《微观经济学?高鸿业第四版)第三章练习题参考答?- 百度文库 ر

΢۾ѧߺҵİ棩ϰο

1֪һļ۸Ϊ80Ԫһݿϵ¼͵ļ۸Ϊ20Ԫij߹ƷЧ󻯵ľϣһݿϵ¼ͶԳı߼MRSǶ٣

⣺Ʒı߼MRSĶ幫ʽ,Խһݿϵ¼ͶԳı߼д: MRSXY???Y?X

:Xʾϵ¼͵ķ;Yʾļ; MRSxyʾάЧˮƽǰ, һݿϵ¼ʱҪij

ڸʵֹƷЧʱھ MRSxy =Px/Py

MRSxy =20/80=0.25

Ч󻯵ľϣ߹һݿϵ¼ͶԳı߼MRSΪ0.25

2 ijߵľͼ1-9ʾУOX1OX2ֱʾƷ1Ʒ2߶ABΪߵԤߣUΪߵ޲ߣEΪЧ󻯵ľ㡣֪Ʒ1ļ۸P1=2Ԫ

1ߵ룻 (2)Ʒ2ļ۸P2 (3)дԤߵķ̣ (4)Ԥߵбʣ (5)EMRS12ֵ

⣺1ͼеĺؾʾߵȫƷ1Ϊ30λ֪P1=2ԪԣߵM=2Ԫ30=60Ԫ

2ͼеݽؾʾߵȫƷ2Ϊ20λɣ1֪M=60ԪԣƷ2ļ۸P2=M/20=60/20=3Ԫ

3ԤߵһʽΪ

P1X1+P2X2=M

ԣɣ12ɽԤ߷̾дΪ2X1+3X2=60

43еԤ߷̽һΪX2=-2/3 X1+20ԤߵбΪ2/3

5Ч󻯵ľEϣMRS12=P1/P2޲ߵбʵľֵMRSԤߵбʾֵP1/P2ˣڴMRS12=P1/P2 = 2/3

X2 A B U 20 E 10 O 10 20 X1 30

3 뻭¸λ߶ƷȺȲ裩޲ߣͬʱԣ2ͣ3ֱдBCЧú

1AϲȿȣԺȲνϲи౭ĿȣӲжٱȲ衣

2BϲһȺһȲһȣϲֻȿȣߵֻȲ衣

3CΪκ£1Ⱥ2Ȳ޲ġ 4DϲȲ裬ȿȡ

𣺣1⣬AԣȲƷˣȲӰAЧˮƽA޲߼ͼ

2⣬BԣȺȲȫƷЧúU=min{ X1X2}B޲߼ͼ

3⣬CԣȺȲȫƷЧúU=2 X1+ X2C޲߼ͼ

4⣬DԣƷD޲߼ͼ

4֪ijÿƷ1͵Ʒ2Ϊ540ԪƷļ۸ֱΪP1=20

ԪP2=30ԪߵЧúΪU?3X1X22ÿ깺ƷӦǶ٣ÿлõЧǶ٣ ⣺ߵЧ󻯵ľ MU1/MU2=P1/P2

УU?3X1X22ɵã

MU1=dTU/dX1 =3X22 MU2=dTU/dX2 =6X1X2 ǣУ

3X22/6X1X2 = 20/30

X2=4/3X1 (1)

1ʽԤԼ20X1+30X2=540ã X1=9X2=12

ˣÿ깺ƷӦΪU=3X1X22=3888

d5ijƷгֻABߣǵΪQA?20?4PdQB?30?5P

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