| Step | Hyp | Ref | Expression | 
						
							| 1 |  | imasf1obl.u | ⊢ ( 𝜑  →  𝑈  =  ( 𝐹  “s  𝑅 ) ) | 
						
							| 2 |  | imasf1obl.v | ⊢ ( 𝜑  →  𝑉  =  ( Base ‘ 𝑅 ) ) | 
						
							| 3 |  | imasf1obl.f | ⊢ ( 𝜑  →  𝐹 : 𝑉 –1-1-onto→ 𝐵 ) | 
						
							| 4 |  | imasf1obl.r | ⊢ ( 𝜑  →  𝑅  ∈  𝑍 ) | 
						
							| 5 |  | imasf1obl.e | ⊢ 𝐸  =  ( ( dist ‘ 𝑅 )  ↾  ( 𝑉  ×  𝑉 ) ) | 
						
							| 6 |  | imasf1obl.d | ⊢ 𝐷  =  ( dist ‘ 𝑈 ) | 
						
							| 7 |  | imasf1obl.m | ⊢ ( 𝜑  →  𝐸  ∈  ( ∞Met ‘ 𝑉 ) ) | 
						
							| 8 |  | imasf1obl.x | ⊢ ( 𝜑  →  𝑃  ∈  𝑉 ) | 
						
							| 9 |  | imasf1obl.s | ⊢ ( 𝜑  →  𝑆  ∈  ℝ* ) | 
						
							| 10 |  | f1ocnvfv2 | ⊢ ( ( 𝐹 : 𝑉 –1-1-onto→ 𝐵  ∧  𝑥  ∈  𝐵 )  →  ( 𝐹 ‘ ( ◡ 𝐹 ‘ 𝑥 ) )  =  𝑥 ) | 
						
							| 11 | 3 10 | sylan | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( 𝐹 ‘ ( ◡ 𝐹 ‘ 𝑥 ) )  =  𝑥 ) | 
						
							| 12 | 11 | oveq2d | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( ( 𝐹 ‘ 𝑃 ) 𝐷 ( 𝐹 ‘ ( ◡ 𝐹 ‘ 𝑥 ) ) )  =  ( ( 𝐹 ‘ 𝑃 ) 𝐷 𝑥 ) ) | 
						
							| 13 | 1 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  𝑈  =  ( 𝐹  “s  𝑅 ) ) | 
						
							| 14 | 2 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  𝑉  =  ( Base ‘ 𝑅 ) ) | 
						
							| 15 | 3 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  𝐹 : 𝑉 –1-1-onto→ 𝐵 ) | 
						
							| 16 | 4 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  𝑅  ∈  𝑍 ) | 
						
							| 17 | 7 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  𝐸  ∈  ( ∞Met ‘ 𝑉 ) ) | 
						
							| 18 | 8 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  𝑃  ∈  𝑉 ) | 
						
							| 19 |  | f1ocnv | ⊢ ( 𝐹 : 𝑉 –1-1-onto→ 𝐵  →  ◡ 𝐹 : 𝐵 –1-1-onto→ 𝑉 ) | 
						
							| 20 | 3 19 | syl | ⊢ ( 𝜑  →  ◡ 𝐹 : 𝐵 –1-1-onto→ 𝑉 ) | 
						
							| 21 |  | f1of | ⊢ ( ◡ 𝐹 : 𝐵 –1-1-onto→ 𝑉  →  ◡ 𝐹 : 𝐵 ⟶ 𝑉 ) | 
						
							| 22 | 20 21 | syl | ⊢ ( 𝜑  →  ◡ 𝐹 : 𝐵 ⟶ 𝑉 ) | 
						
							| 23 | 22 | ffvelcdmda | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( ◡ 𝐹 ‘ 𝑥 )  ∈  𝑉 ) | 
						
							| 24 | 13 14 15 16 5 6 17 18 23 | imasdsf1o | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( ( 𝐹 ‘ 𝑃 ) 𝐷 ( 𝐹 ‘ ( ◡ 𝐹 ‘ 𝑥 ) ) )  =  ( 𝑃 𝐸 ( ◡ 𝐹 ‘ 𝑥 ) ) ) | 
						
							| 25 | 12 24 | eqtr3d | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( ( 𝐹 ‘ 𝑃 ) 𝐷 𝑥 )  =  ( 𝑃 𝐸 ( ◡ 𝐹 ‘ 𝑥 ) ) ) | 
						
							| 26 | 25 | breq1d | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( ( ( 𝐹 ‘ 𝑃 ) 𝐷 𝑥 )  <  𝑆  ↔  ( 𝑃 𝐸 ( ◡ 𝐹 ‘ 𝑥 ) )  <  𝑆 ) ) | 
						
							| 27 | 9 | adantr | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  𝑆  ∈  ℝ* ) | 
						
							| 28 |  | elbl2 | ⊢ ( ( ( 𝐸  ∈  ( ∞Met ‘ 𝑉 )  ∧  𝑆  ∈  ℝ* )  ∧  ( 𝑃  ∈  𝑉  ∧  ( ◡ 𝐹 ‘ 𝑥 )  ∈  𝑉 ) )  →  ( ( ◡ 𝐹 ‘ 𝑥 )  ∈  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 )  ↔  ( 𝑃 𝐸 ( ◡ 𝐹 ‘ 𝑥 ) )  <  𝑆 ) ) | 
						
							| 29 | 17 27 18 23 28 | syl22anc | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( ( ◡ 𝐹 ‘ 𝑥 )  ∈  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 )  ↔  ( 𝑃 𝐸 ( ◡ 𝐹 ‘ 𝑥 ) )  <  𝑆 ) ) | 
						
							| 30 | 26 29 | bitr4d | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝐵 )  →  ( ( ( 𝐹 ‘ 𝑃 ) 𝐷 𝑥 )  <  𝑆  ↔  ( ◡ 𝐹 ‘ 𝑥 )  ∈  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) ) | 
						
							| 31 | 30 | pm5.32da | ⊢ ( 𝜑  →  ( ( 𝑥  ∈  𝐵  ∧  ( ( 𝐹 ‘ 𝑃 ) 𝐷 𝑥 )  <  𝑆 )  ↔  ( 𝑥  ∈  𝐵  ∧  ( ◡ 𝐹 ‘ 𝑥 )  ∈  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) ) ) | 
						
							| 32 | 1 2 3 4 5 6 7 | imasf1oxmet | ⊢ ( 𝜑  →  𝐷  ∈  ( ∞Met ‘ 𝐵 ) ) | 
						
							| 33 |  | f1of | ⊢ ( 𝐹 : 𝑉 –1-1-onto→ 𝐵  →  𝐹 : 𝑉 ⟶ 𝐵 ) | 
						
							| 34 | 3 33 | syl | ⊢ ( 𝜑  →  𝐹 : 𝑉 ⟶ 𝐵 ) | 
						
							| 35 | 34 8 | ffvelcdmd | ⊢ ( 𝜑  →  ( 𝐹 ‘ 𝑃 )  ∈  𝐵 ) | 
						
							| 36 |  | elbl | ⊢ ( ( 𝐷  ∈  ( ∞Met ‘ 𝐵 )  ∧  ( 𝐹 ‘ 𝑃 )  ∈  𝐵  ∧  𝑆  ∈  ℝ* )  →  ( 𝑥  ∈  ( ( 𝐹 ‘ 𝑃 ) ( ball ‘ 𝐷 ) 𝑆 )  ↔  ( 𝑥  ∈  𝐵  ∧  ( ( 𝐹 ‘ 𝑃 ) 𝐷 𝑥 )  <  𝑆 ) ) ) | 
						
							| 37 | 32 35 9 36 | syl3anc | ⊢ ( 𝜑  →  ( 𝑥  ∈  ( ( 𝐹 ‘ 𝑃 ) ( ball ‘ 𝐷 ) 𝑆 )  ↔  ( 𝑥  ∈  𝐵  ∧  ( ( 𝐹 ‘ 𝑃 ) 𝐷 𝑥 )  <  𝑆 ) ) ) | 
						
							| 38 |  | f1ofn | ⊢ ( ◡ 𝐹 : 𝐵 –1-1-onto→ 𝑉  →  ◡ 𝐹  Fn  𝐵 ) | 
						
							| 39 |  | elpreima | ⊢ ( ◡ 𝐹  Fn  𝐵  →  ( 𝑥  ∈  ( ◡ ◡ 𝐹  “  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) )  ↔  ( 𝑥  ∈  𝐵  ∧  ( ◡ 𝐹 ‘ 𝑥 )  ∈  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) ) ) | 
						
							| 40 | 20 38 39 | 3syl | ⊢ ( 𝜑  →  ( 𝑥  ∈  ( ◡ ◡ 𝐹  “  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) )  ↔  ( 𝑥  ∈  𝐵  ∧  ( ◡ 𝐹 ‘ 𝑥 )  ∈  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) ) ) | 
						
							| 41 | 31 37 40 | 3bitr4d | ⊢ ( 𝜑  →  ( 𝑥  ∈  ( ( 𝐹 ‘ 𝑃 ) ( ball ‘ 𝐷 ) 𝑆 )  ↔  𝑥  ∈  ( ◡ ◡ 𝐹  “  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) ) ) | 
						
							| 42 | 41 | eqrdv | ⊢ ( 𝜑  →  ( ( 𝐹 ‘ 𝑃 ) ( ball ‘ 𝐷 ) 𝑆 )  =  ( ◡ ◡ 𝐹  “  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) ) | 
						
							| 43 |  | imacnvcnv | ⊢ ( ◡ ◡ 𝐹  “  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) )  =  ( 𝐹  “  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) | 
						
							| 44 | 42 43 | eqtrdi | ⊢ ( 𝜑  →  ( ( 𝐹 ‘ 𝑃 ) ( ball ‘ 𝐷 ) 𝑆 )  =  ( 𝐹  “  ( 𝑃 ( ball ‘ 𝐸 ) 𝑆 ) ) ) |