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Theorem sspph 27094
Description: A subspace of an inner product space is an inner product space. (Contributed by NM, 1-Feb-2008.) (New usage is discouraged.)
Hypothesis
Ref Expression
sspph.h 𝐻 = (SubSp‘𝑈)
Assertion
Ref Expression
sspph ((𝑈 ∈ CPreHilOLD𝑊𝐻) → 𝑊 ∈ CPreHilOLD)

Proof of Theorem sspph
Dummy variables 𝑥 𝑦 are mutually distinct and distinct from all other variables.
StepHypRef Expression
1 phnv 27053 . . 3 (𝑈 ∈ CPreHilOLD𝑈 ∈ NrmCVec)
2 sspph.h . . . 4 𝐻 = (SubSp‘𝑈)
32sspnv 26965 . . 3 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → 𝑊 ∈ NrmCVec)
41, 3sylan 487 . 2 ((𝑈 ∈ CPreHilOLD𝑊𝐻) → 𝑊 ∈ NrmCVec)
5 eqid 2610 . . . . . . . . . 10 (BaseSet‘𝑈) = (BaseSet‘𝑈)
6 eqid 2610 . . . . . . . . . 10 (BaseSet‘𝑊) = (BaseSet‘𝑊)
75, 6, 2sspba 26966 . . . . . . . . 9 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → (BaseSet‘𝑊) ⊆ (BaseSet‘𝑈))
87sseld 3567 . . . . . . . 8 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → (𝑥 ∈ (BaseSet‘𝑊) → 𝑥 ∈ (BaseSet‘𝑈)))
97sseld 3567 . . . . . . . 8 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → (𝑦 ∈ (BaseSet‘𝑊) → 𝑦 ∈ (BaseSet‘𝑈)))
108, 9anim12d 584 . . . . . . 7 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → ((𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈))))
111, 10sylan 487 . . . . . 6 ((𝑈 ∈ CPreHilOLD𝑊𝐻) → ((𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈))))
1211imp 444 . . . . 5 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈)))
13 eqid 2610 . . . . . . . 8 ( +𝑣𝑈) = ( +𝑣𝑈)
14 eqid 2610 . . . . . . . 8 ( −𝑣𝑈) = ( −𝑣𝑈)
15 eqid 2610 . . . . . . . 8 (normCV𝑈) = (normCV𝑈)
165, 13, 14, 15phpar2 27062 . . . . . . 7 ((𝑈 ∈ CPreHilOLD𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈)) → ((((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2) + (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2)) = (2 · ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2))))
17163expb 1258 . . . . . 6 ((𝑈 ∈ CPreHilOLD ∧ (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈))) → ((((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2) + (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2)) = (2 · ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2))))
1817adantlr 747 . . . . 5 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈))) → ((((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2) + (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2)) = (2 · ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2))))
1912, 18syldan 486 . . . 4 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2) + (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2)) = (2 · ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2))))
20 eqid 2610 . . . . . . . . . . . 12 ( +𝑣𝑊) = ( +𝑣𝑊)
216, 20nvgcl 26859 . . . . . . . . . . 11 ((𝑊 ∈ NrmCVec ∧ 𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
22213expb 1258 . . . . . . . . . 10 ((𝑊 ∈ NrmCVec ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
233, 22sylan 487 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
24 eqid 2610 . . . . . . . . . . 11 (normCV𝑊) = (normCV𝑊)
256, 15, 24, 2sspnval 26976 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻 ∧ (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)))
26253expa 1257 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)))
2723, 26syldan 486 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)))
2827oveq1d 6564 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦))↑2))
296, 13, 20, 2sspgval 26968 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( +𝑣𝑊)𝑦) = (𝑥( +𝑣𝑈)𝑦))
3029fveq2d 6107 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦)))
3130oveq1d 6564 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2))
3228, 31eqtrd 2644 . . . . . 6 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2))
33 eqid 2610 . . . . . . . . . . . 12 ( −𝑣𝑊) = ( −𝑣𝑊)
346, 33nvmcl 26885 . . . . . . . . . . 11 ((𝑊 ∈ NrmCVec ∧ 𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
35343expb 1258 . . . . . . . . . 10 ((𝑊 ∈ NrmCVec ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
363, 35sylan 487 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
376, 15, 24, 2sspnval 26976 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻 ∧ (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)))
38373expa 1257 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)))
3936, 38syldan 486 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)))
406, 14, 33, 2sspmval 26972 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( −𝑣𝑊)𝑦) = (𝑥( −𝑣𝑈)𝑦))
4140fveq2d 6107 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦)))
4239, 41eqtrd 2644 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦)))
4342oveq1d 6564 . . . . . 6 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2))
4432, 43oveq12d 6567 . . . . 5 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) + (((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦))↑2)) = ((((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2) + (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2)))
451, 44sylanl1 680 . . . 4 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) + (((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦))↑2)) = ((((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2) + (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2)))
466, 15, 24, 2sspnval 26976 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻𝑥 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑥) = ((normCV𝑈)‘𝑥))
47463expa 1257 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ 𝑥 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑥) = ((normCV𝑈)‘𝑥))
4847adantrr 749 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘𝑥) = ((normCV𝑈)‘𝑥))
4948oveq1d 6564 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘𝑥)↑2) = (((normCV𝑈)‘𝑥)↑2))
506, 15, 24, 2sspnval 26976 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻𝑦 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑦) = ((normCV𝑈)‘𝑦))
51503expa 1257 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑦) = ((normCV𝑈)‘𝑦))
5251adantrl 748 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘𝑦) = ((normCV𝑈)‘𝑦))
5352oveq1d 6564 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘𝑦)↑2) = (((normCV𝑈)‘𝑦)↑2))
5449, 53oveq12d 6567 . . . . . 6 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2)) = ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2)))
551, 54sylanl1 680 . . . . 5 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2)) = ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2)))
5655oveq2d 6565 . . . 4 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (2 · ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2))) = (2 · ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2))))
5719, 45, 563eqtr4d 2654 . . 3 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) + (((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦))↑2)) = (2 · ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2))))
5857ralrimivva 2954 . 2 ((𝑈 ∈ CPreHilOLD𝑊𝐻) → ∀𝑥 ∈ (BaseSet‘𝑊)∀𝑦 ∈ (BaseSet‘𝑊)((((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) + (((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦))↑2)) = (2 · ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2))))
596, 20, 33, 24isph 27061 . 2 (𝑊 ∈ CPreHilOLD ↔ (𝑊 ∈ NrmCVec ∧ ∀𝑥 ∈ (BaseSet‘𝑊)∀𝑦 ∈ (BaseSet‘𝑊)((((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) + (((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦))↑2)) = (2 · ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2)))))
604, 58, 59sylanbrc 695 1 ((𝑈 ∈ CPreHilOLD𝑊𝐻) → 𝑊 ∈ CPreHilOLD)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 383   = wceq 1475  wcel 1977  wral 2896  cfv 5804  (class class class)co 6549   + caddc 9818   · cmul 9820  2c2 10947  cexp 12722  NrmCVeccnv 26823   +𝑣 cpv 26824  BaseSetcba 26825  𝑣 cnsb 26828  normCVcnmcv 26829  SubSpcss 26960  CPreHilOLDccphlo 27051
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1713  ax-4 1728  ax-5 1827  ax-6 1875  ax-7 1922  ax-8 1979  ax-9 1986  ax-10 2006  ax-11 2021  ax-12 2034  ax-13 2234  ax-ext 2590  ax-rep 4699  ax-sep 4709  ax-nul 4717  ax-pow 4769  ax-pr 4833  ax-un 6847  ax-resscn 9872  ax-1cn 9873  ax-icn 9874  ax-addcl 9875  ax-addrcl 9876  ax-mulcl 9877  ax-mulrcl 9878  ax-mulcom 9879  ax-addass 9880  ax-mulass 9881  ax-distr 9882  ax-i2m1 9883  ax-1ne0 9884  ax-1rid 9885  ax-rnegex 9886  ax-rrecex 9887  ax-cnre 9888  ax-pre-lttri 9889  ax-pre-lttrn 9890  ax-pre-ltadd 9891
This theorem depends on definitions:  df-bi 196  df-or 384  df-an 385  df-3or 1032  df-3an 1033  df-tru 1478  df-ex 1696  df-nf 1701  df-sb 1868  df-eu 2462  df-mo 2463  df-clab 2597  df-cleq 2603  df-clel 2606  df-nfc 2740  df-ne 2782  df-nel 2783  df-ral 2901  df-rex 2902  df-reu 2903  df-rab 2905  df-v 3175  df-sbc 3403  df-csb 3500  df-dif 3543  df-un 3545  df-in 3547  df-ss 3554  df-nul 3875  df-if 4037  df-pw 4110  df-sn 4126  df-pr 4128  df-op 4132  df-uni 4373  df-iun 4457  df-br 4584  df-opab 4644  df-mpt 4645  df-id 4953  df-po 4959  df-so 4960  df-xp 5044  df-rel 5045  df-cnv 5046  df-co 5047  df-dm 5048  df-rn 5049  df-res 5050  df-ima 5051  df-iota 5768  df-fun 5806  df-fn 5807  df-f 5808  df-f1 5809  df-fo 5810  df-f1o 5811  df-fv 5812  df-riota 6511  df-ov 6552  df-oprab 6553  df-mpt2 6554  df-1st 7059  df-2nd 7060  df-er 7629  df-en 7842  df-dom 7843  df-sdom 7844  df-pnf 9955  df-mnf 9956  df-ltxr 9958  df-sub 10147  df-neg 10148  df-grpo 26731  df-gid 26732  df-ginv 26733  df-gdiv 26734  df-ablo 26783  df-vc 26798  df-nv 26831  df-va 26834  df-ba 26835  df-sm 26836  df-0v 26837  df-vs 26838  df-nmcv 26839  df-ssp 26961  df-ph 27052
This theorem is referenced by:  ssphl  27157  hhssph  27515
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