Ôn tập kinh tế vi mô

Thu Luu 
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

 

:
 
 và có  mua 


* Nhu 







- 
-  (I)
-  hóa có liên quan (P
y
)
-  (Tas)
- 
- (N)
 
(P và Q )
- 
- 


- 


- 





- Q
X
= f(P
X
)
Q
X
 
P
X
 giá hàng X
: 

Giá ($/kg)

3,5
3,0

2

4





bán  và có 
 

 (cung)

(cung)
(cung) là 1 

 (cung) 
 (NSX)

- 
- 
- Giá hàng hóa có liên quan
- P 
- 


(P và Q 
- 
- 

 
- 

- 





- Q
X
= g(P
X
)
Q
X
 hàng X
P
X
 giá hàng X
: 

Giá ($/kg)
cung
3,5
3,0

9
7,5

Thu Luu 

- 2 -
III. 






-  
-  








Hình:

1
  
 


2


- 
         





Hình:

  




-          


         



- 
,QP

- 
,QP

- 
,QP


P
E


Q
E


Khi:
- P
1
> P
E

- P
2
< P
E
 
Thu Luu 
- 3 -

1.  


- 
-        
hình thành quá cao
- 


 và ch.lg)















       


  :





- cao 
-        
hình thành quá 
-  







Q

= L
s
 L
D















 


n



Thu Luu 
- 4 -
2. Can :
a. 






Q
1
< Q
0

P
1
> P
0
P
1
 P
2




P
0

: 
P
1
: P
td

P
2
: P
sx


(P
0
,P
1

(P
2
,P
0
g
(P
0
,P
1
) + (P
2
,P
0



Q
D
= 150  50P (1) Q
S
= 60 + 40P (2)
a. 
b. 
c. 
d. 

a.  
=> Q
S
= Q
D

 150  50P = 60 + 40P
=> P
0
= 1 => Q
0
= 100
b. )
=>
1
60
0,5
40

b
S
Q
P


=>
1
40 40
b
S
QP
(*)

b
SD
QQ
=> 40P1 + 40 = 150  50P1 => 90P1 = 110 => P1 = 1,22 $
b
SD
QQ
= 150  50 x 1,22 
c. 
d. : (P1,P0) = 0,22 (P0,P2) = 0,28 (Q1,Q0)=11
()
2
Daylon daybe
CS A B cao

     

= 
01
10
()
2
QQ
PP



 
()
2
Daylon daybe
PS D C cao

     
= 
01
02
()
2
QQ
PP


=  26,46
 
G A D   
 $

 
()WL B C    
1
2

1
2
0,5 x
P
0

P
1
: P
td

P
2
: P
sx

- ( A+B) => 
- (D+C) => 
 => 
= -(B + C)=> t

Thu Luu 
- 5 -



























Thu Luu 
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- CUNG




(E
D
)
2. 
(E
I
)

(E
xy
)
cung theo giá
(E
S
)

% bi    
P 

%
%
.0
D
D
Q
Q
Q
E
P
P

P
QP
E
PQ









* 
D

- Luôn luôn âm - Ko
- 
P
tg
Q





=>
1
.
D

P
E
tg Q



 







     
      thu

%
%
.0
I
D
Q
Q
Q
E
I
I
I
QI

E
IQ















b. 
a:
 theo
      

x
%
.
%
y
xx
xy
yy

P
QQ
E
P P Q













b. 

     


%
%
.0
S
S
Q
Q
Q

E
P
I
P
QP
E
PQ











D
,E
S
)







Thu Luu 

- 7 -
(tt)

D















1 % %
D
E Q P    



1 % %
D
E Q P    


1 % %
D
E Q P    

 
TR = P x Q
d. 
- 
- 
- 
Thu Luu 
- 8 -
II: 
TIÊU DÙNG
I. LÝ 



 


  TU     
khi tiêu dù 
, trong 


Là  iêu dùng
 

MU =
TU
Q



Q = 1 thì ( sp là liê

11n n n
MU TU TU




       

2. 
- 
- 
- 

3. 
- 
các cá nhân.
4. 


        
 cho
 khi







- 


Thu Luu 
- 9 -
II. 
1. 
a. :
- 
A >>B; B>>C => A>>C
- 
- 
b.  





 
Tỷ lệ thay thế biên giữa 2 sản phẩm X và Y
là số lượng sản phẩm Y mà người tiêu dùng
sẵn sàng từ bỏ để có thêm 1 đơn vò X.
MRS =
Y

X





- 

- 
RS 
- 
UxMY
MUy X






∆TU = MU
X
.∆X + MU
Y
.∆Y = 0
MU
X
/MU
Y
= - ∆Y/∆X = MRS


- 
- Hàng hóa hồn t      

          

P
x
.X + P
y
.Y = M

x
yy
P
M
YX
PP
  





x

()
y
P
P









 
 khi mua X








 
- MRS =

xPY
Py X


Thu Luu 
- 10 -


U
3

U
1

U
2


- 

x
y
P
Y
XP




=>
x
RS=
X
Y

MU
PY
M
Py X MU

  











x
RS
X
Y
MU
P
M
Py MU

hay
xy

y

n
X
n
MU
MU
MU
P P P
  


Và XP
x
+ YP
y
= M
Thu Luu 
- 11 -
V: LÝ 

:
1:
  
 


-  

-  



-   .
-   

2. 


 ):
Q=f(K,L) K 
 

- 
L
Q
AP
L


- 


L
Q
MP
L




L = 1 => MP
L

= Q
n
 Q
n-1


Thu Luu 
- 12 -
- 




 Giai 
1
) : MP
L
> AP
L
=> AP
L
 , Q 

do chuyên môn hóa và phân công hóa)
 
1
,L
2
) : MP
L

< AP
L
=> AP
L
 , Q 

 
2
): MP
L
> AP
L
=> AP
L
, Q 


 (Thomas Malthus)




Q=f(K,L)
 
KL
KL
KL
MP MP
PP
KP LP TC





  

 
- 
- 

- Không 
 :

 
RS
LK
K
MT
L




 
. . 0
RS
LK
L
K
Q MP L MP K

MP
K
MT
MP L
     

  


K
(MP
L

Thu Luu 
- 13 -



LK
LP KP TC

+ 
L
KK
P
TC
KL
PP
  

+ 
L
K
P
K dK
tg
L dL P


   








-    
   
   
E
-   

 
- 
RS
L
K
LL

KK
P
K
LP
P MP
K
MT
P L MP




    


Hay

n
LK
L K n
MP
MP MP
P P P
  

-  
RS
L
K
LL
KK
P
K
LP
P MP
K
MT
P L MP




    


Hay

n
LK
L K n
MP
MP MP

P P P
  




- 

 

Thu Luu 
- 14 -


0
, L
0

0


K
1
=2K
0
, L
1
=2L
0


1

 
1
> 2Q
0

 
1
< 2Q
0

 
1
= 2Q
0









%
%
Q
K







)

%
%
Q
L






)


1.
1
Q K K




2.
32KL

Ta có: Q = 3K + 2L
=> 2Q = 6K + 4L = Q
1

=> Q
1



 DOUGLAS
Q aL K



1



1



1



Thu Luu 
- 15 -



-  
- 

 
Pr k toán = TR  
 

 
 
 
 

TC(T)FC
(T)VC
MC
Các hàm chi phí trung bình
AFC, AVC, AC)

Q
FC
VC
TC
MC
0
30
0
30

1
30

22
52
22
2
30
38
68
16
3
30
48
78
10
n
in
i
MC VC



     



    

(các YTSX NL, ld)








    



TC VC
MC
QQ





Khi
1Q

1 1 1n n n n
MC TC TC VC VC
  
   

Q
AFC
AVC
AC
MC
0
-
-
-

1
30
22
52
22
2
15
19
34
16
3
10
16
26
10


AF
FC
C

Q



VC
AVC
Q



AF
TC
AC C AVC
Q
  









Ghi chú:      
       
        





(Q=0 => CP =TFC)


Thu Luu 
- 16 -



MC và MP
L
& AVC và AP
L


MC < AC  AC 
MC > AC  AC 
MC = AC  AC min









MC = AC
 0

MC < AVC  AVC 
MC > AVC  AVC 
MC = AVC  AVC min
1
L
L
PL
VC
MC P
Q
QQ
L


  





L
L
P
MC
MP



L
L

P
AVC
AP


Hay:
AP
max
 AVC
min

MC
max
 MP
min












Thu Luu 
- 17 -


























Thu Luu 
- 18 -
 + VI: TT CTHH  
 (CTHH)

I. 

      
        
       
, 
, 

 
1
 

 

 
 Các doan


- 
TR=P.Q (P=.th  O)
- 
- 
- 
.
AR
TR P Q
P
QQ
  


       









I. 
      
h





:
     


      

+ Nguyên nhân pháp lý
 



       


 0 < Q < Q
M
;MR>0

P



Q



D
E
>1
 Q
M
< Q < Q
A
;MR<0

P



Q




D
E
<1
 Q= Q
M
; MR=0


D
E
=1

TR
max


Thu Luu 
- 19 -

        

MR
Q
= TR
Q
 TR
Q-1

=
TR
Q



Trong TT.CTHH. MR = P = AR

II. 

-       




)
Pr = (P  AC) Q
Doanh n sx q
0

0
và thu

0
-AC
0
).q
0


D

D
1
R (1 )MP
E


D
< 0
Hay
D
1

R (1 )MP
E


=> MR luôn luôn < P

II. 
1. M

)

:
















Thu Luu 
- 20 -

:
P = P
1

1

: TP = (P1  AC
1
).q
1









P = P
2
= AC
min

TR
2
= TC
2







P = P
3
, AVC
min
< P
3
< AC
min

P = P4 = AVC
min

















(2) =>
 
0,
EM
QQ
 
          

(3) 

P = AC + a. AC

(AC: Cphí bình quân 1 sp, a
(4) Doanh ngh
5-      








6-        











Thu Luu 
- 21 -
 

- 

P > AVC


P < AVC 
- à MR


MC = MR = P
=> TR = P.Q TVC = Q. AVC= Q.P
L
min


















- 
(MR = MC)
- :

1
R (1 )
D
MP
E


=>
D
D
()
1
E
P MC
E



- 
1
D
L
E

(E
D
<0)
 



      
D
chí  

+ Q )
Các chi nhánh Q
1
Q
2

MC
1
MC
2

=> Q
1
, Q
2

    

MC = MR = 0

       

MC
1
= MC
2

= … = MR
Q
1
+ Q
2
+ …+ Q
n
= Q
E










>