| Step | Hyp | Ref | Expression | 
						
							| 1 |  | 0ex | ⊢ ∅  ∈  V | 
						
							| 2 |  | satefv | ⊢ ( ( ∅  ∈  V  ∧  𝑈  ∈  𝑉 )  →  ( ∅  Sat∈  𝑈 )  =  ( ( ( ∅  Sat  (  E   ∩  ( ∅  ×  ∅ ) ) ) ‘ ω ) ‘ 𝑈 ) ) | 
						
							| 3 | 1 2 | mpan | ⊢ ( 𝑈  ∈  𝑉  →  ( ∅  Sat∈  𝑈 )  =  ( ( ( ∅  Sat  (  E   ∩  ( ∅  ×  ∅ ) ) ) ‘ ω ) ‘ 𝑈 ) ) | 
						
							| 4 |  | xp0 | ⊢ ( ∅  ×  ∅ )  =  ∅ | 
						
							| 5 | 4 | ineq2i | ⊢ (  E   ∩  ( ∅  ×  ∅ ) )  =  (  E   ∩  ∅ ) | 
						
							| 6 |  | in0 | ⊢ (  E   ∩  ∅ )  =  ∅ | 
						
							| 7 | 5 6 | eqtri | ⊢ (  E   ∩  ( ∅  ×  ∅ ) )  =  ∅ | 
						
							| 8 | 7 | oveq2i | ⊢ ( ∅  Sat  (  E   ∩  ( ∅  ×  ∅ ) ) )  =  ( ∅  Sat  ∅ ) | 
						
							| 9 | 8 | fveq1i | ⊢ ( ( ∅  Sat  (  E   ∩  ( ∅  ×  ∅ ) ) ) ‘ ω )  =  ( ( ∅  Sat  ∅ ) ‘ ω ) | 
						
							| 10 | 9 | fveq1i | ⊢ ( ( ( ∅  Sat  (  E   ∩  ( ∅  ×  ∅ ) ) ) ‘ ω ) ‘ 𝑈 )  =  ( ( ( ∅  Sat  ∅ ) ‘ ω ) ‘ 𝑈 ) | 
						
							| 11 | 3 10 | eqtrdi | ⊢ ( 𝑈  ∈  𝑉  →  ( ∅  Sat∈  𝑈 )  =  ( ( ( ∅  Sat  ∅ ) ‘ ω ) ‘ 𝑈 ) ) |