Theorem isxmet2d 24367

Description: It is safe to only require the triangle inequality when the values are real (so that we can use the standard addition over the reals), but in this case the nonnegativity constraint cannot be deduced and must be provided separately. (Counterexample: 𝐷(𝑥, 𝑦) = if(𝑥 = 𝑦, 0, -∞) satisfies all hypotheses except nonnegativity.) (Contributed by Mario Carneiro, 20-Aug-2015.)

Hypotheses

Ref	Expression
isxmetd.0	⊢ (𝜑 → 𝑋 ∈ 𝑉)
isxmetd.1	⊢ (𝜑 → 𝐷:(𝑋 × 𝑋)⟶ℝ*)
isxmet2d.2	⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → 0 ≤ (𝑥𝐷𝑦))
isxmet2d.3	⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥𝐷𝑦) ≤ 0 ↔ 𝑥 = 𝑦))
isxmet2d.4	⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋) ∧ ((𝑧𝐷𝑥) ∈ ℝ ∧ (𝑧𝐷𝑦) ∈ ℝ)) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) + (𝑧𝐷𝑦)))

Assertion

Ref	Expression
isxmet2d	⊢ (𝜑 → 𝐷 ∈ (∞Met‘𝑋))

Distinct variable groups:   𝑥,𝑦,𝑧,𝐷   𝜑,𝑥,𝑦,𝑧   𝑥,𝑋,𝑦,𝑧

Allowed substitution hints:   𝑉(𝑥,𝑦,𝑧)

Proof of Theorem isxmet2d

Step	Hyp	Ref	Expression
1		isxmetd.0	. 2 ⊢ (𝜑 → 𝑋 ∈ 𝑉)
2		isxmetd.1	. 2 ⊢ (𝜑 → 𝐷:(𝑋 × 𝑋)⟶ℝ*)
3	2	fovcdmda 7563	. . . 4 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝑥𝐷𝑦) ∈ ℝ*)
4		0xr 11226	. . . 4 ⊢ 0 ∈ ℝ*
5		xrletri3 13153	. . . 4 ⊢ (((𝑥𝐷𝑦) ∈ ℝ* ∧ 0 ∈ ℝ*) → ((𝑥𝐷𝑦) = 0 ↔ ((𝑥𝐷𝑦) ≤ 0 ∧ 0 ≤ (𝑥𝐷𝑦))))
6	3, 4, 5	sylancl 595	. . 3 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥𝐷𝑦) = 0 ↔ ((𝑥𝐷𝑦) ≤ 0 ∧ 0 ≤ (𝑥𝐷𝑦))))
7		isxmet2d.2	. . . 4 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → 0 ≤ (𝑥𝐷𝑦))
8	7	biantrud 539	. . 3 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥𝐷𝑦) ≤ 0 ↔ ((𝑥𝐷𝑦) ≤ 0 ∧ 0 ≤ (𝑥𝐷𝑦))))
9		isxmet2d.3	. . 3 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥𝐷𝑦) ≤ 0 ↔ 𝑥 = 𝑦))
10	6, 8, 9	3bitr2d 309	. 2 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → ((𝑥𝐷𝑦) = 0 ↔ 𝑥 = 𝑦))
11		isxmet2d.4	. . . . . . 7 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋) ∧ ((𝑧𝐷𝑥) ∈ ℝ ∧ (𝑧𝐷𝑦) ∈ ℝ)) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) + (𝑧𝐷𝑦)))
12	11	3expa 1130	. . . . . 6 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ ((𝑧𝐷𝑥) ∈ ℝ ∧ (𝑧𝐷𝑦) ∈ ℝ)) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) + (𝑧𝐷𝑦)))
13		rexadd 13232	. . . . . . 7 ⊢ (((𝑧𝐷𝑥) ∈ ℝ ∧ (𝑧𝐷𝑦) ∈ ℝ) → ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) = ((𝑧𝐷𝑥) + (𝑧𝐷𝑦)))
14	13	adantl 485	. . . . . 6 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ ((𝑧𝐷𝑥) ∈ ℝ ∧ (𝑧𝐷𝑦) ∈ ℝ)) → ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) = ((𝑧𝐷𝑥) + (𝑧𝐷𝑦)))
15	12, 14	breqtrrd 5127	. . . . 5 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ ((𝑧𝐷𝑥) ∈ ℝ ∧ (𝑧𝐷𝑦) ∈ ℝ)) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
16	15	anassrs 471	. . . 4 ⊢ ((((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) ∧ (𝑧𝐷𝑦) ∈ ℝ) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
17	3	3adantr3 1184	. . . . . . 7 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑥𝐷𝑦) ∈ ℝ*)
18		pnfge 13129	. . . . . . 7 ⊢ ((𝑥𝐷𝑦) ∈ ℝ* → (𝑥𝐷𝑦) ≤ +∞)
19	17, 18	syl 17	. . . . . 6 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑥𝐷𝑦) ≤ +∞)
20	19	ad2antrr 736	. . . . 5 ⊢ ((((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) ∧ (𝑧𝐷𝑦) = +∞) → (𝑥𝐷𝑦) ≤ +∞)
21		oveq2 7400	. . . . . 6 ⊢ ((𝑧𝐷𝑦) = +∞ → ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) = ((𝑧𝐷𝑥) +𝑒 +∞))
22	2	ffnd 6688	. . . . . . . . . . 11 ⊢ (𝜑 → 𝐷 Fn (𝑋 × 𝑋))
23		elxrge0 13458	. . . . . . . . . . . . 13 ⊢ ((𝑥𝐷𝑦) ∈ (0[,]+∞) ↔ ((𝑥𝐷𝑦) ∈ ℝ* ∧ 0 ≤ (𝑥𝐷𝑦)))
24	3, 7, 23	sylanbrc 592	. . . . . . . . . . . 12 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋)) → (𝑥𝐷𝑦) ∈ (0[,]+∞))
25	24	ralrimivva 3204	. . . . . . . . . . 11 ⊢ (𝜑 → ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝑥𝐷𝑦) ∈ (0[,]+∞))
26		ffnov 7518	. . . . . . . . . . 11 ⊢ (𝐷:(𝑋 × 𝑋)⟶(0[,]+∞) ↔ (𝐷 Fn (𝑋 × 𝑋) ∧ ∀𝑥 ∈ 𝑋 ∀𝑦 ∈ 𝑋 (𝑥𝐷𝑦) ∈ (0[,]+∞)))
27	22, 25, 26	sylanbrc 592	. . . . . . . . . 10 ⊢ (𝜑 → 𝐷:(𝑋 × 𝑋)⟶(0[,]+∞))
28	27	adantr 484	. . . . . . . . 9 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → 𝐷:(𝑋 × 𝑋)⟶(0[,]+∞))
29		simpr3 1209	. . . . . . . . 9 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → 𝑧 ∈ 𝑋)
30		simpr1 1207	. . . . . . . . 9 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → 𝑥 ∈ 𝑋)
31	28, 29, 30	fovcdmd 7564	. . . . . . . 8 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑧𝐷𝑥) ∈ (0[,]+∞))
32		eliccxr 13436	. . . . . . . 8 ⊢ ((𝑧𝐷𝑥) ∈ (0[,]+∞) → (𝑧𝐷𝑥) ∈ ℝ*)
33	31, 32	syl 17	. . . . . . 7 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑧𝐷𝑥) ∈ ℝ*)
34		renemnf 11228	. . . . . . 7 ⊢ ((𝑧𝐷𝑥) ∈ ℝ → (𝑧𝐷𝑥) ≠ -∞)
35		xaddpnf1 13226	. . . . . . 7 ⊢ (((𝑧𝐷𝑥) ∈ ℝ* ∧ (𝑧𝐷𝑥) ≠ -∞) → ((𝑧𝐷𝑥) +𝑒 +∞) = +∞)
36	33, 34, 35	syl2an 605	. . . . . 6 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) → ((𝑧𝐷𝑥) +𝑒 +∞) = +∞)
37	21, 36	sylan9eqr 2818	. . . . 5 ⊢ ((((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) ∧ (𝑧𝐷𝑦) = +∞) → ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) = +∞)
38	20, 37	breqtrrd 5127	. . . 4 ⊢ ((((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) ∧ (𝑧𝐷𝑦) = +∞) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
39		simpr2 1208	. . . . . . . . . . 11 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → 𝑦 ∈ 𝑋)
40	28, 29, 39	fovcdmd 7564	. . . . . . . . . 10 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑧𝐷𝑦) ∈ (0[,]+∞))
41		eliccxr 13436	. . . . . . . . . 10 ⊢ ((𝑧𝐷𝑦) ∈ (0[,]+∞) → (𝑧𝐷𝑦) ∈ ℝ*)
42	40, 41	syl 17	. . . . . . . . 9 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑧𝐷𝑦) ∈ ℝ*)
43		elxrge0 13458	. . . . . . . . . . 11 ⊢ ((𝑧𝐷𝑦) ∈ (0[,]+∞) ↔ ((𝑧𝐷𝑦) ∈ ℝ* ∧ 0 ≤ (𝑧𝐷𝑦)))
44	43	simprbi 501	. . . . . . . . . 10 ⊢ ((𝑧𝐷𝑦) ∈ (0[,]+∞) → 0 ≤ (𝑧𝐷𝑦))
45	40, 44	syl 17	. . . . . . . . 9 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → 0 ≤ (𝑧𝐷𝑦))
46		ge0nemnf 13173	. . . . . . . . 9 ⊢ (((𝑧𝐷𝑦) ∈ ℝ* ∧ 0 ≤ (𝑧𝐷𝑦)) → (𝑧𝐷𝑦) ≠ -∞)
47	42, 45, 46	syl2anc 593	. . . . . . . 8 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑧𝐷𝑦) ≠ -∞)
48	47	a1d 25	. . . . . . 7 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (¬ (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) → (𝑧𝐷𝑦) ≠ -∞))
49	48	necon4bd 2976	. . . . . 6 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → ((𝑧𝐷𝑦) = -∞ → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦))))
50	49	adantr 484	. . . . 5 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) → ((𝑧𝐷𝑦) = -∞ → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦))))
51	50	imp 410	. . . 4 ⊢ ((((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) ∧ (𝑧𝐷𝑦) = -∞) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
52	42	adantr 484	. . . . 5 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) → (𝑧𝐷𝑦) ∈ ℝ*)
53		elxr 13115	. . . . 5 ⊢ ((𝑧𝐷𝑦) ∈ ℝ* ↔ ((𝑧𝐷𝑦) ∈ ℝ ∨ (𝑧𝐷𝑦) = +∞ ∨ (𝑧𝐷𝑦) = -∞))
54	52, 53	sylib 220	. . . 4 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) → ((𝑧𝐷𝑦) ∈ ℝ ∨ (𝑧𝐷𝑦) = +∞ ∨ (𝑧𝐷𝑦) = -∞))
55	16, 38, 51, 54	mpjao3dan 1451	. . 3 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) ∈ ℝ) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
56	19	adantr 484	. . . 4 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) = +∞) → (𝑥𝐷𝑦) ≤ +∞)
57		oveq1 7399	. . . . 5 ⊢ ((𝑧𝐷𝑥) = +∞ → ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) = (+∞ +𝑒 (𝑧𝐷𝑦)))
58		xaddpnf2 13227	. . . . . 6 ⊢ (((𝑧𝐷𝑦) ∈ ℝ* ∧ (𝑧𝐷𝑦) ≠ -∞) → (+∞ +𝑒 (𝑧𝐷𝑦)) = +∞)
59	42, 47, 58	syl2anc 593	. . . . 5 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (+∞ +𝑒 (𝑧𝐷𝑦)) = +∞)
60	57, 59	sylan9eqr 2818	. . . 4 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) = +∞) → ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) = +∞)
61	56, 60	breqtrrd 5127	. . 3 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) = +∞) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
62		elxrge0 13458	. . . . . . . . 9 ⊢ ((𝑧𝐷𝑥) ∈ (0[,]+∞) ↔ ((𝑧𝐷𝑥) ∈ ℝ* ∧ 0 ≤ (𝑧𝐷𝑥)))
63	62	simprbi 501	. . . . . . . 8 ⊢ ((𝑧𝐷𝑥) ∈ (0[,]+∞) → 0 ≤ (𝑧𝐷𝑥))
64	31, 63	syl 17	. . . . . . 7 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → 0 ≤ (𝑧𝐷𝑥))
65		ge0nemnf 13173	. . . . . . 7 ⊢ (((𝑧𝐷𝑥) ∈ ℝ* ∧ 0 ≤ (𝑧𝐷𝑥)) → (𝑧𝐷𝑥) ≠ -∞)
66	33, 64, 65	syl2anc 593	. . . . . 6 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑧𝐷𝑥) ≠ -∞)
67	66	a1d 25	. . . . 5 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (¬ (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)) → (𝑧𝐷𝑥) ≠ -∞))
68	67	necon4bd 2976	. . . 4 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → ((𝑧𝐷𝑥) = -∞ → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦))))
69	68	imp 410	. . 3 ⊢ (((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) ∧ (𝑧𝐷𝑥) = -∞) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
70		elxr 13115	. . . 4 ⊢ ((𝑧𝐷𝑥) ∈ ℝ* ↔ ((𝑧𝐷𝑥) ∈ ℝ ∨ (𝑧𝐷𝑥) = +∞ ∨ (𝑧𝐷𝑥) = -∞))
71	33, 70	sylib 220	. . 3 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → ((𝑧𝐷𝑥) ∈ ℝ ∨ (𝑧𝐷𝑥) = +∞ ∨ (𝑧𝐷𝑥) = -∞))
72	55, 61, 69, 71	mpjao3dan 1451	. 2 ⊢ ((𝜑 ∧ (𝑥 ∈ 𝑋 ∧ 𝑦 ∈ 𝑋 ∧ 𝑧 ∈ 𝑋)) → (𝑥𝐷𝑦) ≤ ((𝑧𝐷𝑥) +𝑒 (𝑧𝐷𝑦)))
73	1, 2, 10, 72	isxmetd 24366	1 ⊢ (𝜑 → 𝐷 ∈ (∞Met‘𝑋))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 208   ∧ wa 399   ∨ w3o 1096   ∧ w3a 1097   = wceq 1559   ∈ wcel 2141   ≠ wne 2956  ∀wral 3075   class class class wbr 5099   × cxp 5643   Fn wfn 6512  ⟶wf 6513  ‘cfv 6517  (class class class)co 7392  ℝcr 11069  0cc0 11070   + caddc 11073  +∞cpnf 11210  -∞cmnf 11211  ℝ^*cxr 11212   ≤ cle 11214   +_𝑒 cxad 13109  [,]cicc 13349  ∞Metcxmet 21389

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1814  ax-4 1828  ax-5 1929  ax-6 1986  ax-7 2027  ax-8 2143  ax-9 2151  ax-10 2174  ax-11 2190  ax-12 2211  ax-ext 2733  ax-sep 5245  ax-nul 5255  ax-pow 5321  ax-pr 5389  ax-un 7714  ax-cnex 11126  ax-resscn 11127  ax-1cn 11128  ax-icn 11129  ax-addcl 11130  ax-addrcl 11131  ax-mulcl 11132  ax-i2m1 11138  ax-rnegex 11141  ax-cnre 11143  ax-pre-lttri 11144  ax-pre-lttrn 11145

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-3or 1098  df-3an 1099  df-tru 1562  df-fal 1572  df-ex 1799  df-nf 1803  df-sb 2090  df-mo 2565  df-eu 2595  df-clab 2740  df-cleq 2753  df-clel 2836  df-nfc 2910  df-ne 2957  df-nel 3061  df-ral 3076  df-rex 3086  df-rab 3414  df-v 3455  df-sbc 3745  df-csb 3853  df-dif 3907  df-un 3909  df-in 3911  df-ss 3921  df-nul 4286  df-if 4480  df-pw 4556  df-sn 4582  df-pr 4584  df-op 4588  df-uni 4865  df-iun 4950  df-br 5100  df-opab 5162  df-mpt 5181  df-id 5540  df-po 5553  df-so 5554  df-xp 5651  df-rel 5652  df-cnv 5653  df-co 5654  df-dm 5655  df-rn 5656  df-res 5657  df-ima 5658  df-iota 6473  df-fun 6519  df-fn 6520  df-f 6521  df-f1 6522  df-fo 6523  df-f1o 6524  df-fv 6525  df-ov 7395  df-oprab 7396  df-mpo 7397  df-1st 7966  df-2nd 7967  df-er 8673  df-map 8805  df-en 8924  df-dom 8925  df-sdom 8926  df-pnf 11215  df-mnf 11216  df-xr 11217  df-ltxr 11218  df-le 11219  df-xadd 13112  df-icc 13353  df-xmet 21397

This theorem is referenced by:  prdsxmetlem  24408  xrsxmet  24850