39.A2019-20201

BC1

10

5

50

B

C.

D

2

，

D

A

A

B

B

C.

D

4.

5

A0

B

C

D4

C.2

D

6

A

B

C.

D

7.

8.

A1

A

B2

C3

C.

D4

El

B

D

，，-

，

，

A

B

C

D2

10.

1

M

C

x

:N__________

O

AKBio

y

y

y

y

5

25

?

5

y—

11.

12

S=s+i*im*1

n

i=0,S~1

A

13.

S-ABCSAAB=AC=2

.ASB=/BSC=/CSA=30

'MC

MN

SBSC

AMN

.

，，

14.

15.

.

6

75

16.

12

（1

(2

.

17.

12

AOB,

AOB

2

OA

C,

C

0B

ABP.

1

2

C

,

0A

PC

.

18.

12

60

.

15

5

2

6

4

2

1

(1)

(2)

60

10

2

6

19.

20.

12

(1)

(2)

1/

13

C

10

C

Q40

A1

I

CAB

A

x

"Bx

21

14

+x

2

+bx+cx<1

—X’

f(x)

alnx,x1

?

(1)

(2)

(3)

xx

15BCDDA

11.1012.1113.

610BBCCA

14.15.

16.

(1

d

2(log22d)=log22log28

d=1

log2(an-1)=1(n-1)1=n

1

n1

2_2n

(2

11

an1

------x—

22

n

__11-

2

=2_

A…12

2n

17.:(1)

OP—C3

PCcos

(2

CPOPOB

3

2

CP

.2

sinr

sin-3

OP

OC

2

n

sin-

sin()

3

i0)=si

co

4sin4s

23

3

12

10：1

18.

10

6

2

6

)

)

)

a2,(a1,a1,a4,(a1,b),(a1,b2

2,a32,2,bl2,

b

2

(a

),(a

a

4

),(a

),(a

10

12

19.

1

2

................................................9

CM=VDCM=VMJDAC

??VS

1C1CA111

32=322=12

1

Vs

=S

SA

...............12

CM

ACD

20.

(I)

(LM

C=l.

2

1

2

a

T

4=2

1,24

3

(2

(3m224)y24my36=0.

8

t=

)

(4my2y(4myjy?

1

A

yy2

.

X2%y2

yy

1

2

10

3

21

(1

2

-3(-1)

2(-1)b5,b=0

3

f(x)-xx,f(x)-3x22x

32

(2)

，

6

(3)

①

OP_OQ,

=_1

x-i-x1

(i)

7

(

(ii)fXJ-xj,f(-Xj

-xj

i0

Xi

Xi

32

Xi

_i

X

(iv)

(iii)

f(Xi)

i

aIn

-

XI

=-i

(xi)lnxi

i

a

X

xii

g(x)i=(Xi)lnx(xi)=g(xj=Inxi

ii

0

X

i

i

I=■

aln(xd-Xi3

i

=(-Xii)ln(-Xi)a

—

—Xi

Xi

XiXi

——i,(—X

2

3

2

3

2

2

(

Xi)M

X1

Xi)=Xi

i

h(xj=(—Xi?i)ln(—x)(xii：：：—i)

.

i2

i4

20i9-2020

i2

5

6

30

？

16

xx

4s

A

?-

B

2s

?-

C

2s

2s

Dt=4s

AB

B

A

C

2s

2s

4

C

D

B

？

26

xx

1

40

F

t

2

g

I

2

Ag

B2g

C3g

|D4g

O.6Fo

1.8Fo

1.8Fo

O.6Fo

O.6Fo=mg

Fm=1.8F0

Fmg=ma

1.8Fomg=mam

am=2g

Ft

36

xx?

M

R

g

G

A

C

3=

B.

v=

T=2n

D.

a=

A

A

B

C

D

v=B

C

D

A

？

4.6

xx

Ac

b

B.a

C.

b

+qa

b

D.

d

Q

+qa

b

A

b

b

A

B

C

a

b

B

+qa

a

C

D

+qa

D

B

？

5.6

mo

xx

M

v

m

A

B.

C.

vi

M+mvi

D

vi

V2

M+mov=M+mov+mvi2

Mv=

M+m

C

ABD

C

5

68

6.12xx?

U

f

5ABCDE

m

A

0

AC

siCE

S2

gU

0

C

Ep=mgs+s

o1

△

Ek=_______

g=_

Ep=mgh

h

vn=

△

C

Ek

x-aT

i

△

Ep-mgs+s

oi

C

v-cT-

△

Ek--2s2

s-ai

2

a-

g

mgs+s

oi

△

T-

x-aT2

T

？

7.7xx

I

o

n

mi

B

m2

mi

mim2

CA

W

A

A

mim2

mim2

mim2

hi

h2h3

=+

1A

mim2

mim2A

B

C

B

CD

2

h=gt

t=v==x

m1vm1v2+m2v3m1x=m1x+m2x=+

1A

2=+

？

&15xx

m=1kg

1m

F

F=4N

V=2m/s

F

F2s

S

1

2ax=v2

2

a=2m/s

0.2

F

f

F!img=ma

2

f=ma2

a2=2m/s2

0

v2s

0-V2=2a2X

1

0.2

2

F2s

S1m

？

9.16xx

I

E

m

E

1

qE=mg?tanB

:

-----------------

(mg+qE)?!(1-cos6)

?

i1-'-n1-

11■1:

-----------------------------------------------------------

/

1

■

-------------------------------------------------------------Jfa.

*

E

I

？

10.18(xx

mi=2

1

37

ABA

2

0.2

BCBC

C

m2=1

2

D

R=0.4

2

2

g10m/ssin37°=0.6cos370.8

12

AB

2

2

BC

1

2

1

C

AB

h

1

A

B

12

2D

12

1

1

1

1

B

12

D

m2g=m2

vD=2m/s

2

2

2

BC

2R=gt

x=VDt

v

x=0.8mBC

2

BC

2CD

22

m2vc=m2g?2R+m2VD

vc=2m/s

12

1

m1V1=m1V1'+m2vc

mv12=m1v12+m2vc2

v1=m/sv=m/s

1

(

1

m1gs=0m1v12

v

s=mm=BC

1

C

m

1BC

22

g1g?BC=m1v1m^B

vB=4m/s

1AB

m1gh=m1vB2

h=0.8m

2

a==gsin3710>0.6=6m/s

1AB

(1

t==s=s

2

2m/s

2

BC

A

1

2

1

C

m

AB

h0.8m

1

B

s

10

11

12

10

3-3

11.6