HSE Home Hilbert Space Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  HSE Home  >  Th. List  >  norm-ii-i Structured version   Visualization version   GIF version

Theorem norm-ii-i 28914
Description: Triangle inequality for norms. Theorem 3.3(ii) of [Beran] p. 97. (Contributed by NM, 11-Aug-1999.) (New usage is discouraged.)
Hypotheses
Ref Expression
norm-ii.1 𝐴 ∈ ℋ
norm-ii.2 𝐵 ∈ ℋ
Assertion
Ref Expression
norm-ii-i (norm‘(𝐴 + 𝐵)) ≤ ((norm𝐴) + (norm𝐵))

Proof of Theorem norm-ii-i
StepHypRef Expression
1 1re 10641 . . . . . . . . . . 11 1 ∈ ℝ
2 ax-1cn 10595 . . . . . . . . . . . 12 1 ∈ ℂ
32cjrebi 14533 . . . . . . . . . . 11 (1 ∈ ℝ ↔ (∗‘1) = 1)
41, 3mpbi 232 . . . . . . . . . 10 (∗‘1) = 1
54oveq1i 7166 . . . . . . . . 9 ((∗‘1) · (𝐵 ·ih 𝐴)) = (1 · (𝐵 ·ih 𝐴))
6 norm-ii.2 . . . . . . . . . . 11 𝐵 ∈ ℋ
7 norm-ii.1 . . . . . . . . . . 11 𝐴 ∈ ℋ
86, 7hicli 28858 . . . . . . . . . 10 (𝐵 ·ih 𝐴) ∈ ℂ
98mulid2i 10646 . . . . . . . . 9 (1 · (𝐵 ·ih 𝐴)) = (𝐵 ·ih 𝐴)
105, 9eqtri 2844 . . . . . . . 8 ((∗‘1) · (𝐵 ·ih 𝐴)) = (𝐵 ·ih 𝐴)
117, 6hicli 28858 . . . . . . . . 9 (𝐴 ·ih 𝐵) ∈ ℂ
1211mulid2i 10646 . . . . . . . 8 (1 · (𝐴 ·ih 𝐵)) = (𝐴 ·ih 𝐵)
1310, 12oveq12i 7168 . . . . . . 7 (((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) = ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵))
14 abs1 14657 . . . . . . . 8 (abs‘1) = 1
152, 6, 7, 14normlem7 28893 . . . . . . 7 (((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) ≤ (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))))
1613, 15eqbrtrri 5089 . . . . . 6 ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵)) ≤ (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))))
17 eqid 2821 . . . . . . . . . 10 -(((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) = -(((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵)))
182, 6, 7, 17normlem2 28888 . . . . . . . . 9 -(((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) ∈ ℝ
192cjcli 14528 . . . . . . . . . . . 12 (∗‘1) ∈ ℂ
2019, 8mulcli 10648 . . . . . . . . . . 11 ((∗‘1) · (𝐵 ·ih 𝐴)) ∈ ℂ
212, 11mulcli 10648 . . . . . . . . . . 11 (1 · (𝐴 ·ih 𝐵)) ∈ ℂ
2220, 21addcli 10647 . . . . . . . . . 10 (((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) ∈ ℂ
2322negrebi 10960 . . . . . . . . 9 (-(((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) ∈ ℝ ↔ (((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) ∈ ℝ)
2418, 23mpbi 232 . . . . . . . 8 (((∗‘1) · (𝐵 ·ih 𝐴)) + (1 · (𝐴 ·ih 𝐵))) ∈ ℝ
2513, 24eqeltrri 2910 . . . . . . 7 ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵)) ∈ ℝ
26 2re 11712 . . . . . . . 8 2 ∈ ℝ
27 hiidge0 28875 . . . . . . . . . . 11 (𝐴 ∈ ℋ → 0 ≤ (𝐴 ·ih 𝐴))
287, 27ax-mp 5 . . . . . . . . . 10 0 ≤ (𝐴 ·ih 𝐴)
29 hiidrcl 28872 . . . . . . . . . . . 12 (𝐴 ∈ ℋ → (𝐴 ·ih 𝐴) ∈ ℝ)
307, 29ax-mp 5 . . . . . . . . . . 11 (𝐴 ·ih 𝐴) ∈ ℝ
3130sqrtcli 14731 . . . . . . . . . 10 (0 ≤ (𝐴 ·ih 𝐴) → (√‘(𝐴 ·ih 𝐴)) ∈ ℝ)
3228, 31ax-mp 5 . . . . . . . . 9 (√‘(𝐴 ·ih 𝐴)) ∈ ℝ
33 hiidge0 28875 . . . . . . . . . . 11 (𝐵 ∈ ℋ → 0 ≤ (𝐵 ·ih 𝐵))
346, 33ax-mp 5 . . . . . . . . . 10 0 ≤ (𝐵 ·ih 𝐵)
35 hiidrcl 28872 . . . . . . . . . . . 12 (𝐵 ∈ ℋ → (𝐵 ·ih 𝐵) ∈ ℝ)
366, 35ax-mp 5 . . . . . . . . . . 11 (𝐵 ·ih 𝐵) ∈ ℝ
3736sqrtcli 14731 . . . . . . . . . 10 (0 ≤ (𝐵 ·ih 𝐵) → (√‘(𝐵 ·ih 𝐵)) ∈ ℝ)
3834, 37ax-mp 5 . . . . . . . . 9 (√‘(𝐵 ·ih 𝐵)) ∈ ℝ
3932, 38remulcli 10657 . . . . . . . 8 ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))) ∈ ℝ
4026, 39remulcli 10657 . . . . . . 7 (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵)))) ∈ ℝ
4130, 36readdcli 10656 . . . . . . 7 ((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) ∈ ℝ
4225, 40, 41leadd2i 11196 . . . . . 6 (((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵)) ≤ (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵)))) ↔ (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵))) ≤ (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))))))
4316, 42mpbi 232 . . . . 5 (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵))) ≤ (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵)))))
447, 6, 7, 6normlem8 28894 . . . . . 6 ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) = (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + ((𝐴 ·ih 𝐵) + (𝐵 ·ih 𝐴)))
4511, 8addcomi 10831 . . . . . . 7 ((𝐴 ·ih 𝐵) + (𝐵 ·ih 𝐴)) = ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵))
4645oveq2i 7167 . . . . . 6 (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + ((𝐴 ·ih 𝐵) + (𝐵 ·ih 𝐴))) = (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵)))
4744, 46eqtri 2844 . . . . 5 ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) = (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + ((𝐵 ·ih 𝐴) + (𝐴 ·ih 𝐵)))
4832recni 10655 . . . . . . 7 (√‘(𝐴 ·ih 𝐴)) ∈ ℂ
4938recni 10655 . . . . . . 7 (√‘(𝐵 ·ih 𝐵)) ∈ ℂ
5048, 49binom2i 13575 . . . . . 6 (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2) = ((((√‘(𝐴 ·ih 𝐴))↑2) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))))) + ((√‘(𝐵 ·ih 𝐵))↑2))
5148sqcli 13545 . . . . . . 7 ((√‘(𝐴 ·ih 𝐴))↑2) ∈ ℂ
52 2cn 11713 . . . . . . . 8 2 ∈ ℂ
5348, 49mulcli 10648 . . . . . . . 8 ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))) ∈ ℂ
5452, 53mulcli 10648 . . . . . . 7 (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵)))) ∈ ℂ
5549sqcli 13545 . . . . . . 7 ((√‘(𝐵 ·ih 𝐵))↑2) ∈ ℂ
5651, 54, 55add32i 10863 . . . . . 6 ((((√‘(𝐴 ·ih 𝐴))↑2) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))))) + ((√‘(𝐵 ·ih 𝐵))↑2)) = ((((√‘(𝐴 ·ih 𝐴))↑2) + ((√‘(𝐵 ·ih 𝐵))↑2)) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵)))))
5730sqsqrti 14735 . . . . . . . . 9 (0 ≤ (𝐴 ·ih 𝐴) → ((√‘(𝐴 ·ih 𝐴))↑2) = (𝐴 ·ih 𝐴))
5828, 57ax-mp 5 . . . . . . . 8 ((√‘(𝐴 ·ih 𝐴))↑2) = (𝐴 ·ih 𝐴)
5936sqsqrti 14735 . . . . . . . . 9 (0 ≤ (𝐵 ·ih 𝐵) → ((√‘(𝐵 ·ih 𝐵))↑2) = (𝐵 ·ih 𝐵))
6034, 59ax-mp 5 . . . . . . . 8 ((√‘(𝐵 ·ih 𝐵))↑2) = (𝐵 ·ih 𝐵)
6158, 60oveq12i 7168 . . . . . . 7 (((√‘(𝐴 ·ih 𝐴))↑2) + ((√‘(𝐵 ·ih 𝐵))↑2)) = ((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵))
6261oveq1i 7166 . . . . . 6 ((((√‘(𝐴 ·ih 𝐴))↑2) + ((√‘(𝐵 ·ih 𝐵))↑2)) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵))))) = (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵)))))
6350, 56, 623eqtri 2848 . . . . 5 (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2) = (((𝐴 ·ih 𝐴) + (𝐵 ·ih 𝐵)) + (2 · ((√‘(𝐴 ·ih 𝐴)) · (√‘(𝐵 ·ih 𝐵)))))
6443, 47, 633brtr4i 5096 . . . 4 ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) ≤ (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2)
657, 6hvaddcli 28795 . . . . . 6 (𝐴 + 𝐵) ∈ ℋ
66 hiidge0 28875 . . . . . 6 ((𝐴 + 𝐵) ∈ ℋ → 0 ≤ ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)))
6765, 66ax-mp 5 . . . . 5 0 ≤ ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵))
6832, 38readdcli 10656 . . . . . 6 ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵))) ∈ ℝ
6968sqge0i 13552 . . . . 5 0 ≤ (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2)
70 hiidrcl 28872 . . . . . . 7 ((𝐴 + 𝐵) ∈ ℋ → ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) ∈ ℝ)
7165, 70ax-mp 5 . . . . . 6 ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) ∈ ℝ
7268resqcli 13550 . . . . . 6 (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2) ∈ ℝ
7371, 72sqrtlei 14748 . . . . 5 ((0 ≤ ((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) ∧ 0 ≤ (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2)) → (((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) ≤ (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2) ↔ (√‘((𝐴 + 𝐵) ·ih (𝐴 + 𝐵))) ≤ (√‘(((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2))))
7467, 69, 73mp2an 690 . . . 4 (((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)) ≤ (((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2) ↔ (√‘((𝐴 + 𝐵) ·ih (𝐴 + 𝐵))) ≤ (√‘(((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2)))
7564, 74mpbi 232 . . 3 (√‘((𝐴 + 𝐵) ·ih (𝐴 + 𝐵))) ≤ (√‘(((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2))
7630sqrtge0i 14736 . . . . . 6 (0 ≤ (𝐴 ·ih 𝐴) → 0 ≤ (√‘(𝐴 ·ih 𝐴)))
7728, 76ax-mp 5 . . . . 5 0 ≤ (√‘(𝐴 ·ih 𝐴))
7836sqrtge0i 14736 . . . . . 6 (0 ≤ (𝐵 ·ih 𝐵) → 0 ≤ (√‘(𝐵 ·ih 𝐵)))
7934, 78ax-mp 5 . . . . 5 0 ≤ (√‘(𝐵 ·ih 𝐵))
8032, 38addge0i 11180 . . . . 5 ((0 ≤ (√‘(𝐴 ·ih 𝐴)) ∧ 0 ≤ (√‘(𝐵 ·ih 𝐵))) → 0 ≤ ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵))))
8177, 79, 80mp2an 690 . . . 4 0 ≤ ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))
8268sqrtsqi 14734 . . . 4 (0 ≤ ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵))) → (√‘(((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2)) = ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵))))
8381, 82ax-mp 5 . . 3 (√‘(((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))↑2)) = ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))
8475, 83breqtri 5091 . 2 (√‘((𝐴 + 𝐵) ·ih (𝐴 + 𝐵))) ≤ ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))
85 normval 28901 . . 3 ((𝐴 + 𝐵) ∈ ℋ → (norm‘(𝐴 + 𝐵)) = (√‘((𝐴 + 𝐵) ·ih (𝐴 + 𝐵))))
8665, 85ax-mp 5 . 2 (norm‘(𝐴 + 𝐵)) = (√‘((𝐴 + 𝐵) ·ih (𝐴 + 𝐵)))
87 normval 28901 . . . 4 (𝐴 ∈ ℋ → (norm𝐴) = (√‘(𝐴 ·ih 𝐴)))
887, 87ax-mp 5 . . 3 (norm𝐴) = (√‘(𝐴 ·ih 𝐴))
89 normval 28901 . . . 4 (𝐵 ∈ ℋ → (norm𝐵) = (√‘(𝐵 ·ih 𝐵)))
906, 89ax-mp 5 . . 3 (norm𝐵) = (√‘(𝐵 ·ih 𝐵))
9188, 90oveq12i 7168 . 2 ((norm𝐴) + (norm𝐵)) = ((√‘(𝐴 ·ih 𝐴)) + (√‘(𝐵 ·ih 𝐵)))
9284, 86, 913brtr4i 5096 1 (norm‘(𝐴 + 𝐵)) ≤ ((norm𝐴) + (norm𝐵))
Colors of variables: wff setvar class
Syntax hints:  wb 208   = wceq 1537  wcel 2114   class class class wbr 5066  cfv 6355  (class class class)co 7156  cr 10536  0cc0 10537  1c1 10538   + caddc 10540   · cmul 10542  cle 10676  -cneg 10871  2c2 11693  cexp 13430  ccj 14455  csqrt 14592  chba 28696   + cva 28697   ·ih csp 28699  normcno 28700
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1796  ax-4 1810  ax-5 1911  ax-6 1970  ax-7 2015  ax-8 2116  ax-9 2124  ax-10 2145  ax-11 2161  ax-12 2177  ax-ext 2793  ax-sep 5203  ax-nul 5210  ax-pow 5266  ax-pr 5330  ax-un 7461  ax-cnex 10593  ax-resscn 10594  ax-1cn 10595  ax-icn 10596  ax-addcl 10597  ax-addrcl 10598  ax-mulcl 10599  ax-mulrcl 10600  ax-mulcom 10601  ax-addass 10602  ax-mulass 10603  ax-distr 10604  ax-i2m1 10605  ax-1ne0 10606  ax-1rid 10607  ax-rnegex 10608  ax-rrecex 10609  ax-cnre 10610  ax-pre-lttri 10611  ax-pre-lttrn 10612  ax-pre-ltadd 10613  ax-pre-mulgt0 10614  ax-pre-sup 10615  ax-hfvadd 28777  ax-hv0cl 28780  ax-hfvmul 28782  ax-hvmulass 28784  ax-hvmul0 28787  ax-hfi 28856  ax-his1 28859  ax-his2 28860  ax-his3 28861  ax-his4 28862
This theorem depends on definitions:  df-bi 209  df-an 399  df-or 844  df-3or 1084  df-3an 1085  df-tru 1540  df-ex 1781  df-nf 1785  df-sb 2070  df-mo 2622  df-eu 2654  df-clab 2800  df-cleq 2814  df-clel 2893  df-nfc 2963  df-ne 3017  df-nel 3124  df-ral 3143  df-rex 3144  df-reu 3145  df-rmo 3146  df-rab 3147  df-v 3496  df-sbc 3773  df-csb 3884  df-dif 3939  df-un 3941  df-in 3943  df-ss 3952  df-pss 3954  df-nul 4292  df-if 4468  df-pw 4541  df-sn 4568  df-pr 4570  df-tp 4572  df-op 4574  df-uni 4839  df-iun 4921  df-br 5067  df-opab 5129  df-mpt 5147  df-tr 5173  df-id 5460  df-eprel 5465  df-po 5474  df-so 5475  df-fr 5514  df-we 5516  df-xp 5561  df-rel 5562  df-cnv 5563  df-co 5564  df-dm 5565  df-rn 5566  df-res 5567  df-ima 5568  df-pred 6148  df-ord 6194  df-on 6195  df-lim 6196  df-suc 6197  df-iota 6314  df-fun 6357  df-fn 6358  df-f 6359  df-f1 6360  df-fo 6361  df-f1o 6362  df-fv 6363  df-riota 7114  df-ov 7159  df-oprab 7160  df-mpo 7161  df-om 7581  df-2nd 7690  df-wrecs 7947  df-recs 8008  df-rdg 8046  df-er 8289  df-en 8510  df-dom 8511  df-sdom 8512  df-sup 8906  df-pnf 10677  df-mnf 10678  df-xr 10679  df-ltxr 10680  df-le 10681  df-sub 10872  df-neg 10873  df-div 11298  df-nn 11639  df-2 11701  df-3 11702  df-4 11703  df-n0 11899  df-z 11983  df-uz 12245  df-rp 12391  df-seq 13371  df-exp 13431  df-cj 14458  df-re 14459  df-im 14460  df-sqrt 14594  df-abs 14595  df-hnorm 28745  df-hvsub 28748
This theorem is referenced by:  norm-ii  28915  norm3difi  28924
  Copyright terms: Public domain W3C validator