2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
$?s
?B [±s 
? c±sD'? ?#?¨ 
?y
 ±sD ' ? ?¥
n1 ?
^ ù? V?f
)(xfy = 
? ) |
¤  ′¥ ù5 bf
0
x
)(xfy = 
0
xx = ) | ¤ ′ ? ?
a
^ ? 
′ii±4?

¥'
Y
L
^
0
xx = ) ¥f
9

)()()(
000
xfxxfxf+=?  ?í ?
a
§
1?|'1?1μb
0
x
[  ) | ¤v′ f ? ?s 
0
x )(xfy =  ?í

0
x
),(
0
δxN
#×
¥±4?
?/

!)(xf  ) V?  ) |¤v ′ '
0
x
0
x ),(
0
δxN
=¥
?ix )?μ )()(
0
xfxf ≤ ?N V?
0)()(
0
≤?=? xfxff ' ),(
0
δxN
=
ê ?
H
f
0
x
)(xf |′Ml?
^ V?
? 
0
xx > 0
)()(
0
00

+
=
xx
xfxxf
x
f
b
?K¥ ??L¤?
0lim
0

+
→?
x
f
x
 b0)(
0


+
xf
? 5
0
xx< 0
)()(
0
0

=
xx
xfxf
x
f
b
0lim
0

→?
x
f
x
 0)(
0


xf

!·° Iù
T? www.tsinghuatutor.com - 1 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
?
^á
ìμ i O b?N?
?L
^n
? ?¥2
b
0)(
0


xf 0)(
0


xf
0)(
0
=

xf
?n
? ? V[ °¤??
,?? ? i O V[ ? ?+ ?±sD '? ?b 

±s?′? ?
? ? n
? ? 'FSNBU ? ? V?f
|¤′¥A1Hq


! )(xf
@° 

#× ),(
0
δxN
=μ?li O
),(
0
δxNx∈? μ )()(
0
xfxf ≤ ))(
0
xf≥   °
 ) V?5 b
0
x 0)(
0
=

xf
è £
ü?
,?? ?
 ?
,?? ?
!f
)(xfy = 
 V?i O],[ ba
0)()( <
′′
+
bfaf b5A ),(
0
bax ∈? 
P¤
 )μ

ü ML
b0)(
0
=

xf
0
x

±
^ )(xf


?s| ?ba,0)( <

+
af ? ?9h?
5  )h

[)(xf ax = ax = ?
^ )(xf ¥ Kl′ ? 7
)(,0)( xfbf >

 bx = ) 9F 5 bx = g?
^Kl′? b
y N V?f
Aμ Kl ′?)(xf ),(
0
bax ∈ ?n
? ? 'μ
0)(
0
=

xf b
£
! 0)( <

+
af O 0)( >

bf
6B f ? h???£
ü
'μ
0
)()(
lim)( <
=

+

+
ax
afxf
af
ax

?K? l  0
1
>?ε  0
1
>?δ 
P?
1
0 δ<?< ax
H

!·° Iù
T? www.tsinghuatutor.com - 2 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
μ
11
)(
)()(
)( εε +

<
<?

++
af
ax
afxf
af b
| 0)(
2
1
1
>

=
+
afε 5μ
0))((
2
1
)()( <?

<?
+
axafafxf 
' )()( afxf < y N )(af ?
^ )(xf 
 ¥Kl′ b],[ ba
6?? μ 0)( >

bf 5 0
2
>?ε b 0
2
>?δ 
P?
2
0 δ<?< xb
HAμ
22
)(
)()(
)( εε +

<
<?


bf
bx
bfxf
bf b
+Y | 0)(
2
1
2
>

=
bfε 5μ
0))((
2
3
)()( <?

<?
bxbfbfxf 
' )()( bfxf < byN )(bf g?
^ )(xf 
¥ K
l′b
],[ ba
y1 )(xf 
 V? 5A ?? ?KvKl ′? ?+ YAμ
P¤
],[ ba
)(
0
xf 1 )(xf 
¥Kl′7 O
'i
],[ ba
bxax ≠≠
00
,),(
0
bax ∈ ? n
? ? A μ
0)(
0
=

xf b
? ? 
:? ? 3PMMF

!f
)(xfy =
@ °
 ?? ],[ ba

!·° Iù
T? www.tsinghuatutor.com - 3 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
°
= V? ),( ba
° )()( bfaf = b
5 ),( ba∈?ξ 
P¤ 0)( =

ξf ' ξ=x )μ

ü M
L
b
}£~ )(xf 
 ?? 5A
 |¤Kv Kl′ y 1],[ ba
)()( bfaf =  ? )(xf ¥K vKl′  
? | ¤ 5],[ ba
Cxf ≡)(  (μ],[ bax∈? 0)( =

xf b?5 )(xf
¥KvKl′?à
μ=?-B
=? |¤?^
!],[ ba
P¤ )(max)(
],[
xff
bax∈
=ξ ?y1 )(xf  V? )(ξf A
1
=¥v′??),( ba
n
? ?¤? 0)( =

ξf b
?
,? ?# -
¥?
,?? ?¥
5?
T ( 1μ

ü M L¥ sH qb ?
@?
?? ?¥Hq
H2
9 V
? ?b
? ?  ?ì μ °±s?′? ? -BHSBOHF

!
@)(xf
°
 ??  °
= V?b],[ ba ),( ba
5 ),( ba∈?ξ
P¤ 
ab
afbf
f
=

)()(
)(ξ }£~
!
? ))(,( afaA D? ))(,( bfbB -W¥?1 AB 5
AB
K
ab
afbf
=
)()(
 AB ¥°LZ?1
)(
)()(
)()( ax
ab
afbf
afxy?
=? 
|£ùf


!·° Iù
T? www.tsinghuatutor.com - 4 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
)()()( xyxfxF?= 
)(
)()(
)()( ax
ab
afbf
afxf?
= 
5 

@
:? ?¥Hq O
?
^
)(xF ],[ ba
0)(,0)( == bFaF ),( ba∈?ξ 
0)( =

ξF '
ab
afbf
f
=

)()(
)(ξ b
? ?ì μ °±s?′? ?
^
:? ? 3PMMF
¥éB??Z £
üZE
^YV?
? £ ùf
 /
,? ? ¥ Hq V 7 ¤ ? 2T bi O 
T Vμ ? / ? N V
r
T
))(()()( abfafbf?

=? ξ
)))((( ababaf+= θ  )10( <<θ  

))(()()(
00
xxfxfxf?

+= ξ 

hfxfhxf )()()(
00
ξ

+=+ 
?±s?′ ? ?¥£
ü
^5? ?£ ùf
[ 7/?¨
:? ?¥H q?
2
b
? ?±s?′? ? V°¤¤ ?w
?/
w
 ?μ),( bax∈? 0)( =

xf 5 cxf =)(   ?
1è
bc
w
 ? μ),( bax∈? )()( xgxf

=

5
=A

),( ba
cxgxf += )()( b? O??
 w L )(xfy = D
)(xgy = μB?
? ),(),,(
000
baxyx ∈
Hμ
)()( xgxf = b

!·° Iù
T? www.tsinghuatutor.com - 5 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
w
 ? )(xf


μ ? 5
 ¥ ?i
? i


P¤
],[ ba ],[ ba
21
,xx
0>L
1212
)()( xxLxfxf?≤? 
? ? 1 ?
 Gè
b 
? éB?μL 10 << L 5?" ¥ )(xfy =
@ a
ê?
`e ?ba
ê?`e ??
?' [?1 p¥
= ?
w
 ? ),( bax∈?  0)( ≥

xf 5 )(xfy = 
? ? d?ì
9F O),( ba 0)( >

xf
H )(xfy = ? ì??
9F b7 ? 0)( ≤

xf
H 0)( <′ xf
 )(xfy = d?ì ? ì
??h
b
? ?ì μ °?′? ?¥
?è¨×1?
^
 
? )(xfy = 
 )¥ |′?
 Vw? í
)
1
x
1
x )(xf
¥ |′?
^
^B Ho y
íp 
@? ? Hq¥ )(xf  uW


? ?  e?T¨b
],[ ba
 
 ?ì μ °?′? ?  )(xfy = ¥f
| ′
9
 D ?
|
′-Wq 
BV B
b

? ?  O?′? ? $BVDIZ
 ?T )(xf )(xg
@ 
> uW
 ?? 
 7 uW
= V? O],[ ba ),( ba
0)( ),()( ≠

≠ xgagbg 5 7 uW
=à
iB?),( ba ξ
P¤
)(
)(
)()(
)()(
ξ
ξ
g
f
agbg
afbf


=
 
±sD'? ?¥+il
 ± s D+?' ? ?μ"
ü A¥+i l
3? t+il | μù? á
ì
y ?A1¥°4?? a
Mb


!·° Iù
T? www.tsinghuatutor.com - 6 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
  ? V[éB?
± I )(xf
@
I
1Hq
H
:? ?D ? ì μ °? ? ?
¥ ξ? μ·B?$?
@
I
1Hq
Hμ
??]¥
1
ξ D
2
ξ $

è 
! 11 ?
 5nm,
nm
xxxf )1()(?= )(xf

 

=
,??
1 #
b
 "
b #
b $
b %
b
}3~? ?ê[1 #
b
 ?
:? ? 0)1()0( == ff yNà
iB?
)1,0(∈ξ
P 0)( =

ξf ?
11
)1()1()(

=

nmnm
xnxxmxxf 
 )()1(
11
nxmxmxx
nm
=

b
7 0)( =

xf ?
H)1,0(∈x
0)1(
11
≠?
nm
xx ¤ )1,0(
0

+
=
nm
m
x 
1·B?'
0
x=ξ 1 )(xf

¥·B
,?b
è 
! )(xf
^?
ù 1 ¥?
ùf
 
= V?  O]1,0[
,0)1( =f 
7 )(max
]1,0[
xfM
x∈
= 
k£
ü i ( )2,1∈ξ 
P¤
Mf 2)( ≥

ξ b
}£~
n5y )(xf
^?
ù1 ¥?
ùf
5o?£
ü
 ( )1,0
0
∈ξ
P¤ Mf 2)(
0


ξ b
¨ -BHSBOHF?′? ? 
? )(xf 
= V?5A
= ???y]1,0[ ]1,0[

!·° Iù
T? www.tsinghuatutor.com - 7 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
,0)0()1( == ff 
5o
i
P¤),(10∈
M
x )(max)(
]1,0[
xfMxf
x
M

== b

KvKl′?
? |¤
 uW ),0(
M
x  )1)((0
2 M
xfM?

=?± ξ 
 uW )1,(
M
x 
M
xfM )(0
1
ξ

=± 
( )
M
x,0
1
∈ξ  ( )1,
2 M
x∈ξ 


TsY | '′aMF¤?
)1)(()(2
21 MM
xfxfM?

+

= ξξ 
7
{ })(,)(max)(
210
ξξξ fff
′′
=


5μ ( )1,0
0
∈ξ N
Hμ??
T )(2
0
ξfM

≤ 
yNi ( )2,11
0
∈+= ξξ 
P¤ Mf 2)( ≥

ξ 
 T 1
 h ?| ?ì μ °?′? ?¥ ?w
GQé?£
ü ?|μ ù?
?B×1? ?¥ ?3D?¨b
è 
! )(xf 
μ=¨?
 O]2,1[ 0)2()1( == ff 
£
ü)()1()(
2
xfxxF?= )2,1(
0
∈?x 
P¤
0)(
0
=
′′
xF b

±
^ ?¨
:? ?b)(xF

£ ZE 

 
7
5μ
)()1()()1(2)(
2
xfxxfxxF

+?=

1=x 0)1( =

F 
6?
0)2()2(,0)1( === fFF ?
:? ?
)2,1(
1
∈?ξ 
P¤ 0)(
1
=

ξF  )(xF

 ],[
1
1 ξ
?¨

!·° Iù
T? www.tsinghuatutor.com - 8 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
:? ?5 )2,1(),1(
10
∈=? ξξ x 
P¤
0)(
0
=
′′
xF b
 ZE 

Q£
! 5??
,?? ? -w
V?0)( ≠
′′
xF )(xF
′′
 

 |?| ? ^
! y N0)( >
′′
xF )(xF


1 ?ì ??9
f
b
]2,1[
 I
n? #0)1( =

F )2,1(∈x 
[ 0)( >

xF '
?|¥2
b??
?
:? ? ?
)()2,1( xFx

∈? μ
0)2()1( == FF )2,1(
1
∈?ξ 
P¤
0)(
1
=

ξF ? D

)(xF

?| 2
± ?
^eL
! ?? ? '
A 
P¤)2,1(
0
∈?x 0)(
0
=
′′
xF b
è 
! )13)(12)(1()(?++= xxxxxg 
k ??Z? 0)( =

xg 
=μ+?
L?b)0,1(?
±
^ X?f
)(xg V r
TX
^ y0e?
T??¨ ??f
,?? ?#
:? ?8)
)(xg

¥
,?ù5 7??ü )(xg

p ?)

,? b
}3 ~f

 ?? O V? A ? μ ?
L? 

)(xg ),( +∞?∞ )(xg 0
1
=x
1
2
=x
2
1
3
=x 
3
1
4
=x ?
:? ? )(xg


μ ?
,? )
3
1
,0(
1
∈ξ 
)
2
1
,1(
2
∈ξ  )0,
2
1
(
3
∈ξ b
? )(xg

1 Q[
T Kμ ?
L?y N )(xg

 )0,1(?
= 
μ ?
L?b

!·° Iù
T? www.tsinghuatutor.com - 9 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
è 
! £
ü??
T0>x
24
)1arctan(
22
2
x
x
xx
x
<?+<
++
π
b
}£~
ZE ? o3£
ü??
T0>x
2
1
4
)1arctan(
22
1
2
<
+
<
++
x
x
xx
π

?i?
4
1arctan
π
=  ?i ),0( ∞∈x
7
xxf arctan)( = 5μ
1)1(
)1()(
4
)1arctan(
+
=
+
x
fxf
x
x
π


¨ -BHSBOHF?′? ?5μ]1,1[ x+
)1,1(,
1
1
1)1(
4
)1arctan(
2
+∈
+
=
+
+
x
x
x
ξ
ξ
π

y
2
1
1
x+
1??hf
?
^
2
1
4
)1arctan(
22
1
2
<
+
<
++
x
x
xx
π
b

ZE 
7

!·° Iù
T? www.tsinghuatutor.com - 10 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
xxx
xxxxf
++?
+++=
)22(
4
)1arctan()22()(
2
2
π

0)0( =f

0]
4
)1)[arctan(22(
)22(
4
)1arctan()22()(
>?++=
+?++=

π
π
xx
xxxxf

?
^?
H 'eP§??
T? ?b0>x 0>)(xf
7 0)0(,
24
)1arctan()( =+=?
π
x
xx 
0)(,0
2
1
)1(1
1
)(
2
<?<?
++
=

x
x
x 
'e·§??
T? ?b
è
! ]1,0[)( Cxf ∈ 
= V? O)1,0(
0)1()0( == ff £
üi )1,0(∈ξ
P
0)(')(2 =+ ξξξ ff b
}£~/  ?^£)()(
2
xfxxF =
]1,0[)( CxF ∈ O
= V?)1,0(
O  ?¨
:? ?¤0)1()0( == FF )(xF
i 0)(')1,0( =∈ ξξ F
P '
0)(')(2
2
=+ ξξξξ ff

!·° Iù
T? www.tsinghuatutor.com - 11 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
H]" 0≠ξ ?
^e5¤£b


¨?
ù?f
?

′j?D.?K′??
T?
?y
¨?
ù?f
?
^B ? ×1ù5
??
? ¨S?b ? ? ù5¥ ?

$
^ ?
E?? ? ?±sD '? ? i O
# ??
?l D+il [ # ?
?f
¥?é?
= ?b 7? ?ù5
# ¥S?
^f
# ?

.à=¨ ?

¥
,? ù59h? ù5′D KvKl′ ù5 wL¥ ?j?ù5 DvíLù 5
[#
t??
T¥£
üù5b

f
¥ ?′ù5
 ? l  ? ¥

#×
=μ
0
x )()(
0
xfxf ≤ 
 ))()(
0
xfxf ≥ 
5? )(
0
xf 1f
)(xf ¥B?v l
′b
 v′al′d?1′
Pf
|′¥? ?1′?b
0
x
 B ? V?f
 ) |¤′ ¥A1Hq
^
0
xx = 0)(
0
=

xf ?
?
^n:
? ?b
@ 0)(
0
=

xf ¥? ?¥1
0
x )(xf ¥?b
 V+
 A wL′? ) ?Tμ MLA
^

ü MLb
0
x
? ?
′?¥ sHq
? ?  ?B ? sHq

! )(xf 

#×
=μ?l ? )¥9

0
x
0
x
)()()(
0
xfxfxf?=? 
§?í ?M|5
0
x
0
xx = A
1 )(xf ¥ ′?bi O 0)( ≥? xf
H 1l′? 7
0
x
0)( ≤? xf
H 1v′?b
0
x
è  p xxf?= 1)(  ]1,1[?
=¥′?b

!·° Iù
T? www.tsinghuatutor.com - 12 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
}3~
≥?
<?
=
11
11
)(
xx
xx
xf ? 0)1( =f ¤
1<x  01)1(1 <?==? xfxf 
1>x  01)1(1 <?==? xfxf 

§?í (μ1=x 0≤?f ?|? 1=x )? ?b
? ?  ?= ? sHq


!)(xf 
 ??
#×
0
x ( ) ( )δδ +?
0000
,,xxxx U
= V ± ) ? ?5?
0
x )(xf


 §M|
H  1
0
x
0
x )(xf ¥
′?i O
 
 ? ( )xxx,
0
δ?∈
H 0)( >

xf 7?
( )δ+∈
00
,xxx
H 0)( <

xf 
0
xx = A1v ′?b 
 
 ? ( )xxx,
0
δ?∈
H 0)( <

xf 7?
( )δ+∈
00
,xxx
H 0)( >

xf 
0
xx = A1l ′?b 
è 
!Z? 03
3
=+? Axx )
A |′
H
 
Z?μB?
L? 
 
Z?μ=??]
L? 
 
Z?μ ???]
L?b
}3 ~
! 5 1 ?Q  [
T K  μ ? ?
L ? b¨ ?
)
?f
¥9h uWD′¥s? f ?b
Axxxf +?= 3)(
3
)(xf
 )1)(1(333)(
2
+=?=

xxxxf

7 0)( =

xf 3¤? 1
1
=x 
1
2
=x
i O
)1,(∞∈x
H 0)( >

xf  )(xf ??9F 
)1,1(?∈x
H 0)( <

xf  )(xf ??h
 
),1( +∞∈x
H 0)( >

xf  )(xf ??9Fb

!·° Iù
T? www.tsinghuatutor.com - 13 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
 ?
^ V? 1
1
=x 1 )(xf ¥v′? 7 1
2
=x 1 )(xf ¥
l′?b )(xf ¥vl′sY1
 
 2)1( +=? Af  2)1(?= Af 
Kv Kl′ (v ?
, l?
,
H )(xfy =  ),1( +∞?
= í
,?
∞=
∞→
)(lim xf
x
' )(xf V )1,(∞
= V |¤ μ
′? ??f
¥
,?? ? V? )(xf ? )1,(∞
=μB?
,?b
0)2)(2()1()1( >?+= AAff 
?N V¤ A?
@ 04
2
>?A ' 2>A 
 
 A ?  ? )(xf ¥K vKl ′μB ?1
,
H'

H04)1()1(
2
=?= Aff
)(xf μ
?
,?N
H 2=A b
 
 ? )1(?f D )1(f |¤s|
H?i?
+∞=
+∞→
)(lim xf
x
?
^ )(xf μ ? ?
,? sYê ?
)1,1(),1,(∞ D ),1( +∞
=N
H 2<A b
 ? ?  ? ? ? sHq
 ?T 0)(
0
=

xf 
0)(
0
<
′′
xf )0(> 5 )(
0
xf 1v′ l′
b
?éB?¥<l sHq1??j?B?a
ób
è  p 543
3
2
)(
23
++?= xxxxf ¥′b
}3~
)2)(1(2462)(
2
=+?=

xxxxxf 

!·° Iù
T? www.tsinghuatutor.com - 14 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
¤?  b1
1
=x 2
2
=x
64)(?=
′′
xxf b 02)1( <?=
′′
f 
[
3
20
)1( =f 1v′y 1 02)2( >=
′′
f 
[
3
19
)2( =f 1l′b

> uWD 7 uW
¥KvK′ù5

> uW
¥KvK′ù5
?)(xf 
 ??
HA ?
μKvK l′b7
μ W?? V??
H p
],[ ba ],[ ba
],[ ba )(xf 
Kv Kl′
H ?
|?? V??#
?)¥f
′?Bé?1?7a ??KvKl′b
],[ ba
è  p 155
345
++?= xxxy ]2,1[?
¥ KvK′ b
}3~5 p?
)3)(1(515205
2234
=+?=

xxxxxxy 
7 0=

y 3¤ ? 0
1
=x  1
2
=x  3
3
=x  O
 ?xxxy 306020
23
+?=
′′
3
x ]2,1[?
b
 0)0( =
′′
y  010)1( <?=
′′
y 
1)0( =y  2)1( =y 
10)1(?=?y  7)2(?=y 
yN )(xfy = 
¥Kl ′1]2,1[? 10)1(?=?y K v ′
1 2)1( =y b

!·° Iù
T? www.tsinghuatutor.com - 15 - bvD ? S
L 1101 è 62781785
ex 31 ≤≤ £
ü??
T è  
!
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
1lnln)3(ln1
222
≤?≤? xx b
}£~?B??
To?
7
xxxf
2
lnln2)(?=  p )(xf 
¥Kv Kl′b
5 p?b
]3,1[ e
 x
xx
xf ln
22
)(?=


7 0)( =

xf 3? ]3,1[
0
eex ∈= 
 112)()(
0
=?== efxf  0)1( =f 


2
)3(ln)3ln(2)3( eeef?=
2
)3(ln1)3ln1)(3ln(?=?= e
[ 1max
]3,1[
=
∈ ex
f  ?
a
ü 1£ ¥
??
T? ?b
2
]3,1[
)3(ln1min?=
∈ ex
f


f
7 uW
=¥KvKl′

?/?ù5),( ba
  7 u W
=? ?
T ¥£
ü è
#? 7 u W
= ? ?¥f
¥ K v K
l ′ 
/? ù5 b
n5  7 uW
= ? ?¥f
? AμK v′ K l
′byN I3 7 uW
=f
¥K vKl′ù 511A u W
¥ f ? ?¤ˉ
b
),( ba
),( ba
),( ba
B ? f ?/ V? ¨A1 ¥
m 
I3 )(xf 
= ¥
? D/ ?ù
5 8ZE
^
n5 p
= ¥?D ? V?? ??
=¥ 
′? Q?éB? I°
),( ba
),( ba ),( ba
)(xf 
=0 uW
¥9h?[#
??),( ba

!·° Iù
T? www.tsinghuatutor.com - 16 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
§K Axf
ax
=
+

)(lim D Bxf
bx
=

)(lim Ka ? ?f
¥
KvKl′
?D/?b? ?ù5B?
^ uW
=? |¤KvKl′b
è   £
ü  ? i )2,0(∈x ? ???
T
32ln4
2
+≥ xxxx 
}£~
7 32ln4)(
2
+= xxxxxf
I
n )(xf  

= ¥ ? μ| D  ′ ù 5 b 5 p  ? b
22ln44)(+=

xxxf 

7 0)( =

xf 3? )2,0(1
0
∈=x éB? I°
? ?
§K¥ f ?b
 03)(lim
0
>=
+

xf
x

052ln8)(lim
2
>?=

xf
x

? 2
4
)(?=
′′
x
xf  02)(
0
>=
′′
xf yN
)(min0)1(
)2,0(
xff
x∈
== b
?i?" 0)( ≥xf 'e??
T? ?b
è  p xxxf ln)( =  ( )+∞,0
=¥KvKl′b
}3~
)ln2(
2
1
ln
2
1
)( x
x
x
xx
x
xf +=+=


7 0)( =

xf 3¤? ),0(
2
0
+∞∈=
ex 

!·° Iù
T? www.tsinghuatutor.com - 17 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
?
H),0(
2?
∈ ex 0)( <

xf  )(xf ??h 
?
H),(
2
+∞∈
ex 0)( >

xf  )(xf ??9 
?
^ 1
2
0
=ex )(xf ¥l′?
6??
 0lnlim
0
=
+

xx
x
# +∞=
+∞→
xx
x
lnlim 
V[ ? )(xf 
=¥ Kl′1),0( +∞
12
)(

= eef íK
v′b
?  
L=?¨ ù5 ?
L =ù5? μKv l
′  Of
 ?l×
= μ·B
?5??'1Kv l
′?b

 wL¥?jD.?
 ? l  ? w L 
ê? 
 ò?¥ ML
 /
Z 5
aN w L
^? j
¥bm8
  V?f
Vm ?
 A
"x¥9v ? wL )(xfy = ¥ M L|
q
^ ??9¥ ' )(xf

??

6  7j wL ML |
q??h l' )(xf

?? /? ?
^
?j uW ¥×1ZE b7 ? )(xf
′′
i
H  V[ ?¨
¥=¨?
?μ|
? wL
¥?j?b
)(xf
 ? ?  u W I
 ? )0(0)( <>
′′
xf 5 wL
)(xfy =
^? j
¥b
  ?? wL
?j?s¥s???1 wL¥.?b
 ? )(xfy = μ=¨ ?
5? ( ))(,
00
xfx 1.?¥A 1Hq
^
0)(
0
=
′′
xf b? ?.?9 V
C=¨?
?i¥?)b
 ??·  ?f
)(xf  ¥

#×
=  μ@ ¨
¥?
H 
0
x

!·° Iù
T? www.tsinghuatutor.com - 18 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
)(xf ¥,?ù5'1 )(xf

¥ ′?ù 5b yN,?¥
Y E V?v
′?¥
YZEb VB
, ?/
 
 ? 
§?M9h?5)(xf ′
0
x ( ))(,
00
xfx A1 wL
¥.?b)(xfy =
 
 ? )(xf
′′

§ M| 5
0
x ( ))(,
00
xfx A1 wL
)(xfy = ¥.?b
 
? 0)( =
′′
xf 7 0)(
0

′′′
xf
H( ))(,
00
xfx
A1 wL ¥.?b)(xfy =
 ′?D.?÷B??¥2
^ ?/? ?b
 ? ?  ? )(xfy = 

5×
=μ ¨?
 O
0
x n
0)()()(
0
)1(
00
===
′′
=

xfxfxf
n
L 
? 50)(
0
)(
≠xf
n
 
? kn 2=
H 1
0
x )(xf ¥′?
O
H 1l′?0)(
0
)2(
>xf
k
0
x
0)(
0
)2(
<xf
k
H 1v′?
0
x ),2,1( L=k b
 
? 12?= kn
H( ))(,
00
xfx 1 wL )(xfy = ¥
.?b
è 

^?10=x
xeexf
xx
cos2)( ++=
¥′?$
}3~ xeexf
xx
sin2)(=

 0)0( =

f 

!·° Iù
T? www.tsinghuatutor.com - 19 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
 xeexf
xx
cos2)(?+=
′′
 0)0( =
′′
f 
xeexf
xx
sin2)( +?=
′′′
 0)0( =
′′′
f 
xeexf
xx
cos2)(
)4(
++=

04)0(
)4(
>=f 
?? ?  10=x )(xf ¥l′?b
è 
! 5
$b
5
)( xxf =
 "
 10=x )(xf ¥v′?b 
#
 10=x )(xf ¥l′?b
$
 ))0(,0( f 1 wL )(xfy = ¥.?b %
 "
#
$
( ? ?
?b
}3 ~ ?
?
^oμ $
? ?b
0)0()0()0()0(
)4(
==
′′′
=
′′
=

ffff
05)0(
)5(
≠=f
è 
! )(xf 

#×
=μ= ¨ ???
 O0=x 0)0( =

f 
 1
cos1
)(
lim
0
=
′′

x
xf
x
5
#b
 "
 )0(f
^ )(xf ¥v′  
 #
 )0(f
^ )(xf ¥l′
 $
 ))0(,0( f
^ wL )(xfy = ¥.? %
 0=x ?
^
)(xf ¥′?

!·° Iù
T? www.tsinghuatutor.com - 20 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
 ))0(,0( f 9?
^ wL )(xfy = ¥.?b
}3~ ? 1
cos1
)(
lim
0
=
′′

x
xf
x
5 V? 0)0( =
′′
f ? ?@[
a
ü ))0(,0( f 1.?b
?  K¥  ?? ??  ¥

# ×
= Aμ
0
x 0)( >
′′
xf ' ?
)(xf

?
#×
=1? ?9F ?y1 0)0( =f ?
^ ? ? )(xf


§M|'0=x )(xf ?M 9h? O ? YV 7M v
H x
0
x
)(xf ?? hM1?9 ?
^ V[ ? 0=x 1 )(xf ¥ l′?b 'o
μê[ #
? ?b
è £
ü??
T
).1,1(1)1(?>>+≥+ xxx λλ
λ

}£~
! xxxf λ
λ
+= 1)1()( 
ù5M1£
ü,0)( ≥xf  ??
]1)1[()1()(
11
+=?+=

λλ
λλλ xxxf 
7 0)( =

xf ¤? )(xf ¥·B? 0=x b
?
H0<x 0)( <

xf  
?
H0>x 0)( >

xf 
[ 0)0( =f
^ )(xf ¥ l′
9
^Kl′b# 0)0()( =≥ fxf 'μ
xx λ
λ
+≥+ 1)1( b
è 
! )(xf 
 μ=¨?

 O],[ ba )()( bfaf =
£
ü

!·° Iù
T? www.tsinghuatutor.com - 21 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785

iB? ),( ba∈ξ
P
ξ
ξ
ξ

=
′′
b
f
f
)(2
)( 
}£~ ? 3PMMF? ? 
P),(
0
bax ∈? 0)(
0
=

xf 4 3
1£¥?
Tcμ
))(()(2 ξξξ?
′′
=

bff 
?¨M[/£ùf
¥ZE |
 )()()(
2
xfxbxF

=
0)()(
0
== xFbF Q? 3PMMF? ?
),(
0
bx∈?ξ 
P 0)( =

ξF 
)()()()(2)(
2
xfxbxfxbxF
′′
+

=


7 ξ=x 5μ
)()(2 ξξ fb

 )()(
2
ξξ fb
′′
=
? ),(
0
bx∈ξ  b≠ξ yN
)(2))(( ξξξ fbf

=?
′′

'μ
ξ
ξ
ξ

=
′′
b
f
f
)(2
)(  ),( ba∈ξ b
è 
! )(xf 1
=¨ V?f
 O],[ ba
0)(),()( ≠
′′
= xfbfaf 5/

5?p¥
^
% b

" (μ),( bax∈? 0)()( ≠? bfxf b
# )(xf

=??M?j?b),( ba

$à
iB? ),,( ba∈ξ
P¤ 0)( =

ξf b
%à
 B ?
),,( ba∈ξ
P¤ 0)( =ξf b

!·° Iù
T? www.tsinghuatutor.com - 22 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
}3~
n5 "
D $
^¥y1 ?μ ),(
0
bax ∈
P¤
0)()(
0
=? bfxf ' )(xf  ?? ?
μM]f
′5 ?
3PMMF? ? V¤? )(xf ′ μ
?
,? é7 )(xf
′′

= μB?
,? 
?D
),( ba
0)( ≠
′′
xf
±b
?y 1 0)(),()( ≠
′′
= xfbfaf ??
,?? ?? ?
)(xf
′′

=?M|yN #
? ?b?ê
% b),( ba
è 
! ?iè
0>k f

k
e
x
xxf +?= ln)( 
?l×
=¥
,??
1
$ b
"
b #
b $
b %
b
}3~
ex
xf
11
)(?=

μ·B? ex =
0

?  O
H
∞=+∞>=?∞=
+
)(,0)(,)0( fkeff
),0( ex∈ ↑?>

)(,0)( xfxf  )(xf μB ?
,? ),0(
1
ex ∈
),( ∞+∈ ex
H ↓?<

)(,0)( xfxf  )(xf μ B
?
,? yNs?1
$ b),(
2
∞+∈ ex
è 
! )(xf  ),( ∞+?∞
= V ? O 2)(lim =

∞→
xf
x

X?K?
T
[])()1(limlim xfxf
cx
cx
x
x
x
+=
+
∞→∞→


!·° Iù
T? www.tsinghuatutor.com - 23 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
pè
cb
}3~
x
x
cx
cx
+
∞→
lim 
c
cx
cx
c
cx
x
e
cx
c
2
2
22
1lim =
+=
∞→

? -BHSBOHF?′? ?

[ ] 21)(lim)()1(lim =?

=?+
∞→∞→
ξfxfxf
xx

? )1,( +∈ xxξ ? X??
T 5μ 2
2
=
c
e 3
2
2ln
=c 
è 
! £
üba <<0

ba
ab
a
b
+
>
)(2
ln 
}£~1£
a
b
a
b
a
b
+
>
1
)1(2
ln 
 )1(2ln)1(?>+
a
b
a
b
a
b
b
7 )1(2ln)1()(,ttttf
a
b
t+== 
5μ 0)1(,1 => ft 

!·° Iù
T? www.tsinghuatutor.com - 24 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
)1(2ln
1
)(+
+
=

tt
t
t
tf ,0)1( =

f 
0)
1
1(
1
)( >?=
′′
tt
tf 
0)(,0)( >?>

tftf b
víL
  ?g?[/ ? ?víL

 ?iè
C 
P¤ Cxf
x
=
+∞→
)(lim 
Cxf
x
=
∞→
)(lim 5 Cy = 1 )(xfy = ¥

üvíLb

 ? i
P
0
x ∞=
+

)(lim
0
xf
xx
∞=

)(lim
0
xf
xx
5
1
0
xx = )(xfy = ¥<°víLb
è ? wL
1
sin
=
x
x
y ¥víLy1 0
1
sin
lim =
∞→
x
x
x

[ 0=y 1 wL¥

üvíLb?y1 ∞=

1
sin
lim
1
x
x
x

[
1 wL¥ #°víLb1=x

|vé L ?i°L baxy += 
P¤
0))((lim =
±∞→
baxxf
x
5 baxy += 1
)(xfy = ¥|vé Lb
L¨ ?¥ZE  I3
^ ?i K
a
x
xf
x
=
±∞→
)(
lim DK

!·° Iù
T? www.tsinghuatutor.com - 25 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
baxxf
x
=?
±∞→
))((lim b
?oμ a
x
xf
x
=
±∞→
)(
lim ¥i?@[ £|véL¥iQ è 
xxy sin+=  a
x
xf
x
==
∞→
1
)(
lim i?
=?
±∞→
))((lim axxf
x
x
x
sinlim
∞→
?ib

b?i y7
àμ|véLb
è  pf
1
)1)(13(
)(
2
+
=
x
ex
xf
x
¥víLb
}3~ 

∞=
+
=

→→
1
)1)(13(
lim)(lim
2
11
x
ex
xf
x
xx

+∞=
+
=
++
→→
1
)1)(13(
lim)(lim
2
11
x
ex
xf
x
xx

#μ<°víL 1=x


+∞=
+
=
∞→?∞→
1
)1)(13(
lim)(lim
2
x
ex
xf
x
xx

+∞=
+
=
+∞→+∞→
1
)1)(13(
lim)(lim
2
x
ex
xf
x
xx

[í

üvíLb



!·° Iù
T? www.tsinghuatutor.com - 26 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
+∞=
+
=
+∞→+∞→
)1(
)1)(13(
lim
)(
lim
2
xx
ex
x
xf
x
xx

[? +∞→x
H
àμ|víLb
a
xx
ex
x
xf
x
xx
=?=
+
=
∞→?∞→
3
)1(
)1)(13(
lim
)(
lim
2
])([lim kxxfb
x
=
∞→

]3
1
)(13(
[lim
2
x
ex
x
x?
+
=
∞→
)1
x+
1
)1(3)1)(13(
lim
2
+?+
=
∞→
x
xxex
x
x
3
1
13)13(
lim
2
=
+
=
∞→ x
xex
x
x
[∞→x
Hμ|víL
 )1(3 +?= xy 
?víLù5?V
??HKsYé? I3b
8 è5
è Z? xe
x
=?
2
1 ),0( ∞+
=
L?¥
?
1
 b
"
 #
 $
 %

}3~
7 xexf
x
=
2
1)( 0)0( =f ?
012)(
2
=?=

x
exf  p¤?
2
2ln
0
=x 
04)(
2
<?=
′′
x
exf #
^·B?
0
x

!·° Iù
T? www.tsinghuatutor.com - 27 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
OμKv′1
0)2ln1(
2
1
2
2ln
1)
2
2ln
(
2ln
>?==
ef b
?y1 ?K¥ ???∞=
+∞→
)(lim xf
x
i ),
2
1
(
1
∞+∈x
P¤ 0)(
1
<xf yNi
),
2
2ln
(
12
xx ∈

P¤ 0)(
2
=xf b
? )
2
2ln
,0(∈x
H 0)( >

xf  ??9F)(xf
0)0()( => fxf í
,?b
? ),
2
2ln
( ∞+∈x
H 0)( <

xf  ??h
KμB?
,?b)(xf
?
^
^ 
2
x )(xf ),
2
2ln
( ∞+
=¥·B
,?b
8

s?
^
^ 
2
x )(xf ),0( ∞+
=¥·B
L?b
[
? ???|¨?
 )(xf

¥ ???7'5?ó )(xf

¥ ? ?
?HqKíE9
2Tb?
^¨
ArE5
H¥ènpb
è 
! )(xf  =¨ V? B M),0[ ∞+ ),0( ∞+∈x μ
0)( ≠
′′
xf £
ü ),0( ∞+
= wL )(xfy = 
B?
))(,(
00
xfx )¥ MLD? wL" M??í??b
<£>
ZE 
! MLZ?1
))(()()(
000
xxxfxfxy?

+= 
i |£ùf

)()()( xyxfxF?= 
))(()()(
000
xxxfxfxf?

= 

!·° Iù
T? www.tsinghuatutor.com - 28 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
5o?£
ü )(xF
),0( ∞+
=" M?
))(,(
00
xfx ?í
,?b
£
ü 
=?M|b)(xF ),0( ∞+
),()()(
0
xfxfxF


=

0)(
0
=

xF 
0)()( ≠
′′
=
′′
xfxF ?^L
! 0)( >
′′
xF 
0)(
0
>
′′
xF ?
^ 0)(
0
=xF 1 ¥l′? y 1
H
)(xF
0
0 xx<<
0)()(0)( >↓<

xFxFxF 
0
xx>
H 0)()(0)( >↑>

xFxFxF 
' 0)(
0
=xF 1 )(xF ),0( ∞+
=¥Kl′
[ )(0)(
0
xxxF ≠> b£8b

ZE Q£Eb
L
! )(xfy =  ))(,(
00
xfx )¥ MLD? wL" M??

μ B???
01
xx ≠ ?^
! 
¨ -BHSBOHF
01
xx > ],[
10
xx
?′? ? ),(
10
xx∈?ξ 
P¤

01
01
)()(
)(
xx
xfxf
f
=

ξ 
?i? ))(,()),(,(
0011
xfxxfx ? ML
yN?μ
)(
)()(
)(
0
01
01
xfk
xx
xfxf
f

==
=

M
ξ 
? 3PMMF? ?
Ai ),(
01
ξξ x∈? 
P¤
0)(
1
=
′′
ξf ?D 0)( ≠
′′
xf
±b£8b

!·° Iù
T? www.tsinghuatutor.com - 29 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
è 
! )(xf
^ )1,1(?
=¥ ?? f
 O
a
x
xf
x
=
+

)(
lim
0

5 )(xf  )¥?
1
"b0=x
"
b #
a a? b $
0b %
?ib
}3~
a
x
xf
x
xf
x
xf
xxx
==
=
+
→→→
)(
lim
)(
lim
)(
lim
000
#
)(xf  )¥?
1 ab0=x
è £
üZ? 0122
2
=?++ xx
x
àμ
??]
L?
}£~ L
! 0122
2
=?++ xx
x
μ ? ? ??[
?]¥
L
?b 
! 5122)(
2
++= xxxf
x
)(xf ?? ? ?[
?]
¥
,?b
?
^ à
μB?
,?b4)2(ln2)("
2
+=
x
xf
7 v?
,#e Z?àμ
??]¥
L
?b
4)2(ln2)("
2
+=
x
xf
è 
! )(xf
@
[] xxfxf sin2)()(
2
=

+
′′


5
bs?$
"
 ? 0)0( ≠
′′
f 5 0=x A1 )(xfy = ¥′?b
#
 ? 0)0( =

f 5 0=x A1 )(xfy = ¥′?b
$
 ? 0)0( =

f 5 ))0(,0( f A1 wL )(xfy = ¥.?b 
%
 ? 0)0( ≠
′′
f 5 ))0(,0( f A1 wL )(xfy = ¥.?b 

!·° Iù
T? www.tsinghuatutor.com - 30 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
}3~ ? 0)0( =

f ?
[] xxfxf sin2)()(
2
=

+
′′
5 0)0( =
′′
f 
[ ] )()(2cos2)( xfxfxxf
′′

=
′′′

02)0( >=
′′′
f 
yN? ))0(,0( f A1 )(xfy = ¥.?b #
??ê $
b
? 0)0( ≠
′′
f 5 0)0( ≠

f
?
^ "
D %
(?b

±sD'? ?#?¨ ??sDef


ü à
TD
ArE5
?y
 SD 9
D ?
ù?? è è?? dL ?f
? dL? ù5 ? á ¥
9
ˉ?D ?
¥ ?
4 aa
^? V E
¥b 7[
Tf
"?
af
¥L?F
7 ? ¥ 9
 μí [
1¥e ?? ?B? ?ì 8?  ' V
L C [
T
f
¥
′9

 y7¨ B? [
Tf
? / í í
B? dL ?f

?
×1¥
D
m
b
6? f
¥??
ù? K?9|?
ü à
T 5BZMPS

T
ó  ?
G b è ? ? ′ ù5 [# ¨? p K ¥
A r E 5?
^ [
ü à
T1 ?
G 7¤?
tμr¥ZEb
)(xf
)(xp
n
? )(xfy =  ) ¥ V?? D V±?à
Qb  ?í¥
0x 0
x )(xf V
[V
U1
)())(()()(
0000
xxxxxfxfxf?+?

+= α

? )(
0
xx?α 1
H¥í kl
b
0
xx →
 ? 
T V?C9
¥í
′ V |)(xf
))(()()(
000
xxxfxfxf?

+≈ 
?
 ?¥μ )(
0
xx?α ?
@ú1 p5 V
!X
^? D -
0
x x

!·° Iù
T? www.tsinghuatutor.com - 31 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
Wi ξ
P¤
2
0000
))(())(()()( xxfaxxxfxfxf?
′′
+?

+= ξ
? 1 è

Y
L
a
2
1
=a b? ?
^
ü à
T ¥'
±Xb 9
^±s ?′?
?¥éB?w<b
 ¨
ü à
Tn
 ? ? 
ü à
T
!f
)(xf  uW
=  μ ¨?

),( ba 1+n
2
0
0
000
)(
!2
)(
))(()()( xx
xf
xxxfxfxf?
′′
+?

+=
)()(
!
)(
0
0
)(
xRxx
n
xf
n
n
n
+?++L 
?
1
0
)1(
)(
)!1(
)(
)(
+
+
+
=
n
n
n
xx
n
f
xR
ξ

ξ
^o? -W¥
?
b
0
x x )(xR
n
?1 ¨
ün
à?[ μ ?ì μ °?
T¥?[
b

H¥
ü à
T?S
X ?

T'0
0
=x
2
!2
)0(
)0()0()( x
f
xffxf
′′
+

+=
1
)1()(
)!1(
)(
!
)0(
+
+
+
+++
n
n
n
n
x
n
f
x
n
f ξ
L
b 
 μ
e
v ? [?
T ¥
ü à
T 1 N
H
o1 pf
)(xf  u W
= μ ¨?

1
),( ba
n

!·° Iù
T? www.tsinghuatutor.com - 32 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
2
0
0
000
)(
!2
)(
))(()()( xx
xf
xxxfxfxf?
′′
+?

+=
nn
n
xxoxx
n
xf
)()(
!
)(
00
0
)(
+?++L 

? 
 ' [?7y μ ?ì μ °?
T?[¥
ü à
Tè¨ ?£
ü??
Ts
Bt ?
ù5b

 μ
e
v?
T?[¥
ü à
Tè¨ ? pK  I° ?
′ù5b 

 μ ?ì μ °?[¥
ü à
T V[
j1 ?ì μ °±s?′? ?¥w<7
?ì μ °±s?′? ?
Lé
^ ¨
ü à
Tb

ó?¥f
é?
ü àZ 7
HB ?μ
?ZE'¨
ü à
T?l p
ò¨ ?
¥ZE ?-1° ¤E 7 ? ¨?f
ü à
T¥ 2
1G  ?¨
f
¥}

Dˉ
é?
ü àZ 7¥ZE d?1W¤ ZEb 5
"? ?
T
àμ+Y·
ü¨°¤ZE5 V ?¨W¤ZEb
è | 
2
)( xxf = 1
0
=x )Z 71B¨
ü à
T μ ?ì μ
°?[
e
v?[
b
3 2)(,2)1(,1)1( =
′′
=

= xfff 
 )¥ Z 7
T1 μ ?ì μ °?[


1
0
=x
22
)1()1(21?+?+= xxx
μ
e
v?[?
T¥Z 7
T1
B¨
))1(()1(21
2
+?+= xoxx b
è  p xxxf?= sin)(  0
0
=x )¥ ?¨
ü à
T μ
e
v?[
b
3o? ?¨ ¥Z 7
Té?
'μxsin

!·° Iù
T? www.tsinghuatutor.com - 33 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
)(
6
1
)(
!3
1
sin
3333
xoxxxoxxx +?=?+?=?
è  p  )¥ ?¨
ü à
T μ
e
v?[?
T
bxtan 0=x
3
1sec)(tan,0tan
0
2
00
==

=
=== xxx
xxx 
0tansecsec2)(tan
00
==
′′
== xx
xxxx
2sec2tansec4)(tan
0
422
0
=+?=
′′′
== xx
xxxx
yN¤? ?¨Z 7
T
 )(
!3
2
tan
33
xoxxx ++= b
è  p  ) μ ?ì μ °?[?
T¥ ¨
ü à
Tb
x
e 1?=x
0
n
3 ¨W¤E | 1
x
e
111
1
+?+
==
xxx
e
e
ee |
j1
 '
7
1+x
e
X
e 1+= xX
 ?¨'Z 7
T'μ
))1(
!
1
)1(
!2
1
)1(1(
1
2
LL ++++++++=
nx
x
n
xx
e
e
n
x
en
x
e
x
ee
)1(
!
1
)1(
!2
1
)1(
11
2
+
+++
+++= L
1
)1(
)!1(
+
+
+
++
n
x
en
e
ξ
L 
 ? ξ D -Wx 1
0
=x ),( +∞?∞∈x b

!·° Iù
T? www.tsinghuatutor.com - 34 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
è 
! 0
)(6sin
lim
3
0
=
+

x
xxfx
x
 p
2
0
)(6
lim
x
xf
x
+

b
3 )()6(
!3
1
66sin
33
xoxxx +?= 
yN?X?Hq
+

3
0
)(6sin
lim
x
xxfx
x
3
33
0
)()(366
lim
x
xxfxoxx
x
++?
=


0036
)(6
lim
2
0
=+?
+
=

x
xf
x

Ka¤? 36
)(6
lim
2
0
=
+

x
xf
x
b
+

3
0
)(6sin
lim
x
xxfx
x
3
0
)(666sin
lim
x
xxfxxx
x
++?
=


3
0
2
0
66sin
lim
)(6
lim
x
xx
x
xf
xx
+
+
=
→→

3
3
0
2
0
)6(
lim
6
1)(6
lim
x
x
x
xf
xx →→
+
= 

!·° Iù
T? www.tsinghuatutor.com - 35 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
Ka¤? 36
)(6
lim
2
0
=
+

x
xf
x
b
?/
TE
^p¥
3
0
3
0
)(6
lim
)(6sin
lim
x
xxfx
x
xxfx
xx
+
=
+
→→

0
)(6
lim
2
0
=
+
=

x
xf
x
p ey?? B??|a ¥í kl
 9D?y 0ê?
dE 9D s? g1
pb


ArE5

A rE5
^ p K¥×1 ZE
^ ? O?′ ? ? üf
1M1  ?
17?¥ZEb
 ? ? 
ArE5
 ?T
 
 0)(lim)(lim == xgxf ∞

 
K??í )(),( xgxf
′′
?i O 0)( ≠

xg  
 

)(
)(
lim
xg
xf


i1í kv 5
)(
)(
lim
xg
xf
i1í k v
O??
)(
)(
lim
xg
xf


b
? 
[
K?¥ t_1
?H∞→
0
xx t_b
  
 h  A ? i  ¨
ArE5
^B?
kV? ??
1′ ?μ K 
5e K ?'μ s? 7? ?
1′ K?i 
ù ? V
i ??
?X?
Hq pNK5
ArE5
k
>??
6ù 
ZE3 %ù5b
è 
 pK

!·° Iù
T? www.tsinghuatutor.com - 36 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
.1
3
cos21
lim
3
0
+

x
x
x
x

3 e
T

3
3
cos2
ln
0
1
lim
x
e
x
x
x
+

2
0
3
cos2
ln
lim
x
x
x
+
=


( )
2
0
3lncos2ln
lim
x
x
x
+
=

()
x
x
x
x
2
sin
cos2
1
lim
0

+
=


.6
1sin
cos2
1
lim
2
1
0
=?
+
=

x
x
x
x

3E e
T
2
0
3
3
cos2
ln
0
3
cos2
ln
lim
1
lim
x
x
x
e
x
x
x
x
+
=
=

+


.
6
1
3
1cos
lim
3
1cos
1ln
lim
2
0
2
0
=
=
+
=
→→
x
x
x
x
xx
?|
5?1

!·° Iù
T? www.tsinghuatutor.com - 37 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
+


1
3
cos2
)1)(cos1(2
1
lim
sin
0
x
x
x
x
ex
5? 5|s
T í kl9D é 7E
°¤¨
A rE5?á ¥ˉ p? 9
b s
??Mb

è  pK
)1(
2sin
2
1
cos1
lim
2
2
2
0


x
x
ex
xxx
b
3
5 I
n?Ní kl}Da I
n
ArE5
)1(
2sin
2
1
cos1
lim
2
2
2
0


x
x
ex
xxx
b
3
1
3
sin
lim
cossin
lim
)cos(sinsin
lim
2
0
3
0
4
0
==
=
=
→→

x
xx
x
xxx
x
xxxx
xx
x

è  pK
ax
ax
ee
axx

ln
lncos
lim b
3
ax
axax
ax
ax
ee
ax
x
ee
axx
=
→→→
ln
ln
limcoslim
ln
lncos
lim

!·° Iù
T? www.tsinghuatutor.com - 38 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
ax
x
ax
ee
e
ax
a
=

1
limcos
ax
ee
ea
ax
ax
x
ax
=


limlimcos
aeae
aa
coscos ==
b
  
e?¥ ??
T
?a
0
0 ∞?∞ ? ?
0
0

1 ?
0
∞ ?

A?YV
a?¥?M?1
0
0



?a?
P¨
ArE5é?
kb
è  pK

xx
x
x
ln
1
1
lim
1
b
3 
ZE 
xx
xxx
xx
x
xx
ln)1(
1ln
lim
ln
1
1
lim
11
+?
=
→→

2
1
11
1
lim
1
ln
ln
lim
2
11
=
+
=
+
=
→→
x
x
x
x
x
x
x
xx
b

ZE 
)11ln()1(
1ln
lim
ln
1
1
lim
11
+?
+?
=
→→
xx
xxx
xx
x
xx


!·° Iù
T? www.tsinghuatutor.com - 39 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
2
1
)1(
1ln
lim
+?
=

x
xxx
x
2
1
)1(2
1
lim
)1(2
ln
lim
11
=
=
=
→→
x
x
x
x
xx
b
8 è5
è 
! =¨ V? O)(xf 0
)(
≠+
x
xf
x X?
,)
)(
1(lim
3
1
0x
e
x
xf
x
x
=++


p )0(),0(),0( fff
′′′
b
s? 4)0(,0)0()0( =
′′
=

= fff 
<3>?5¤
3
)
)(
1ln(
1
0
1
0
lim)
)(
1(lim ee
x
xf
x
x
xf
x
x
x
x
x
==++
++
→→
é7¤
3
)
)(
1ln(
lim
0
=
++
→ x
x
xf
x
x
0)
)(
(lim0)
)(
1ln(lim
00
=+?=++?
→→ x
xf
x
x
xf
x
xx
yN

!·° Iù
T? www.tsinghuatutor.com - 40 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
x
x
xf
x
x
)
)(
1ln(
lim
0
++

3
)(
lim
0
=
+
=
→ x
x
xf
x
x
' 3
)(
lim
2
2
0
=
+

x
xfx
x

3
)(
lim1
)(
lim
2
0
2
2
0
=+=
+
→→
x
xf
x
xfx
xx

[ 2
)(
lim
2
0
=

x
xf
x
 O 2
2
)(
lim
0
=


x
xf
x

? ???D?
?l¤?
4)0('',0)0(',0)0( === fff b
 0)0(),(2)(
22
=+= fxoxxf#
4)0('',0)0(' == ff b
è 
! )(xf  0=x

#×
= V? O
2)0(,1)0( =

= ff 
pK
∞→
n
f
n
n
n
n
1
1
1
sinlim b
3 I
nK
()()xfx
x
x
x

1
1
0
sin
1
lim 
))(1(
sin
sin
0
2
sin
1lim
xfx
xx
xx
x
x
x
xx?

+=

!·° Iù
T? www.tsinghuatutor.com - 41 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
??K? ?o3 pK
))(1(
6
1
lim
))(1(
sin
lim
2
3
0
2
0
xfx
x
xfx
xx
xx
=
→→
12
1
)0(6
1
)(1
lim
6
1
0
=

=
=
→ fxf
x
x

?i[
? ???|
^¨
K?lb
 ?ˉK? ?¤?
()()
12
1
1
1
0
sin
1
lim ex
x
xfx
x
=

yN
12
1
1
1
1
sinlim e
n
n
n
f
n
n
=
∞→
b
? h +Y?i?=? ?|a¥ K9
 ?

Ar E5 y1 ?
1′
¥KíE p¤ '5
àμ ??¥Hq
b)(xf ′
 '/
TE
^p¥
12
1
)0(6
1
)(
1
lim
6
1
)(1
lim
6
1
00
=

=

=
→→
fxfxf
x
xx
[
? ???|¨?
 )(xf

¥ ???7'5?ó )(xf

¥ ???H
qKíE9
2Tb?
^¨
ArE5
H¥ènpb
è 
! )(xf  =¨ V? B M),0[ ∞+ ),0( ∞+∈x μ
0)( ≠
′′
xf £
ü ),0( ∞+
= wL )(xfy = 
B?
))(,(
00
xfx )¥ MLD? wL" M??í??b
<£>
ZE 5BZMPS
TZEb|
ZE ?¥

!·° Iù
T? www.tsinghuatutor.com - 42 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
)()()( xyxfxF?=
))(()()(
000
xxxfxfxf?

= 
 )Z 71 5BZMPS
T
0
xx=
,))((
2
1
)(
2
0
xxfxF?
′′
= ξ ξ -Wb
0
xxD
y1 0)( ≠
′′
xf ??
,?? ?  )(xf
′′
?M| 5 g
?M|b£8b
)(xF
è 
! £
ü b4
U
!,eab >>
ab
ba >
xaaxxf lnln)(?= 
x
x
xf
ln
)( = b
<£>/ ex
x
x
xf >= ?
ln
)( 5
2
ln1
)('
x
x
xf
= ^¤ 0)(' <xf 
[ )(xf
^?ì?h ¥ μ,eab >>
)()( afbf < '
a
a
b
b lnln
< ??¤
ba
ababba lnln,lnln << ' 
?
f
¥?é¤ b
ab
ba >

è X?f
μ=¨ ???
)(xf 0)1()0( == ff b£
ü
?
H]1,0[∈x

!·° Iù
T? www.tsinghuatutor.com - 43 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
})({max
2
1
)(
]1,0[
xfxf
x
′′



b
£
ü |]1,0[∈?a )(xf  ax = )Z 71
() () ( ) ()( )
2
2
1
)( axfaxafafxf?
′′
+?

+= ξ

ξ -Wxa,
sY
7 ¤?1=x 0=x
() () ( ) ()( )
2
1
1
2
1
1)(10 afaafaff?
′′
+?

+== ξ
? )1,(
1
a∈ξ 
() () ( ) ()()
2
2
2
1
)(00 afaafaff ξ
′′
+?

+==
? ),0(
2
a∈ξ 

TMhiM[? ?
()( ) ()( )
2
2
2
1
1
2
1
)( afafaf ξξ
′′

′′
=


? 
H0=a 1=a ()
1
2
1
)( ξfaf
′′
=


()
2
2
1
)( ξfaf
′′
=

e??
T¥?|? ?b
?
H? ????
T¤?)1,0(∈a
()() ()
2
2
2
1
1
2
1
)( afafaf ξξ
′′
+?
′′



7 ( ) ( ){ }
21
,max)( ξξξ fff
′′′′
=
′′


!·° Iù
T? www.tsinghuatutor.com - 44 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
? )1,0(∈ξ byN
()() ()ξξ faafaf
′′
≤+?
′′


2
1
1
2
1
)(
22
})({max
2
1
]1,0[
xf
x
′′


b
?
^
 ?iB?a ]1,0[
[ })({max
2
1
)(
]1,0[
xfxf
x
′′



b
è 
! )(,0 xf>δ  uW ),( δδ?
=μ?l
 ??
),( δδ?∈x
H
μ
2
)( xxf ≤

5 A
^0=x )(xf ¥<$>b
"
W?b #
 ??7? V?¥?b
$
 V?¥?
 O 0)0( =

f b
%
 V?¥?
? 0)0( ≠

f b
}3~? ),( δδ?∈x
Hy1 
2
)( xxf ≤ 
7  0=x ¤?
0)0( =f b
6?μ x
x
xf
≤≤
)(
0 

[
?C/5¤ 0
)(
lim
0
=

x
xf
x

O )0(0)(
lim
0
fxf
x
==

b

!·° Iù
T? www.tsinghuatutor.com - 45 - bvD ? S
L 1101 è 62781785
2005

!·°
TDn bê
ê?7<v0 1006 bvD ? S
L 1101 è 62781785
6??μ,
)(
x
x
xf
x ≤≤? Q?C/5¤
)0(0
0
)0()(
lim
)(
lim
00
f
x
fxf
x
xf
xx

==
=
→→

[s?1
$ b


!·° Iù
T? www.tsinghuatutor.com - 46 - bvD ? S
L 1101 è 62781785