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H[H
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8

x ≥
1/>4959:;4<•?r73Lh
( )
( )
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Q €u v ≥
1
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8 • 8 •
• • 8
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• •
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H[H
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19SWZ4?rg>4959:;4<73F:]L 
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R6_Jo9@4<7ƒ47NHOP
Q
α β
FZ 
( )
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•8
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 ^49c4<59:;4<7=>497qL9
( ) ( )
8 8 8 • €x x x+ − + − + =
Q
( ) ( )
• ‰ • ‰ • €x x x x+ − + − + =
#93H7=HZ4?C=J7<d473O„F:]L49c4<59:;4<7=>49?@7~o9@4<7tD79:T4<L9J7
4C2QFEo9hLM359:;4<7=>49XN4<4CW59j79SEL?C259:;4<7=>497qL9DC73ˆS_7
59Y71
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F:]L79Z9Hl4sS3LYL?qXjO3S1
01H[H59:;4<7=>49
(
)
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t
t x t x

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( ) ( )
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Qo93H
7=HZ4=373O„F:]L57O3S
01@1H[H59:;4<7=>49O3S 

• 8 8 ‰ • 8 8x x x x+ − = + − + −
#$#%
9…4ˆ‹7 Fn7
8t x= −
Q577=\79C49
• 8 ‰ • 8x x t t x+ = + + +
Œ8•
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8x t= −
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( ) ( )

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( ) ( )

( )
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= − + + −
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F:]LDjLFqL9
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59:;4<7=>49?@7~DCo9H<HCH4hL9J4<73BNHFn749HGSŽ459j?C7>DDPHsS34
9l<Hc3LYLŽ459jFZF:3?G9l
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• •‰ ‰



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u v u w
u uv vw wu
v uv vw wu u v v w
w uv vw wu
v w u w
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− = + + ⇔ + + =
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 
− = + +
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 
Q<H[H9l
73F:]L 
‰€ •‰”
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u x= ⇔ =
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
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+ = +

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8•
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8 8 8 8x x x x x x x x+ − + − = − + + −
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31
• •
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g1

Œ ••Œ• • ‰ ‰x x x x+ − = +
L1


3•H[H59:;4<7=>494’•
g•>DLYL<HY7=KLM34FZ59:;4<7=>49Lh4<9HlD 
••

”‘”‘
mx
xxxx
+
=−−+−+
3•H[H59:;4<7=>49?uHD’•‰
g•>DLYL<HY7=KLM3DFZ59:;4<7=>49Lh4<9HlD1
/CH7…57:;4<7v
‰•
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••
xxxx −+=−+ 8


8

••
8‘‰•••‰8‰•

−+++=+++ xxxxx
‘•

•88€• xxx =+−−
—•>DDFZQ59:;4<7=>49O3SLh4<9HlD
mxxxx =−++−++ •–•Œ8Œ–8
–•>DDFZ59:;4<7=>49O3SLh4<9HlD 

8•8••Œ8Œ8•8 −=−++−++ xxxx
••
8‘•
8•–•Œ•Œ–• −=−++−++ xxxx
8—•
•8Œ•—88••

xxxx +=++
8–•
•8Œ8€8•

−=−+ xxxx
8”•
€8•888•••8••
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8•
‰•
8

=

+
x
x
x
Œ8•
•8•


−− 8
‰•
88
8
88
8
•••
8‘‰•••‰8‰•

−+++=+++ xxxxx
•••
8‘‰•••‰8‰•

−+++=+++ xxxxx
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α
FZ59:;4<7=>49O3SLh
4<9HlD
•8•Œ•Œ

8
•‰Œ‰•8•Œ‰Œ −+=

+
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x
x
xxx
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8‘
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+
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y
y
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+
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x
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••
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‰”•
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=+++−+ xxxx
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x
n7Ž459j
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−=−+ txx
Œ••
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tt
tt
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8
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8
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xxxx
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•‘
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8•
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t
t
tt
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uH7’88‰

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{ }
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vuvuvu
vu
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=


S
•••
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=
−+
+
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‰•
88
8
88
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8
8
8

t
t
tt
ttt
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8

8
=⇒= xt
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x
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•‘•>D7_7L[LYL<HY7=K79vLLM3793DOP
α
FZ59:;4<7=>49O3SLh
4<9HlD
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8
•‰Œ‰•8•Œ‰Œ −+=

+
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x
x
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>
−≤
⇔≠−≥


+
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x
x
xxx
Œ8•
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−−=
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8
ay
ay
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+

8

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ˆ’¤8
• Wž€

ˆž‰
• W¡€

ˆ¡¤8
3••‹7o9[4}4<Wž€?uHˆŸ‰Q73Lh 
•8•Œ‰Œ +− xx
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ˆ

 •ˆ ‰ W

’€ Œ••
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>++=

• uHW’¤3 •Q73Lh
• 3¡¤• 9:;4<7=>49Œ8•Lh4<9HlD
–•8•8Œ•8
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+++=−++== aaaxx
• 3Ÿ¤• 9:;4<7=>49Œ8•Lh4<9HlD 
–•8

8
++−== aaxx
3OSW=3 
• rS3¡¤• Œ8•Lh•4<9HlDBC 
••8‚–•8
••
+−−=+++= aaxaax
• rS3’¤• Œ8•Lh•4<9HlDBC 
8‰8‚8 −=−= xx
• rS¤•¡3¡8 Œ8•Lh•4<9HlDBC
••8‚–•8
••
+−−=++−= aaxaax
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