ‘ { 𝐵 } )  ↔  𝐴  ∈  ( span ‘ { 𝐵 } ) ) ) | 
						
							| 48 | 2 1 47 | mp2an | ⊢ ( ( 𝐵  +ℎ  𝐴 )  ∈  ( span ‘ { 𝐵 } )  ↔  𝐴  ∈  ( span ‘ { 𝐵 } ) ) | 
						
							| 49 | 1 2 | hvcomi | ⊢ ( 𝐴  +ℎ  𝐵 )  =  ( 𝐵  +ℎ  𝐴 ) | 
						
							| 50 | 49 | eleq1i | ⊢ ( ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐵 } )  ↔  ( 𝐵  +ℎ  𝐴 )  ∈  ( span ‘ { 𝐵 } ) ) | 
						
							| 51 | 4 | eleq2i | ⊢ ( 𝐴  ∈  𝐺  ↔  𝐴  ∈  ( span ‘ { 𝐵 } ) ) | 
						
							| 52 | 48 50 51 | 3bitr4ri | ⊢ ( 𝐴  ∈  𝐺  ↔  ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐵 } ) ) | 
						
							| 53 | 6 2 | spansnm0i | ⊢ ( ¬  ( 𝐴  +ℎ  𝐵 )  ∈  ( span ‘ { 𝐵 } )  →  ( ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } )  ∩  ( span ‘ { 𝐵 } ) )  =  0ℋ ) | 
						
							| 54 | 52 53 | sylnbi | ⊢ ( ¬  𝐴  ∈  𝐺  →  ( ( span ‘ { ( 𝐴  +ℎ  𝐵 ) } )  ∩  ( span ‘ { 𝐵 } ) )  =  0ℋ ) | 
						
							| 55 | 46 54 | eqtrid | ⊢ ( ¬  𝐴  ∈  𝐺  →  ( 𝐻  ∩  𝐺 )  =  0ℋ ) | 
						
							| 56 | 45 55 | oveqan12rd | ⊢ ( ( ¬  𝐴  ∈  𝐺  ∧  ¬  𝐵  ∈  𝐹 )  →  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  =  ( 0ℋ  ∨ℋ  0ℋ ) ) | 
						
							| 57 |  | h0elch | ⊢ 0ℋ  ∈   Cℋ | 
						
							| 58 | 57 | chj0i | ⊢ ( 0ℋ  ∨ℋ  0ℋ )  =  0ℋ | 
						
							| 59 | 56 58 | eqtrdi | ⊢ ( ( ¬  𝐴  ∈  𝐺  ∧  ¬  𝐵  ∈  𝐹 )  →  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  =  0ℋ ) | 
						
							| 60 |  | eqeq2 | ⊢ ( ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  =  0ℋ  →  ( ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  ↔  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ ) ) | 
						
							| 61 | 60 | notbid | ⊢ ( ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  =  0ℋ  →  ( ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  ↔  ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ ) ) | 
						
							| 62 | 61 | biimparc | ⊢ ( ( ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  0ℋ  ∧  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  =  0ℋ )  →  ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) ) ) | 
						
							| 63 | 41 59 62 | syl2anc | ⊢ ( ( ¬  𝐴  ∈  𝐺  ∧  ¬  𝐵  ∈  𝐹 )  →  ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) ) ) | 
						
							| 64 |  | ioran | ⊢ ( ¬  ( 𝐴  ∈  𝐺  ∨  𝐵  ∈  𝐹 )  ↔  ( ¬  𝐴  ∈  𝐺  ∧  ¬  𝐵  ∈  𝐹 ) ) | 
						
							| 65 |  | df-ne | ⊢ ( ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  ≠  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) )  ↔  ¬  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  =  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) ) ) | 
						
							| 66 | 63 64 65 | 3imtr4i | ⊢ ( ¬  ( 𝐴  ∈  𝐺  ∨  𝐵  ∈  𝐹 )  →  ( 𝐻  ∩  ( 𝐹  ∨ℋ  𝐺 ) )  ≠  ( ( 𝐻  ∩  𝐹 )  ∨ℋ  ( 𝐻  ∩  𝐺 ) ) ) |