| Step | Hyp | Ref | Expression | 
						
							| 1 |  | tposssxp | ⊢ tpos  𝐹  ⊆  ( ( ◡ dom  𝐹  ∪  { ∅ } )  ×  ran  𝐹 ) | 
						
							| 2 |  | dmexg | ⊢ ( 𝐹  ∈  𝑉  →  dom  𝐹  ∈  V ) | 
						
							| 3 |  | cnvexg | ⊢ ( dom  𝐹  ∈  V  →  ◡ dom  𝐹  ∈  V ) | 
						
							| 4 | 2 3 | syl | ⊢ ( 𝐹  ∈  𝑉  →  ◡ dom  𝐹  ∈  V ) | 
						
							| 5 |  | p0ex | ⊢ { ∅ }  ∈  V | 
						
							| 6 |  | unexg | ⊢ ( ( ◡ dom  𝐹  ∈  V  ∧  { ∅ }  ∈  V )  →  ( ◡ dom  𝐹  ∪  { ∅ } )  ∈  V ) | 
						
							| 7 | 4 5 6 | sylancl | ⊢ ( 𝐹  ∈  𝑉  →  ( ◡ dom  𝐹  ∪  { ∅ } )  ∈  V ) | 
						
							| 8 |  | rnexg | ⊢ ( 𝐹  ∈  𝑉  →  ran  𝐹  ∈  V ) | 
						
							| 9 | 7 8 | xpexd | ⊢ ( 𝐹  ∈  𝑉  →  ( ( ◡ dom  𝐹  ∪  { ∅ } )  ×  ran  𝐹 )  ∈  V ) | 
						
							| 10 |  | ssexg | ⊢ ( ( tpos  𝐹  ⊆  ( ( ◡ dom  𝐹  ∪  { ∅ } )  ×  ran  𝐹 )  ∧  ( ( ◡ dom  𝐹  ∪  { ∅ } )  ×  ran  𝐹 )  ∈  V )  →  tpos  𝐹  ∈  V ) | 
						
							| 11 | 1 9 10 | sylancr | ⊢ ( 𝐹  ∈  𝑉  →  tpos  𝐹  ∈  V ) |