| Step | Hyp | Ref | Expression | 
						
							| 1 |  | nrmmetd.x | ⊢ 𝑋  =  ( Base ‘ 𝐺 ) | 
						
							| 2 |  | nrmmetd.m | ⊢  −   =  ( -g ‘ 𝐺 ) | 
						
							| 3 |  | nrmmetd.z | ⊢  0   =  ( 0g ‘ 𝐺 ) | 
						
							| 4 |  | nrmmetd.g | ⊢ ( 𝜑  →  𝐺  ∈  Grp ) | 
						
							| 5 |  | nrmmetd.f | ⊢ ( 𝜑  →  𝐹 : 𝑋 ⟶ ℝ ) | 
						
							| 6 |  | nrmmetd.1 | ⊢ ( ( 𝜑  ∧  𝑥  ∈  𝑋 )  →  ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  ) ) | 
						
							| 7 |  | nrmmetd.2 | ⊢ ( ( 𝜑  ∧  ( 𝑥  ∈  𝑋  ∧  𝑦  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 8 | 1 2 | grpsubf | ⊢ ( 𝐺  ∈  Grp  →   −  : ( 𝑋  ×  𝑋 ) ⟶ 𝑋 ) | 
						
							| 9 | 4 8 | syl | ⊢ ( 𝜑  →   −  : ( 𝑋  ×  𝑋 ) ⟶ 𝑋 ) | 
						
							| 10 |  | fco | ⊢ ( ( 𝐹 : 𝑋 ⟶ ℝ  ∧   −  : ( 𝑋  ×  𝑋 ) ⟶ 𝑋 )  →  ( 𝐹  ∘   −  ) : ( 𝑋  ×  𝑋 ) ⟶ ℝ ) | 
						
							| 11 | 5 9 10 | syl2anc | ⊢ ( 𝜑  →  ( 𝐹  ∘   −  ) : ( 𝑋  ×  𝑋 ) ⟶ ℝ ) | 
						
							| 12 |  | opelxpi | ⊢ ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  →  〈 𝑎 ,  𝑏 〉  ∈  ( 𝑋  ×  𝑋 ) ) | 
						
							| 13 |  | fvco3 | ⊢ ( (  −  : ( 𝑋  ×  𝑋 ) ⟶ 𝑋  ∧  〈 𝑎 ,  𝑏 〉  ∈  ( 𝑋  ×  𝑋 ) )  →  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑎 ,  𝑏 〉 )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑎 ,  𝑏 〉 ) ) ) | 
						
							| 14 | 9 12 13 | syl2an | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑎 ,  𝑏 〉 )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑎 ,  𝑏 〉 ) ) ) | 
						
							| 15 |  | df-ov | ⊢ ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑎 ,  𝑏 〉 ) | 
						
							| 16 |  | df-ov | ⊢ ( 𝑎  −  𝑏 )  =  (  −  ‘ 〈 𝑎 ,  𝑏 〉 ) | 
						
							| 17 | 16 | fveq2i | ⊢ ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑎 ,  𝑏 〉 ) ) | 
						
							| 18 | 14 15 17 | 3eqtr4g | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) ) ) | 
						
							| 19 | 18 | eqeq1d | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  0  ↔  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  =  0 ) ) | 
						
							| 20 | 6 | ralrimiva | ⊢ ( 𝜑  →  ∀ 𝑥  ∈  𝑋 ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  ) ) | 
						
							| 21 | 1 2 | grpsubcl | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  →  ( 𝑎  −  𝑏 )  ∈  𝑋 ) | 
						
							| 22 | 21 | 3expb | ⊢ ( ( 𝐺  ∈  Grp  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝑎  −  𝑏 )  ∈  𝑋 ) | 
						
							| 23 | 4 22 | sylan | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝑎  −  𝑏 )  ∈  𝑋 ) | 
						
							| 24 |  | fveq2 | ⊢ ( 𝑥  =  ( 𝑎  −  𝑏 )  →  ( 𝐹 ‘ 𝑥 )  =  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) ) ) | 
						
							| 25 | 24 | eqeq1d | ⊢ ( 𝑥  =  ( 𝑎  −  𝑏 )  →  ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  =  0 ) ) | 
						
							| 26 |  | eqeq1 | ⊢ ( 𝑥  =  ( 𝑎  −  𝑏 )  →  ( 𝑥  =   0   ↔  ( 𝑎  −  𝑏 )  =   0  ) ) | 
						
							| 27 | 25 26 | bibi12d | ⊢ ( 𝑥  =  ( 𝑎  −  𝑏 )  →  ( ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  )  ↔  ( ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  =  0  ↔  ( 𝑎  −  𝑏 )  =   0  ) ) ) | 
						
							| 28 | 27 | rspccva | ⊢ ( ( ∀ 𝑥  ∈  𝑋 ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  )  ∧  ( 𝑎  −  𝑏 )  ∈  𝑋 )  →  ( ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  =  0  ↔  ( 𝑎  −  𝑏 )  =   0  ) ) | 
						
							| 29 | 20 23 28 | syl2an2r | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  =  0  ↔  ( 𝑎  −  𝑏 )  =   0  ) ) | 
						
							| 30 | 1 3 2 | grpsubeq0 | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  →  ( ( 𝑎  −  𝑏 )  =   0   ↔  𝑎  =  𝑏 ) ) | 
						
							| 31 | 30 | 3expb | ⊢ ( ( 𝐺  ∈  Grp  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝑎  −  𝑏 )  =   0   ↔  𝑎  =  𝑏 ) ) | 
						
							| 32 | 4 31 | sylan | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝑎  −  𝑏 )  =   0   ↔  𝑎  =  𝑏 ) ) | 
						
							| 33 | 19 29 32 | 3bitrd | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  0  ↔  𝑎  =  𝑏 ) ) | 
						
							| 34 | 5 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  𝐹 : 𝑋 ⟶ ℝ ) | 
						
							| 35 | 23 | adantrr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑎  −  𝑏 )  ∈  𝑋 ) | 
						
							| 36 | 34 35 | ffvelcdmd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  ∈  ℝ ) | 
						
							| 37 | 4 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  𝐺  ∈  Grp ) | 
						
							| 38 |  | simprll | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  𝑎  ∈  𝑋 ) | 
						
							| 39 |  | simprr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  𝑐  ∈  𝑋 ) | 
						
							| 40 | 1 2 | grpsubcl | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 )  →  ( 𝑎  −  𝑐 )  ∈  𝑋 ) | 
						
							| 41 | 37 38 39 40 | syl3anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑎  −  𝑐 )  ∈  𝑋 ) | 
						
							| 42 | 34 41 | ffvelcdmd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  ∈  ℝ ) | 
						
							| 43 |  | simprlr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  𝑏  ∈  𝑋 ) | 
						
							| 44 | 1 2 | grpsubcl | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑏  ∈  𝑋  ∧  𝑐  ∈  𝑋 )  →  ( 𝑏  −  𝑐 )  ∈  𝑋 ) | 
						
							| 45 | 37 43 39 44 | syl3anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑏  −  𝑐 )  ∈  𝑋 ) | 
						
							| 46 | 34 45 | ffvelcdmd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) )  ∈  ℝ ) | 
						
							| 47 | 42 46 | readdcld | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) )  ∈  ℝ ) | 
						
							| 48 | 1 2 | grpsubcl | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑐  ∈  𝑋  ∧  𝑎  ∈  𝑋 )  →  ( 𝑐  −  𝑎 )  ∈  𝑋 ) | 
						
							| 49 | 37 39 38 48 | syl3anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑐  −  𝑎 )  ∈  𝑋 ) | 
						
							| 50 | 34 49 | ffvelcdmd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  ∈  ℝ ) | 
						
							| 51 | 1 2 | grpsubcl | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑐  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  →  ( 𝑐  −  𝑏 )  ∈  𝑋 ) | 
						
							| 52 | 37 39 43 51 | syl3anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑐  −  𝑏 )  ∈  𝑋 ) | 
						
							| 53 | 34 52 | ffvelcdmd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) )  ∈  ℝ ) | 
						
							| 54 | 50 53 | readdcld | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  +  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) )  ∈  ℝ ) | 
						
							| 55 | 1 2 | grpnnncan2 | ⊢ ( ( 𝐺  ∈  Grp  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) )  =  ( 𝑎  −  𝑏 ) ) | 
						
							| 56 | 37 38 43 39 55 | syl13anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) )  =  ( 𝑎  −  𝑏 ) ) | 
						
							| 57 | 56 | fveq2d | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) ) )  =  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) ) ) | 
						
							| 58 | 7 | ralrimivva | ⊢ ( 𝜑  →  ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑋 ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 59 | 58 | adantr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑋 ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 60 |  | fvoveq1 | ⊢ ( 𝑥  =  ( 𝑎  −  𝑐 )  →  ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  =  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  𝑦 ) ) ) | 
						
							| 61 |  | fveq2 | ⊢ ( 𝑥  =  ( 𝑎  −  𝑐 )  →  ( 𝐹 ‘ 𝑥 )  =  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) ) ) | 
						
							| 62 | 61 | oveq1d | ⊢ ( 𝑥  =  ( 𝑎  −  𝑐 )  →  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) )  =  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 63 | 60 62 | breq12d | ⊢ ( 𝑥  =  ( 𝑎  −  𝑐 )  →  ( ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) )  ↔  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ 𝑦 ) ) ) ) | 
						
							| 64 |  | oveq2 | ⊢ ( 𝑦  =  ( 𝑏  −  𝑐 )  →  ( ( 𝑎  −  𝑐 )  −  𝑦 )  =  ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) ) ) | 
						
							| 65 | 64 | fveq2d | ⊢ ( 𝑦  =  ( 𝑏  −  𝑐 )  →  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  𝑦 ) )  =  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) ) ) ) | 
						
							| 66 |  | fveq2 | ⊢ ( 𝑦  =  ( 𝑏  −  𝑐 )  →  ( 𝐹 ‘ 𝑦 )  =  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) ) | 
						
							| 67 | 66 | oveq2d | ⊢ ( 𝑦  =  ( 𝑏  −  𝑐 )  →  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ 𝑦 ) )  =  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) ) ) | 
						
							| 68 | 65 67 | breq12d | ⊢ ( 𝑦  =  ( 𝑏  −  𝑐 )  →  ( ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ 𝑦 ) )  ↔  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) ) )  ≤  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) ) ) ) | 
						
							| 69 | 63 68 | rspc2va | ⊢ ( ( ( ( 𝑎  −  𝑐 )  ∈  𝑋  ∧  ( 𝑏  −  𝑐 )  ∈  𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑋 ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) ) )  →  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) ) )  ≤  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) ) ) | 
						
							| 70 | 41 45 59 69 | syl21anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( ( 𝑎  −  𝑐 )  −  ( 𝑏  −  𝑐 ) ) )  ≤  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) ) ) | 
						
							| 71 | 57 70 | eqbrtrrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  ≤  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) ) ) | 
						
							| 72 |  | eleq1w | ⊢ ( 𝑏  =  𝑐  →  ( 𝑏  ∈  𝑋  ↔  𝑐  ∈  𝑋 ) ) | 
						
							| 73 | 72 | anbi2d | ⊢ ( 𝑏  =  𝑐  →  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ↔  ( 𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) ) ) | 
						
							| 74 | 73 | anbi2d | ⊢ ( 𝑏  =  𝑐  →  ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  ↔  ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) ) ) ) | 
						
							| 75 |  | oveq2 | ⊢ ( 𝑏  =  𝑐  →  ( 𝑎  −  𝑏 )  =  ( 𝑎  −  𝑐 ) ) | 
						
							| 76 | 75 | fveq2d | ⊢ ( 𝑏  =  𝑐  →  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  =  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) ) ) | 
						
							| 77 |  | fvoveq1 | ⊢ ( 𝑏  =  𝑐  →  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) )  =  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) ) ) | 
						
							| 78 | 76 77 | breq12d | ⊢ ( 𝑏  =  𝑐  →  ( ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  ≤  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) )  ↔  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) ) ) ) | 
						
							| 79 | 74 78 | imbi12d | ⊢ ( 𝑏  =  𝑐  →  ( ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  ≤  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) )  ↔  ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) ) ) ) ) | 
						
							| 80 | 4 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  𝐺  ∈  Grp ) | 
						
							| 81 | 1 3 | grpidcl | ⊢ ( 𝐺  ∈  Grp  →   0   ∈  𝑋 ) | 
						
							| 82 | 80 81 | syl | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →   0   ∈  𝑋 ) | 
						
							| 83 |  | simprr | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  𝑏  ∈  𝑋 ) | 
						
							| 84 |  | simprl | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  𝑎  ∈  𝑋 ) | 
						
							| 85 | 1 2 | grpsubcl | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑏  ∈  𝑋  ∧  𝑎  ∈  𝑋 )  →  ( 𝑏  −  𝑎 )  ∈  𝑋 ) | 
						
							| 86 | 80 83 84 85 | syl3anc | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝑏  −  𝑎 )  ∈  𝑋 ) | 
						
							| 87 | 58 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑋 ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 88 |  | fvoveq1 | ⊢ ( 𝑥  =   0   →  ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  =  ( 𝐹 ‘ (  0   −  𝑦 ) ) ) | 
						
							| 89 |  | fveq2 | ⊢ ( 𝑥  =   0   →  ( 𝐹 ‘ 𝑥 )  =  ( 𝐹 ‘  0  ) ) | 
						
							| 90 | 89 | oveq1d | ⊢ ( 𝑥  =   0   →  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) )  =  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ 𝑦 ) ) ) | 
						
							| 91 | 88 90 | breq12d | ⊢ ( 𝑥  =   0   →  ( ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) )  ↔  ( 𝐹 ‘ (  0   −  𝑦 ) )  ≤  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ 𝑦 ) ) ) ) | 
						
							| 92 |  | oveq2 | ⊢ ( 𝑦  =  ( 𝑏  −  𝑎 )  →  (  0   −  𝑦 )  =  (  0   −  ( 𝑏  −  𝑎 ) ) ) | 
						
							| 93 | 92 | fveq2d | ⊢ ( 𝑦  =  ( 𝑏  −  𝑎 )  →  ( 𝐹 ‘ (  0   −  𝑦 ) )  =  ( 𝐹 ‘ (  0   −  ( 𝑏  −  𝑎 ) ) ) ) | 
						
							| 94 |  | fveq2 | ⊢ ( 𝑦  =  ( 𝑏  −  𝑎 )  →  ( 𝐹 ‘ 𝑦 )  =  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) | 
						
							| 95 | 94 | oveq2d | ⊢ ( 𝑦  =  ( 𝑏  −  𝑎 )  →  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ 𝑦 ) )  =  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) ) | 
						
							| 96 | 93 95 | breq12d | ⊢ ( 𝑦  =  ( 𝑏  −  𝑎 )  →  ( ( 𝐹 ‘ (  0   −  𝑦 ) )  ≤  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ 𝑦 ) )  ↔  ( 𝐹 ‘ (  0   −  ( 𝑏  −  𝑎 ) ) )  ≤  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) ) ) | 
						
							| 97 | 91 96 | rspc2va | ⊢ ( ( (  0   ∈  𝑋  ∧  ( 𝑏  −  𝑎 )  ∈  𝑋 )  ∧  ∀ 𝑥  ∈  𝑋 ∀ 𝑦  ∈  𝑋 ( 𝐹 ‘ ( 𝑥  −  𝑦 ) )  ≤  ( ( 𝐹 ‘ 𝑥 )  +  ( 𝐹 ‘ 𝑦 ) ) )  →  ( 𝐹 ‘ (  0   −  ( 𝑏  −  𝑎 ) ) )  ≤  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) ) | 
						
							| 98 | 82 86 87 97 | syl21anc | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝐹 ‘ (  0   −  ( 𝑏  −  𝑎 ) ) )  ≤  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) ) | 
						
							| 99 |  | eqid | ⊢ ( invg ‘ 𝐺 )  =  ( invg ‘ 𝐺 ) | 
						
							| 100 | 1 2 99 3 | grpinvval2 | ⊢ ( ( 𝐺  ∈  Grp  ∧  ( 𝑏  −  𝑎 )  ∈  𝑋 )  →  ( ( invg ‘ 𝐺 ) ‘ ( 𝑏  −  𝑎 ) )  =  (  0   −  ( 𝑏  −  𝑎 ) ) ) | 
						
							| 101 | 4 86 100 | syl2an2r | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( invg ‘ 𝐺 ) ‘ ( 𝑏  −  𝑎 ) )  =  (  0   −  ( 𝑏  −  𝑎 ) ) ) | 
						
							| 102 | 1 2 99 | grpinvsub | ⊢ ( ( 𝐺  ∈  Grp  ∧  𝑏  ∈  𝑋  ∧  𝑎  ∈  𝑋 )  →  ( ( invg ‘ 𝐺 ) ‘ ( 𝑏  −  𝑎 ) )  =  ( 𝑎  −  𝑏 ) ) | 
						
							| 103 | 80 83 84 102 | syl3anc | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( invg ‘ 𝐺 ) ‘ ( 𝑏  −  𝑎 ) )  =  ( 𝑎  −  𝑏 ) ) | 
						
							| 104 | 101 103 | eqtr3d | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  (  0   −  ( 𝑏  −  𝑎 ) )  =  ( 𝑎  −  𝑏 ) ) | 
						
							| 105 | 104 | fveq2d | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝐹 ‘ (  0   −  ( 𝑏  −  𝑎 ) ) )  =  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) ) ) | 
						
							| 106 | 4 81 | syl | ⊢ ( 𝜑  →   0   ∈  𝑋 ) | 
						
							| 107 |  | pm5.501 | ⊢ ( 𝑥  =   0   →  ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  ( 𝑥  =   0   ↔  ( 𝐹 ‘ 𝑥 )  =  0 ) ) ) | 
						
							| 108 |  | bicom | ⊢ ( ( 𝑥  =   0   ↔  ( 𝐹 ‘ 𝑥 )  =  0 )  ↔  ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  ) ) | 
						
							| 109 | 107 108 | bitrdi | ⊢ ( 𝑥  =   0   →  ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  ) ) ) | 
						
							| 110 | 89 | eqeq1d | ⊢ ( 𝑥  =   0   →  ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  ( 𝐹 ‘  0  )  =  0 ) ) | 
						
							| 111 | 109 110 | bitr3d | ⊢ ( 𝑥  =   0   →  ( ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  )  ↔  ( 𝐹 ‘  0  )  =  0 ) ) | 
						
							| 112 | 111 | rspccva | ⊢ ( ( ∀ 𝑥  ∈  𝑋 ( ( 𝐹 ‘ 𝑥 )  =  0  ↔  𝑥  =   0  )  ∧   0   ∈  𝑋 )  →  ( 𝐹 ‘  0  )  =  0 ) | 
						
							| 113 | 20 106 112 | syl2anc | ⊢ ( 𝜑  →  ( 𝐹 ‘  0  )  =  0 ) | 
						
							| 114 | 113 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝐹 ‘  0  )  =  0 ) | 
						
							| 115 | 114 | oveq1d | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) )  =  ( 0  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) ) | 
						
							| 116 | 5 | adantr | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  𝐹 : 𝑋 ⟶ ℝ ) | 
						
							| 117 | 116 86 | ffvelcdmd | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) )  ∈  ℝ ) | 
						
							| 118 | 117 | recnd | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) )  ∈  ℂ ) | 
						
							| 119 | 118 | addlidd | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 0  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) )  =  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) | 
						
							| 120 | 115 119 | eqtrd | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( 𝐹 ‘  0  )  +  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) )  =  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) | 
						
							| 121 | 98 105 120 | 3brtr3d | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  ≤  ( 𝐹 ‘ ( 𝑏  −  𝑎 ) ) ) | 
						
							| 122 | 79 121 | chvarvv | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) ) ) | 
						
							| 123 | 122 | adantrlr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) ) ) | 
						
							| 124 |  | eleq1w | ⊢ ( 𝑎  =  𝑏  →  ( 𝑎  ∈  𝑋  ↔  𝑏  ∈  𝑋 ) ) | 
						
							| 125 | 124 | anbi1d | ⊢ ( 𝑎  =  𝑏  →  ( ( 𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 )  ↔  ( 𝑏  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) ) ) | 
						
							| 126 | 125 | anbi2d | ⊢ ( 𝑎  =  𝑏  →  ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) )  ↔  ( 𝜑  ∧  ( 𝑏  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) ) ) ) | 
						
							| 127 |  | fvoveq1 | ⊢ ( 𝑎  =  𝑏  →  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  =  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) ) | 
						
							| 128 |  | oveq2 | ⊢ ( 𝑎  =  𝑏  →  ( 𝑐  −  𝑎 )  =  ( 𝑐  −  𝑏 ) ) | 
						
							| 129 | 128 | fveq2d | ⊢ ( 𝑎  =  𝑏  →  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  =  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) | 
						
							| 130 | 127 129 | breq12d | ⊢ ( 𝑎  =  𝑏  →  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  ↔  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) ) | 
						
							| 131 | 126 130 | imbi12d | ⊢ ( 𝑎  =  𝑏  →  ( ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) ) )  ↔  ( ( 𝜑  ∧  ( 𝑏  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) ) ) | 
						
							| 132 | 131 122 | chvarvv | ⊢ ( ( 𝜑  ∧  ( 𝑏  ∈  𝑋  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) | 
						
							| 133 | 132 | adantrll | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) )  ≤  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) | 
						
							| 134 | 42 46 50 53 123 133 | le2addd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝐹 ‘ ( 𝑎  −  𝑐 ) )  +  ( 𝐹 ‘ ( 𝑏  −  𝑐 ) ) )  ≤  ( ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  +  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) ) | 
						
							| 135 | 36 47 54 71 134 | letrd | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) )  ≤  ( ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  +  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) ) | 
						
							| 136 | 18 | adantrr | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  ( 𝐹 ‘ ( 𝑎  −  𝑏 ) ) ) | 
						
							| 137 |  | opelxpi | ⊢ ( ( 𝑐  ∈  𝑋  ∧  𝑎  ∈  𝑋 )  →  〈 𝑐 ,  𝑎 〉  ∈  ( 𝑋  ×  𝑋 ) ) | 
						
							| 138 | 39 38 137 | syl2anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  〈 𝑐 ,  𝑎 〉  ∈  ( 𝑋  ×  𝑋 ) ) | 
						
							| 139 |  | fvco3 | ⊢ ( (  −  : ( 𝑋  ×  𝑋 ) ⟶ 𝑋  ∧  〈 𝑐 ,  𝑎 〉  ∈  ( 𝑋  ×  𝑋 ) )  →  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑐 ,  𝑎 〉 )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑐 ,  𝑎 〉 ) ) ) | 
						
							| 140 | 9 138 139 | syl2an2r | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑐 ,  𝑎 〉 )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑐 ,  𝑎 〉 ) ) ) | 
						
							| 141 |  | df-ov | ⊢ ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  =  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑐 ,  𝑎 〉 ) | 
						
							| 142 |  | df-ov | ⊢ ( 𝑐  −  𝑎 )  =  (  −  ‘ 〈 𝑐 ,  𝑎 〉 ) | 
						
							| 143 | 142 | fveq2i | ⊢ ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑐 ,  𝑎 〉 ) ) | 
						
							| 144 | 140 141 143 | 3eqtr4g | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  =  ( 𝐹 ‘ ( 𝑐  −  𝑎 ) ) ) | 
						
							| 145 |  | opelxpi | ⊢ ( ( 𝑐  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  →  〈 𝑐 ,  𝑏 〉  ∈  ( 𝑋  ×  𝑋 ) ) | 
						
							| 146 | 39 43 145 | syl2anc | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  〈 𝑐 ,  𝑏 〉  ∈  ( 𝑋  ×  𝑋 ) ) | 
						
							| 147 |  | fvco3 | ⊢ ( (  −  : ( 𝑋  ×  𝑋 ) ⟶ 𝑋  ∧  〈 𝑐 ,  𝑏 〉  ∈  ( 𝑋  ×  𝑋 ) )  →  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑐 ,  𝑏 〉 )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑐 ,  𝑏 〉 ) ) ) | 
						
							| 148 | 9 146 147 | syl2an2r | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑐 ,  𝑏 〉 )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑐 ,  𝑏 〉 ) ) ) | 
						
							| 149 |  | df-ov | ⊢ ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 )  =  ( ( 𝐹  ∘   −  ) ‘ 〈 𝑐 ,  𝑏 〉 ) | 
						
							| 150 |  | df-ov | ⊢ ( 𝑐  −  𝑏 )  =  (  −  ‘ 〈 𝑐 ,  𝑏 〉 ) | 
						
							| 151 | 150 | fveq2i | ⊢ ( 𝐹 ‘ ( 𝑐  −  𝑏 ) )  =  ( 𝐹 ‘ (  −  ‘ 〈 𝑐 ,  𝑏 〉 ) ) | 
						
							| 152 | 148 149 151 | 3eqtr4g | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 )  =  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) | 
						
							| 153 | 144 152 | oveq12d | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) )  =  ( ( 𝐹 ‘ ( 𝑐  −  𝑎 ) )  +  ( 𝐹 ‘ ( 𝑐  −  𝑏 ) ) ) ) | 
						
							| 154 | 135 136 153 | 3brtr4d | ⊢ ( ( 𝜑  ∧  ( ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 )  ∧  𝑐  ∈  𝑋 ) )  →  ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  ≤  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) ) ) | 
						
							| 155 | 154 | expr | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( 𝑐  ∈  𝑋  →  ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  ≤  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) ) ) ) | 
						
							| 156 | 155 | ralrimiv | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ∀ 𝑐  ∈  𝑋 ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  ≤  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) ) ) | 
						
							| 157 | 33 156 | jca | ⊢ ( ( 𝜑  ∧  ( 𝑎  ∈  𝑋  ∧  𝑏  ∈  𝑋 ) )  →  ( ( ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  0  ↔  𝑎  =  𝑏 )  ∧  ∀ 𝑐  ∈  𝑋 ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  ≤  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) ) ) ) | 
						
							| 158 | 157 | ralrimivva | ⊢ ( 𝜑  →  ∀ 𝑎  ∈  𝑋 ∀ 𝑏  ∈  𝑋 ( ( ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  0  ↔  𝑎  =  𝑏 )  ∧  ∀ 𝑐  ∈  𝑋 ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  ≤  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) ) ) ) | 
						
							| 159 | 1 | fvexi | ⊢ 𝑋  ∈  V | 
						
							| 160 |  | ismet | ⊢ ( 𝑋  ∈  V  →  ( ( 𝐹  ∘   −  )  ∈  ( Met ‘ 𝑋 )  ↔  ( ( 𝐹  ∘   −  ) : ( 𝑋  ×  𝑋 ) ⟶ ℝ  ∧  ∀ 𝑎  ∈  𝑋 ∀ 𝑏  ∈  𝑋 ( ( ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  0  ↔  𝑎  =  𝑏 )  ∧  ∀ 𝑐  ∈  𝑋 ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  ≤  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) ) ) ) ) ) | 
						
							| 161 | 159 160 | ax-mp | ⊢ ( ( 𝐹  ∘   −  )  ∈  ( Met ‘ 𝑋 )  ↔  ( ( 𝐹  ∘   −  ) : ( 𝑋  ×  𝑋 ) ⟶ ℝ  ∧  ∀ 𝑎  ∈  𝑋 ∀ 𝑏  ∈  𝑋 ( ( ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  =  0  ↔  𝑎  =  𝑏 )  ∧  ∀ 𝑐  ∈  𝑋 ( 𝑎 ( 𝐹  ∘   −  ) 𝑏 )  ≤  ( ( 𝑐 ( 𝐹  ∘   −  ) 𝑎 )  +  ( 𝑐 ( 𝐹  ∘   −  ) 𝑏 ) ) ) ) ) | 
						
							| 162 | 11 158 161 | sylanbrc | ⊢ ( 𝜑  →  ( 𝐹  ∘   −  )  ∈  ( Met ‘ 𝑋 ) ) |