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Theorem nmbdfnlbi 31811
Description: A lower bound for the norm of a bounded linear functional. (Contributed by NM, 25-Apr-2006.) (New usage is discouraged.)
Hypothesis
Ref Expression
nmbdfnlb.1 (𝑇 ∈ LinFn ∧ (normfnβ€˜π‘‡) ∈ ℝ)
Assertion
Ref Expression
nmbdfnlbi (𝐴 ∈ β„‹ β†’ (absβ€˜(π‘‡β€˜π΄)) ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)))
Proof of Theorem nmbdfnlbi
StepHypRef Expression
1 fveq2 6885 . . . . . 6 (𝐴 = 0β„Ž β†’ (π‘‡β€˜π΄) = (π‘‡β€˜0β„Ž))
2 nmbdfnlb.1 . . . . . . . 8 (𝑇 ∈ LinFn ∧ (normfnβ€˜π‘‡) ∈ ℝ)
32simpli 483 . . . . . . 7 𝑇 ∈ LinFn
43lnfn0i 31804 . . . . . 6 (π‘‡β€˜0β„Ž) = 0
51, 4eqtrdi 2782 . . . . 5 (𝐴 = 0β„Ž β†’ (π‘‡β€˜π΄) = 0)
65abs00bd 15244 . . . 4 (𝐴 = 0β„Ž β†’ (absβ€˜(π‘‡β€˜π΄)) = 0)
7 0le0 12317 . . . . 5 0 ≀ 0
8 fveq2 6885 . . . . . . . 8 (𝐴 = 0β„Ž β†’ (normβ„Žβ€˜π΄) = (normβ„Žβ€˜0β„Ž))
9 norm0 30890 . . . . . . . 8 (normβ„Žβ€˜0β„Ž) = 0
108, 9eqtrdi 2782 . . . . . . 7 (𝐴 = 0β„Ž β†’ (normβ„Žβ€˜π΄) = 0)
1110oveq2d 7421 . . . . . 6 (𝐴 = 0β„Ž β†’ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)) = ((normfnβ€˜π‘‡) Β· 0))
122simpri 485 . . . . . . . 8 (normfnβ€˜π‘‡) ∈ ℝ
1312recni 11232 . . . . . . 7 (normfnβ€˜π‘‡) ∈ β„‚
1413mul01i 11408 . . . . . 6 ((normfnβ€˜π‘‡) Β· 0) = 0
1511, 14eqtr2di 2783 . . . . 5 (𝐴 = 0β„Ž β†’ 0 = ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)))
167, 15breqtrid 5178 . . . 4 (𝐴 = 0β„Ž β†’ 0 ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)))
176, 16eqbrtrd 5163 . . 3 (𝐴 = 0β„Ž β†’ (absβ€˜(π‘‡β€˜π΄)) ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)))
1817adantl 481 . 2 ((𝐴 ∈ β„‹ ∧ 𝐴 = 0β„Ž) β†’ (absβ€˜(π‘‡β€˜π΄)) ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)))
193lnfnfi 31803 . . . . . . . . . 10 𝑇: β„‹βŸΆβ„‚
2019ffvelcdmi 7079 . . . . . . . . 9 (𝐴 ∈ β„‹ β†’ (π‘‡β€˜π΄) ∈ β„‚)
2120abscld 15389 . . . . . . . 8 (𝐴 ∈ β„‹ β†’ (absβ€˜(π‘‡β€˜π΄)) ∈ ℝ)
2221adantr 480 . . . . . . 7 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (absβ€˜(π‘‡β€˜π΄)) ∈ ℝ)
2322recnd 11246 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (absβ€˜(π‘‡β€˜π΄)) ∈ β„‚)
24 normcl 30887 . . . . . . . 8 (𝐴 ∈ β„‹ β†’ (normβ„Žβ€˜π΄) ∈ ℝ)
2524adantr 480 . . . . . . 7 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (normβ„Žβ€˜π΄) ∈ ℝ)
2625recnd 11246 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (normβ„Žβ€˜π΄) ∈ β„‚)
27 normne0 30892 . . . . . . 7 (𝐴 ∈ β„‹ β†’ ((normβ„Žβ€˜π΄) β‰  0 ↔ 𝐴 β‰  0β„Ž))
2827biimpar 477 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (normβ„Žβ€˜π΄) β‰  0)
2923, 26, 28divrec2d 11998 . . . . 5 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ ((absβ€˜(π‘‡β€˜π΄)) / (normβ„Žβ€˜π΄)) = ((1 / (normβ„Žβ€˜π΄)) Β· (absβ€˜(π‘‡β€˜π΄))))
3025, 28rereccld 12045 . . . . . . . . 9 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (1 / (normβ„Žβ€˜π΄)) ∈ ℝ)
3130recnd 11246 . . . . . . . 8 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (1 / (normβ„Žβ€˜π΄)) ∈ β„‚)
32 simpl 482 . . . . . . . 8 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ 𝐴 ∈ β„‹)
333lnfnmuli 31806 . . . . . . . 8 (((1 / (normβ„Žβ€˜π΄)) ∈ β„‚ ∧ 𝐴 ∈ β„‹) β†’ (π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) = ((1 / (normβ„Žβ€˜π΄)) Β· (π‘‡β€˜π΄)))
3431, 32, 33syl2anc 583 . . . . . . 7 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) = ((1 / (normβ„Žβ€˜π΄)) Β· (π‘‡β€˜π΄)))
3534fveq2d 6889 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (absβ€˜(π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴))) = (absβ€˜((1 / (normβ„Žβ€˜π΄)) Β· (π‘‡β€˜π΄))))
3620adantr 480 . . . . . . 7 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (π‘‡β€˜π΄) ∈ β„‚)
3731, 36absmuld 15407 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (absβ€˜((1 / (normβ„Žβ€˜π΄)) Β· (π‘‡β€˜π΄))) = ((absβ€˜(1 / (normβ„Žβ€˜π΄))) Β· (absβ€˜(π‘‡β€˜π΄))))
38 normgt0 30889 . . . . . . . . . . 11 (𝐴 ∈ β„‹ β†’ (𝐴 β‰  0β„Ž ↔ 0 < (normβ„Žβ€˜π΄)))
3938biimpa 476 . . . . . . . . . 10 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ 0 < (normβ„Žβ€˜π΄))
4025, 39recgt0d 12152 . . . . . . . . 9 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ 0 < (1 / (normβ„Žβ€˜π΄)))
41 0re 11220 . . . . . . . . . 10 0 ∈ ℝ
42 ltle 11306 . . . . . . . . . 10 ((0 ∈ ℝ ∧ (1 / (normβ„Žβ€˜π΄)) ∈ ℝ) β†’ (0 < (1 / (normβ„Žβ€˜π΄)) β†’ 0 ≀ (1 / (normβ„Žβ€˜π΄))))
4341, 42mpan 687 . . . . . . . . 9 ((1 / (normβ„Žβ€˜π΄)) ∈ ℝ β†’ (0 < (1 / (normβ„Žβ€˜π΄)) β†’ 0 ≀ (1 / (normβ„Žβ€˜π΄))))
4430, 40, 43sylc 65 . . . . . . . 8 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ 0 ≀ (1 / (normβ„Žβ€˜π΄)))
4530, 44absidd 15375 . . . . . . 7 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (absβ€˜(1 / (normβ„Žβ€˜π΄))) = (1 / (normβ„Žβ€˜π΄)))
4645oveq1d 7420 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ ((absβ€˜(1 / (normβ„Žβ€˜π΄))) Β· (absβ€˜(π‘‡β€˜π΄))) = ((1 / (normβ„Žβ€˜π΄)) Β· (absβ€˜(π‘‡β€˜π΄))))
4735, 37, 463eqtrrd 2771 . . . . 5 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ ((1 / (normβ„Žβ€˜π΄)) Β· (absβ€˜(π‘‡β€˜π΄))) = (absβ€˜(π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴))))
4829, 47eqtrd 2766 . . . 4 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ ((absβ€˜(π‘‡β€˜π΄)) / (normβ„Žβ€˜π΄)) = (absβ€˜(π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴))))
49 hvmulcl 30775 . . . . . 6 (((1 / (normβ„Žβ€˜π΄)) ∈ β„‚ ∧ 𝐴 ∈ β„‹) β†’ ((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴) ∈ β„‹)
5031, 32, 49syl2anc 583 . . . . 5 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ ((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴) ∈ β„‹)
51 normcl 30887 . . . . . . 7 (((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴) ∈ β„‹ β†’ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) ∈ ℝ)
5250, 51syl 17 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) ∈ ℝ)
53 norm1 31011 . . . . . 6 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) = 1)
54 eqle 11320 . . . . . 6 (((normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) ∈ ℝ ∧ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) = 1) β†’ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) ≀ 1)
5552, 53, 54syl2anc 583 . . . . 5 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) ≀ 1)
56 nmfnlb 31686 . . . . . 6 ((𝑇: β„‹βŸΆβ„‚ ∧ ((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴) ∈ β„‹ ∧ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) ≀ 1) β†’ (absβ€˜(π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴))) ≀ (normfnβ€˜π‘‡))
5719, 56mp3an1 1444 . . . . 5 ((((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴) ∈ β„‹ ∧ (normβ„Žβ€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴)) ≀ 1) β†’ (absβ€˜(π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴))) ≀ (normfnβ€˜π‘‡))
5850, 55, 57syl2anc 583 . . . 4 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (absβ€˜(π‘‡β€˜((1 / (normβ„Žβ€˜π΄)) Β·β„Ž 𝐴))) ≀ (normfnβ€˜π‘‡))
5948, 58eqbrtrd 5163 . . 3 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ ((absβ€˜(π‘‡β€˜π΄)) / (normβ„Žβ€˜π΄)) ≀ (normfnβ€˜π‘‡))
6012a1i 11 . . . 4 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (normfnβ€˜π‘‡) ∈ ℝ)
61 ledivmul2 12097 . . . 4 (((absβ€˜(π‘‡β€˜π΄)) ∈ ℝ ∧ (normfnβ€˜π‘‡) ∈ ℝ ∧ ((normβ„Žβ€˜π΄) ∈ ℝ ∧ 0 < (normβ„Žβ€˜π΄))) β†’ (((absβ€˜(π‘‡β€˜π΄)) / (normβ„Žβ€˜π΄)) ≀ (normfnβ€˜π‘‡) ↔ (absβ€˜(π‘‡β€˜π΄)) ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄))))
6222, 60, 25, 39, 61syl112anc 1371 . . 3 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (((absβ€˜(π‘‡β€˜π΄)) / (normβ„Žβ€˜π΄)) ≀ (normfnβ€˜π‘‡) ↔ (absβ€˜(π‘‡β€˜π΄)) ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄))))
6359, 62mpbid 231 . 2 ((𝐴 ∈ β„‹ ∧ 𝐴 β‰  0β„Ž) β†’ (absβ€˜(π‘‡β€˜π΄)) ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)))
6418, 63pm2.61dane 3023 1 (𝐴 ∈ β„‹ β†’ (absβ€˜(π‘‡β€˜π΄)) ≀ ((normfnβ€˜π‘‡) Β· (normβ„Žβ€˜π΄)))
Colors of variables: wff setvar class
Syntax hints:   β†’ wi 4   ↔ wb 205   ∧ wa 395   = wceq 1533   ∈ wcel 2098   β‰  wne 2934   class class class wbr 5141  βŸΆwf 6533  β€˜cfv 6537  (class class class)co 7405  β„‚cc 11110  β„cr 11111  0cc0 11112  1c1 11113   Β· cmul 11117   < clt 11252   ≀ cle 11253   / cdiv 11875  abscabs 15187   β„‹chba 30681   Β·β„Ž csm 30683  normβ„Žcno 30685  0β„Žc0v 30686  normfncnmf 30713  LinFnclf 30716
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1789  ax-4 1803  ax-5 1905  ax-6 1963  ax-7 2003  ax-8 2100  ax-9 2108  ax-10 2129  ax-11 2146  ax-12 2163  ax-ext 2697  ax-sep 5292  ax-nul 5299  ax-pow 5356  ax-pr 5420  ax-un 7722  ax-cnex 11168  ax-resscn 11169  ax-1cn 11170  ax-icn 11171  ax-addcl 11172  ax-addrcl 11173  ax-mulcl 11174  ax-mulrcl 11175  ax-mulcom 11176  ax-addass 11177  ax-mulass 11178  ax-distr 11179  ax-i2m1 11180  ax-1ne0 11181  ax-1rid 11182  ax-rnegex 11183  ax-rrecex 11184  ax-cnre 11185  ax-pre-lttri 11186  ax-pre-lttrn 11187  ax-pre-ltadd 11188  ax-pre-mulgt0 11189  ax-pre-sup 11190  ax-hilex 30761  ax-hv0cl 30765  ax-hvaddid 30766  ax-hfvmul 30767  ax-hvmulid 30768  ax-hvmul0 30772  ax-hfi 30841  ax-his1 30844  ax-his3 30846  ax-his4 30847
This theorem depends on definitions:  df-bi 206  df-an 396  df-or 845  df-3or 1085  df-3an 1086  df-tru 1536  df-fal 1546  df-ex 1774  df-nf 1778  df-sb 2060  df-mo 2528  df-eu 2557  df-clab 2704  df-cleq 2718  df-clel 2804  df-nfc 2879  df-ne 2935  df-nel 3041  df-ral 3056  df-rex 3065  df-rmo 3370  df-reu 3371  df-rab 3427  df-v 3470  df-sbc 3773  df-csb 3889  df-dif 3946  df-un 3948  df-in 3950  df-ss 3960  df-pss 3962  df-nul 4318  df-if 4524  df-pw 4599  df-sn 4624  df-pr 4626  df-op 4630  df-uni 4903  df-iun 4992  df-br 5142  df-opab 5204  df-mpt 5225  df-tr 5259  df-id 5567  df-eprel 5573  df-po 5581  df-so 5582  df-fr 5624  df-we 5626  df-xp 5675  df-rel 5676  df-cnv 5677  df-co 5678  df-dm 5679  df-rn 5680  df-res 5681  df-ima 5682  df-pred 6294  df-ord 6361  df-on 6362  df-lim 6363  df-suc 6364  df-iota 6489  df-fun 6539  df-fn 6540  df-f 6541  df-f1 6542  df-fo 6543  df-f1o 6544  df-fv 6545  df-riota 7361  df-ov 7408  df-oprab 7409  df-mpo 7410  df-om 7853  df-2nd 7975  df-frecs 8267  df-wrecs 8298  df-recs 8372  df-rdg 8411  df-er 8705  df-map 8824  df-en 8942  df-dom 8943  df-sdom 8944  df-sup 9439  df-pnf 11254  df-mnf 11255  df-xr 11256  df-ltxr 11257  df-le 11258  df-sub 11450  df-neg 11451  df-div 11876  df-nn 12217  df-2 12279  df-3 12280  df-n0 12477  df-z 12563  df-uz 12827  df-rp 12981  df-seq 13973  df-exp 14033  df-cj 15052  df-re 15053  df-im 15054  df-sqrt 15188  df-abs 15189  df-hnorm 30730  df-nmfn 31607  df-lnfn 31610
This theorem is referenced by:  nmbdfnlb  31812
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