| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 0oval.1 | ⊢ 𝑋  =  ( BaseSet ‘ 𝑈 ) | 
						
							| 2 |  | 0oval.6 | ⊢ 𝑍  =  ( 0vec ‘ 𝑊 ) | 
						
							| 3 |  | 0oval.0 | ⊢ 𝑂  =  ( 𝑈  0op  𝑊 ) | 
						
							| 4 |  | fveq2 | ⊢ ( 𝑢  =  𝑈  →  ( BaseSet ‘ 𝑢 )  =  ( BaseSet ‘ 𝑈 ) ) | 
						
							| 5 | 4 1 | eqtr4di | ⊢ ( 𝑢  =  𝑈  →  ( BaseSet ‘ 𝑢 )  =  𝑋 ) | 
						
							| 6 | 5 | xpeq1d | ⊢ ( 𝑢  =  𝑈  →  ( ( BaseSet ‘ 𝑢 )  ×  { ( 0vec ‘ 𝑤 ) } )  =  ( 𝑋  ×  { ( 0vec ‘ 𝑤 ) } ) ) | 
						
							| 7 |  | fveq2 | ⊢ ( 𝑤  =  𝑊  →  ( 0vec ‘ 𝑤 )  =  ( 0vec ‘ 𝑊 ) ) | 
						
							| 8 | 7 2 | eqtr4di | ⊢ ( 𝑤  =  𝑊  →  ( 0vec ‘ 𝑤 )  =  𝑍 ) | 
						
							| 9 | 8 | sneqd | ⊢ ( 𝑤  =  𝑊  →  { ( 0vec ‘ 𝑤 ) }  =  { 𝑍 } ) | 
						
							| 10 | 9 | xpeq2d | ⊢ ( 𝑤  =  𝑊  →  ( 𝑋  ×  { ( 0vec ‘ 𝑤 ) } )  =  ( 𝑋  ×  { 𝑍 } ) ) | 
						
							| 11 |  | df-0o | ⊢  0op   =  ( 𝑢  ∈  NrmCVec ,  𝑤  ∈  NrmCVec  ↦  ( ( BaseSet ‘ 𝑢 )  ×  { ( 0vec ‘ 𝑤 ) } ) ) | 
						
							| 12 | 1 | fvexi | ⊢ 𝑋  ∈  V | 
						
							| 13 |  | snex | ⊢ { 𝑍 }  ∈  V | 
						
							| 14 | 12 13 | xpex | ⊢ ( 𝑋  ×  { 𝑍 } )  ∈  V | 
						
							| 15 | 6 10 11 14 | ovmpo | ⊢ ( ( 𝑈  ∈  NrmCVec  ∧  𝑊  ∈  NrmCVec )  →  ( 𝑈  0op  𝑊 )  =  ( 𝑋  ×  { 𝑍 } ) ) | 
						
							| 16 | 3 15 | eqtrid | ⊢ ( ( 𝑈  ∈  NrmCVec  ∧  𝑊  ∈  NrmCVec )  →  𝑂  =  ( 𝑋  ×  { 𝑍 } ) ) |