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Theorem sspph 27710
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 27669 . . 3 (𝑈 ∈ CPreHilOLD𝑈 ∈ NrmCVec)
2 sspph.h . . . 4 𝐻 = (SubSp‘𝑈)
32sspnv 27581 . . 3 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → 𝑊 ∈ NrmCVec)
41, 3sylan 488 . 2 ((𝑈 ∈ CPreHilOLD𝑊𝐻) → 𝑊 ∈ NrmCVec)
5 eqid 2622 . . . . . . . . . 10 (BaseSet‘𝑈) = (BaseSet‘𝑈)
6 eqid 2622 . . . . . . . . . 10 (BaseSet‘𝑊) = (BaseSet‘𝑊)
75, 6, 2sspba 27582 . . . . . . . . 9 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → (BaseSet‘𝑊) ⊆ (BaseSet‘𝑈))
87sseld 3602 . . . . . . . 8 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → (𝑥 ∈ (BaseSet‘𝑊) → 𝑥 ∈ (BaseSet‘𝑈)))
97sseld 3602 . . . . . . . 8 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → (𝑦 ∈ (BaseSet‘𝑊) → 𝑦 ∈ (BaseSet‘𝑈)))
108, 9anim12d 586 . . . . . . 7 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) → ((𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈))))
111, 10sylan 488 . . . . . 6 ((𝑈 ∈ CPreHilOLD𝑊𝐻) → ((𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈))))
1211imp 445 . . . . 5 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥 ∈ (BaseSet‘𝑈) ∧ 𝑦 ∈ (BaseSet‘𝑈)))
13 eqid 2622 . . . . . . . 8 ( +𝑣𝑈) = ( +𝑣𝑈)
14 eqid 2622 . . . . . . . 8 ( −𝑣𝑈) = ( −𝑣𝑈)
15 eqid 2622 . . . . . . . 8 (normCV𝑈) = (normCV𝑈)
165, 13, 14, 15phpar2 27678 . . . . . . 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 1266 . . . . . 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 751 . . . . 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 487 . . . 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 2622 . . . . . . . . . . . 12 ( +𝑣𝑊) = ( +𝑣𝑊)
216, 20nvgcl 27475 . . . . . . . . . . 11 ((𝑊 ∈ NrmCVec ∧ 𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
22213expb 1266 . . . . . . . . . 10 ((𝑊 ∈ NrmCVec ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
233, 22sylan 488 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
24 eqid 2622 . . . . . . . . . . 11 (normCV𝑊) = (normCV𝑊)
256, 15, 24, 2sspnval 27592 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻 ∧ (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)))
26253expa 1265 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥( +𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)))
2723, 26syldan 487 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)))
2827oveq1d 6665 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦))↑2))
296, 13, 20, 2sspgval 27584 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( +𝑣𝑊)𝑦) = (𝑥( +𝑣𝑈)𝑦))
3029fveq2d 6195 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦)))
3130oveq1d 6665 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑈)‘(𝑥( +𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2))
3228, 31eqtrd 2656 . . . . . 6 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘(𝑥( +𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( +𝑣𝑈)𝑦))↑2))
33 eqid 2622 . . . . . . . . . . . 12 ( −𝑣𝑊) = ( −𝑣𝑊)
346, 33nvmcl 27501 . . . . . . . . . . 11 ((𝑊 ∈ NrmCVec ∧ 𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
35343expb 1266 . . . . . . . . . 10 ((𝑊 ∈ NrmCVec ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
363, 35sylan 488 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊))
376, 15, 24, 2sspnval 27592 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻 ∧ (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)))
38373expa 1265 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥( −𝑣𝑊)𝑦) ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)))
3936, 38syldan 487 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)))
406, 14, 33, 2sspmval 27588 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (𝑥( −𝑣𝑊)𝑦) = (𝑥( −𝑣𝑈)𝑦))
4140fveq2d 6195 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑈)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦)))
4239, 41eqtrd 2656 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦)) = ((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦)))
4342oveq1d 6665 . . . . . 6 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘(𝑥( −𝑣𝑊)𝑦))↑2) = (((normCV𝑈)‘(𝑥( −𝑣𝑈)𝑦))↑2))
4432, 43oveq12d 6668 . . . . 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 682 . . . 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 27592 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻𝑥 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑥) = ((normCV𝑈)‘𝑥))
47463expa 1265 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ 𝑥 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑥) = ((normCV𝑈)‘𝑥))
4847adantrr 753 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘𝑥) = ((normCV𝑈)‘𝑥))
4948oveq1d 6665 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘𝑥)↑2) = (((normCV𝑈)‘𝑥)↑2))
506, 15, 24, 2sspnval 27592 . . . . . . . . . 10 ((𝑈 ∈ NrmCVec ∧ 𝑊𝐻𝑦 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑦) = ((normCV𝑈)‘𝑦))
51503expa 1265 . . . . . . . . 9 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ 𝑦 ∈ (BaseSet‘𝑊)) → ((normCV𝑊)‘𝑦) = ((normCV𝑈)‘𝑦))
5251adantrl 752 . . . . . . . 8 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((normCV𝑊)‘𝑦) = ((normCV𝑈)‘𝑦))
5352oveq1d 6665 . . . . . . 7 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → (((normCV𝑊)‘𝑦)↑2) = (((normCV𝑈)‘𝑦)↑2))
5449, 53oveq12d 6668 . . . . . 6 (((𝑈 ∈ NrmCVec ∧ 𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2)) = ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2)))
551, 54sylanl1 682 . . . . 5 (((𝑈 ∈ CPreHilOLD𝑊𝐻) ∧ (𝑥 ∈ (BaseSet‘𝑊) ∧ 𝑦 ∈ (BaseSet‘𝑊))) → ((((normCV𝑊)‘𝑥)↑2) + (((normCV𝑊)‘𝑦)↑2)) = ((((normCV𝑈)‘𝑥)↑2) + (((normCV𝑈)‘𝑦)↑2)))
5655oveq2d 6666 . . . 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 2666 . . 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 2971 . 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 27677 . 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 698 1 ((𝑈 ∈ CPreHilOLD𝑊𝐻) → 𝑊 ∈ CPreHilOLD)
Colors of variables: wff setvar class
Syntax hints:  wi 4  wa 384   = wceq 1483  wcel 1990  wral 2912  cfv 5888  (class class class)co 6650   + caddc 9939   · cmul 9941  2c2 11070  cexp 12860  NrmCVeccnv 27439   +𝑣 cpv 27440  BaseSetcba 27441  𝑣 cnsb 27444  normCVcnmcv 27445  SubSpcss 27576  CPreHilOLDccphlo 27667
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1722  ax-4 1737  ax-5 1839  ax-6 1888  ax-7 1935  ax-8 1992  ax-9 1999  ax-10 2019  ax-11 2034  ax-12 2047  ax-13 2246  ax-ext 2602  ax-rep 4771  ax-sep 4781  ax-nul 4789  ax-pow 4843  ax-pr 4906  ax-un 6949  ax-resscn 9993  ax-1cn 9994  ax-icn 9995  ax-addcl 9996  ax-addrcl 9997  ax-mulcl 9998  ax-mulrcl 9999  ax-mulcom 10000  ax-addass 10001  ax-mulass 10002  ax-distr 10003  ax-i2m1 10004  ax-1ne0 10005  ax-1rid 10006  ax-rnegex 10007  ax-rrecex 10008  ax-cnre 10009  ax-pre-lttri 10010  ax-pre-lttrn 10011  ax-pre-ltadd 10012
This theorem depends on definitions:  df-bi 197  df-or 385  df-an 386  df-3or 1038  df-3an 1039  df-tru 1486  df-ex 1705  df-nf 1710  df-sb 1881  df-eu 2474  df-mo 2475  df-clab 2609  df-cleq 2615  df-clel 2618  df-nfc 2753  df-ne 2795  df-nel 2898  df-ral 2917  df-rex 2918  df-reu 2919  df-rab 2921  df-v 3202  df-sbc 3436  df-csb 3534  df-dif 3577  df-un 3579  df-in 3581  df-ss 3588  df-nul 3916  df-if 4087  df-pw 4160  df-sn 4178  df-pr 4180  df-op 4184  df-uni 4437  df-iun 4522  df-br 4654  df-opab 4713  df-mpt 4730  df-id 5024  df-po 5035  df-so 5036  df-xp 5120  df-rel 5121  df-cnv 5122  df-co 5123  df-dm 5124  df-rn 5125  df-res 5126  df-ima 5127  df-iota 5851  df-fun 5890  df-fn 5891  df-f 5892  df-f1 5893  df-fo 5894  df-f1o 5895  df-fv 5896  df-riota 6611  df-ov 6653  df-oprab 6654  df-mpt2 6655  df-1st 7168  df-2nd 7169  df-er 7742  df-en 7956  df-dom 7957  df-sdom 7958  df-pnf 10076  df-mnf 10077  df-ltxr 10079  df-sub 10268  df-neg 10269  df-grpo 27347  df-gid 27348  df-ginv 27349  df-gdiv 27350  df-ablo 27399  df-vc 27414  df-nv 27447  df-va 27450  df-ba 27451  df-sm 27452  df-0v 27453  df-vs 27454  df-nmcv 27455  df-ssp 27577  df-ph 27668
This theorem is referenced by:  ssphl  27773  hhssph  28131
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