Phuong Phap Giai Mot So Bai Tap Kinh Te Vi Mo

7/30/2019 Phuong Phap Giai Mot So Bai Tap Kinh Te Vi Mo

1/23

Hm cu v hm s cung ca mt sn phm c cho di ycu: P=-1/2Q+100; cung: P=Q+10 (P: ng, Q:kg)1.Hy tm im cn bng ca th trng2.Hy tnh co gin ca cung v cu theo gi ti im cn bng cu th trng3.Hy tnh thng d sn xut, thng d tiu dng, thng d ton x hi. Gi s

chnh ph nh thu 5ng/vsp.Tn tht x hi do thu gy ra l bao nhiu? v saoli c khon tn tht ?4.Nu nh nc p t mc gi trn cho sn phm l 50 ng, hy tnh khon tntht v ch ca phc li x hi v hy gii thch ti sao li c khoan tn tht ny?

a) Ti im cn bng: PE=PS=PD, QE=QS=QD=> Gii pt cung cu c: PE=70 VQE=60b) Ed= Q'd*P/Q= - 2,33, Es= Q's*P/Q= 1,167c) v hnh ra c : CS= 900, PS=1800=> NSB=CS+PS=2700G/S CP nh thu vo ngi sn xut l : t= 5=> PS=Q+15im cn bng mi: PE'=71.67, QE'=56,67

Gi m ngi tiu dng phi tr: PD= Gi cn bng sau thu= 71,67Gi m ngi sn xut phi tr: PS= 71,67- T=66,67CS=802,73, PS= 1605,74=> NSB= 2408,47Phn mt khng l: 291,53d)PC= 50 => QD=100,QS=40=> DWL= 300

Khi chnh ph nh thu ngn ng/ sn phm th gnh nng thu kha ny ai lngi phi gnh chu? C th l bao nhiu?

Khi chnh ph nh thu thng thng c nh sn xut ln ngi tiu dng u phi chu

thuTheo cng thc nh sn xut phi chu 1 khon thu bng (Ed*t)/(Es-Ed) cn ngi tiudng chu (Es*t)/(Es-Ed) . Do vy khi Ed>Es th ngi sn xut phi chu phn ln thuv ngc li khi Es>Ed th gnh nng thu dn vo ngi tiu dngKhi Ed=Es th thu c phn b u cho c hai bnNgoi ra khi Ep


2/23

g. Khi mc gi trn th trng l 30$ th hng c tip tc sn xut ko v sn lng lbao nhiu?

a.FC = 169

VC = TC FC = Q2

+ QAVC = TC/Q = Q + 1 + 169/QMC = (TC) = 2Q + 1b. Khi P = 55 $DDK ti a ho li nhun P = MC => 55 = 2Q + 1 => Q = 27Li nhun ti a:TR TC = 55*27 (272 + 27 + 169) = 560c. Hng ho vn khi P = ATC minATC = Q + 1 +169/QATCmin khi (ATC) = 0Q = 13

d. Hng ng ca sn xut khi: P = AVCminAVC = Q + 1 => AVCmin = 1Vy khi P = 1 hng ng ca sn xute. ng cung ca hng l ng MC bt du t im P > AVCminP = 2Q + 1 (vi P > 1)f. Nu Chnh Ph nh thu 5$/n v sn phm khi :TC = Q2+ Q + 169 + 5Q = Q2 + 6Q + 169MC = 2Q + 6AVCmin = 6, hng ng ca sn xut khi P = 6ng cung ca hng P = 2Q + 6g. Khi mc gi trn th trng P = 30 $ATCmin = 27, ta thy ATCmin > Phng tip tc sn xutSn lng khi : Q = 14.5

1 doanh nghip trong thj trng cnh tranh hon ho c hm AVC = 2Q + 10 trongdo AVC n v l USD . Q l n v 1000 sn phm.a) Vit phng trnh biu din ng cung ca doanh nghipb) Khi gia bn ca sn phm la 22 USD th doanh nghip ha vn . Tnh chi ph cnh ca doanh nghip nu doanh nghip tit kim c 1000 usd chi ph c nhth li nhun ca doanh nghip l bao nhiuc) Nu chnh ph tr cp 2 usd trn mt n v sn phm bn ra th doanh nghips la chn mc sn lng no tnh li nhun thu c

a. Ta c:VC = AVC.Q = 2Q2 + 10QMC = (VC)' = 4Q + 10Do y l doanh nghip cnh tranh hon ho => Ps= MC = 4Q + 10.


3/23

Vy ng cung ca doanh nghip c phng trnh l Ps = 4Q + 10.

b. Doanh nghip ha vn =>> TR = TC P.Q = VC + FC. 22.Q = 2Q2 + 10Q + FC FC = 12Q - 2Q2

T cu a, ta c Ps = 4Q + 10 => Q = (P - 10)/4 = (22 - 10)/4 = 3Thay Q = 3 vo ta c:FC = 12.3 - 2.32 = 18 (nghn USD)

Ta c: TC = VC + FC = 2Q2 + 10Q + 18Li nhun doanh nghip thu c:TP = TR - TC = P.Q - (2Q2 + 10Q + 18) (1)Khi doanh nghip tit kim c 1000USD chi ph c nh:TP = TR - TC2 = P.Q - (2Q2 + 10Q + 17) (2)T (1) v (2) suy ra, khi doanh nghip tit kim c 1000USD chi ph c nh th linhun ca doanh nghip s tng thm 1000USD. Trc khi tit kim, doanh nghip ha

vn, vy sau khi tit kim, tng doanh thu ca doanh nghip l 1000USD.c. Khi chnh ph tr cp cho doanh nghip 2$/ 1 sn phm:MCe = MC - e = 4Q + 10 - 2=> MCe = 4Q + 8.Trc khi c tr cp th doanh nghip ang ha vn. La chn sn xut ca doanh nghiplun nhm ti a ha li nhun, do :P = MCe => 22 = 4Q + 8 => Q = 3,5 (nghn sn phm)Li nhun m doanh nghip thu c:TP = TR - TC = P.Q - (2Q2 + 10Q + 18 - 2Q)= 22.3,5- (2.3,52 + 10.35 + 18 - 2.3,5) = 6,5 (nghn $)

Mt ngi tiu dng c hm li ch : U = 1/2 X.Y v ng ta c khon thu nhp 480$. mua X, Y vi Px = 1$, Py= 3$.a. ti a ho li nhun vi thu nhp cho, ng ta s mua bao nhiu sn phmX? bao nhiu Y?. Tnh li ch thu cb. Gi nh thu nhp ng ta gim ch cn 360$, kt hp X, Y c mua l bao nhiu li ch ti a. Tm li ch .c. Gi nh rng gi ca Y khng i, gi X tng thm 50% th k hp X, Y cchn l bao nhiu li ch ti a ho vi I = 360$.

a, Ta c:I=X.Px+Y.Py =>480=1X+3Y (1)ng thi th iu kin ti a ha li nhunh th:(MUx/Px)=(MUy/Py) =>(0,5Y/1)=(0,5X/3) (2)T (1) v(2) ta c: X=210 v Y=80Li ch l:TU=0,5.210.80=8400b, Khi thu nhp gim cn 360 th360=1X+3Y (1'')T (1'') v (2) ta c h pt =>Gii ra ta c tng tc, V gi hng ha X tng ln 50% nn Px''=1,5


4/23

H pt: 360=1,5X+3Yv (0,5Y/1,5)=(0,5X/3)Suy ra X=120 ,Y=60

1 doanh nghip cnh tranh hon ho c hm chi ph bin i bnh qun: AVC

=2Q+4 (USD)a, Vit phng trnh biu din chi ph bin v xc nh mc gi m doanh nghipphi ng ca sn xut.b, Khi P= 24 USD th doanh nghip b l 150 USD. Tm mc gi v sn lng havn.c, Doanh nghip sn xut bao nhiu sn phm ti a ha li nhun nu gi bnP= 84 USDTnh Q ti u? li nhun max?

a, Theo ra ta c:AVC=2Q+4 suy ra MC=VC'(Q)=TC'(Q)vi VC=AVC*Q=2Q^2+4Q ==> MC=4Q+4

Mt khc y l th trng cnh tranh hon ho nn Ps=4Q+4 (Q>0)Doanh nghip ng ca sn xut khi P=AVCmin vi AVCmin=4 ==> P=4b, Khi P=24 doanh nghip thua l 150 do ta s thy l :TR-TC=-150==> 24*Q-(2Q^2+4Q)-FC=-150 ==>FC=20Q-2Q^2+150 (1)M khi p=24 th Q=(24-4)/4=5 thay vo 1 ta c FC=200Nh vy th TC=VC+FC= 2Q^2+4Q+200 (2)=>ATC=2Q+4+200/QKhi doanh nghip ha vn th P=ATCminvi ATCmin ATC'=0 2-(200/Q^2) =0 =>Q=10Thay vo Ps ta c: P= (4*10)+4=44c, Vi gi P=84 th doanh nghip ti a ha li nhun khi P*=MC=> 84=4Q+4=> Q*=20TPmax= 20*84- 2*20^2+4*20+200=1680-1080=6001doanh nghip c hm s cu :P= 16-Q+24/Q ;v TC = 43+4Qa. Hy vit hm s chi ph bin, doanh thu, chi ph bin, chi ph bin i, li nhunb. Hy xc nh sn lng, tng doanh thu, tng li nhun, gi th trng trong cctrng hp :+ Khi DN theo ui mc tiu ti a ha li nhun+ Khi DN theo ui mc tiu ti a ha s lng bn vi iu kin khng l+ Khi DN theo ui mc tiu ti a ha doanh thu khng km theo iu kin rngbuc+ Khi DN theo ui mc tiu tng li nhun =16+ Khi DN theo ui mc tiu t li nhun nh mc trn chi ph bnh qun 20%

a/ MC=(TC)'=4TR=P*Q=Q*(16-Q+24/Q)=16Q-Q^2+24Khi Q=0 th FC=TC=43=> VC=TC-FC=4Q


5/23

LN=TR-TC=12Q-Q^2-19b/+. LN max MC=MR => 4=16-2Q => Q=6,P=14 => TR=84, TC=67, LN=17+. LN>=0 12Q-Q^2-19>=0 => 1,8P=8.4 ,TR=84 ,LN=1TR max TR'=0 =>16-2Q=0 =>Q=8,P=11,TR=88,LN=13

+. LN=16 12Q-Q^2-19=16 => '+ Q=5=>P=15.8,TR=79'+ Q=7 =>P=12.43,TR=87=. LN=120%TC/Q 12Q-Q^2-19=1,2*(43/Q+4) => + Q=8.5=>P=4.67,TR=87.75,LN=10.75+ Q=4.8=>P=16.2, TR=77.76,LN=15.56

Xt th trng cnh tranh hon ho. Hm s cu v hm s cung nh sau:Qd =3280 - 8pQs = 282 + 2pa/ Xc nh sn lng v gi c cn bng. Tnh h s co gin gia cu v cung tithi im cn bng. Nu chnh ph nh thu sn lng th ai chu thu nhiu hn?

ti sao ?b/ Chnh ph nh thu sn lng l 30. Xc nh hm cung mi. Tnh sn lng vgi c cn bng trong th trng ny.c/ Nu chnh ph n nh mc gi sn Pr = 350 th lng d tha l bao nhiu.trong trng hp chnh ph mua ht lng d tha: xc nh doanh thu ca nh sxtrc v sau khi chnh ph p dng gi sn, xc nh chnh ph phi chi ra chochnh sch ny

a/ Khi can bang thi Qs=Qd => 3280-8P=282+2P => P=300 =>Q=880Ed=Qd'*P/Q=-8*300/880=-2.73Es=Qs'*P/Q=2*300/880=0.75b/Ban co the noi ro hon cau nay uoc ko? chinh phu anh thue vao tung san pham hayanh thue tong cong la 30?c/ Neu chinh phu at gia san P=350 thi Qs=982 va Qd=480 => luong du thua la DT=502Truoc khi at gia san thi doanh thu cua nha SX la: TR1=P*Q=264000Sau khi at gia san :TR2=350*982=343700Chinh Phu phai chi ra mot khoan T=(982-480)*350=175700

Xt th trng c quyn hon ton. h s cu: P = 1240-2Q. hm tng chi ph cadoanh nghip: TC = 3Q2 + 240Q + 35000a/ Xc nh hm s: TFC, TVC, AFC, AVC, ATC, MC ca doanh nghip.b/ Xc nh sn lng v gi ti a ha li nhun? tnh li nhun ca doanhnghip?c/ Tnh h s lerner v cho bit quyn lc c quyn ca doanh nghip cao haythp?d/ Nu th trng cnh tranh hon ho th gi bn v sn lng bao nhiu?e/ Nu chnh ph nh gi trn Pc = 980 th doanh nghip s sx bao nhiu? lngthiu ht l bao nhiu

a/ Ta c khi Q=0 Th FC=TC => FC=35000


6/23

=> AFC=FC/Q=35000/QVC=TC-FC=3Q^2+340Q=> AVC=VC/Q=3Q+340=>ATC=TC/Q=3Q+340+35000/QMC=VC'=6Q+340

b/ Ta c TR=P*Q=1240Q-2Q^2=> MR=TR'=1240-4Q ti a ha li nhun MC=MR 1240-4Q=6Q+340 =>Q=90=>P=1060 =>LN=TR-TC=14500c/ H s Lener : L=(P-MC)/P=(1060-880)/1060=0.17=> Quyn lc c quyn ca doanh nghip thpd/ Nu th trng l cnh tranh hon ho th MR=P=> ti a ha li nhun MC=P 1240-2Q=6Q+340 =>Q=112.5 =>P=1015e/ Nu Chnh Ph t gi trn P=980 th XN s SX lng sn phm Q=107 trong khilng cu l Q=130 => lng thiu ht =23

Hm cung v hm cu ca loi bnh AFC trn th trng nm 2007 nh sauhm cung : Qs = 12P - 15hm cu : Qd = -8P + 45(Q : ngn hp, P : ngn ng / hp)a/ Gi v sn lng cn bnng trn trng ca bnh AFC nm 2007 l bao nhiu ?b/ Do nhu loi bnh mi xut hin trn th trng, cu v bnh AFC nam 2008gim 10%. hy tnh tc ng ca vic gim cu ny i vi gi v sn lng bnhAFC u nam 2008 ?c/ Tnh co gin ca cung v cu bnh AFC theo gi ti im cn bng nm 2007v 2008 ?

a/ Th trng cn bng Qs=Qd => 12P -15= - 8P + 45 => P = 3 => Q = 21b/Do c tc ng nn lng cu gim 10% =>Qd* = 90%Qd = -7.2P + 40.5=>Khi th trng cn bng th gi v lng sn phm u nm 2008 : Qd* = Qs =>-7.2P + 40.5 = 12P -15=> P = 2.9 => Q = 19.7c/ Nm 2007Ti im cn bng: Ed = Qd'*P/Q = - 8*3/21 = -1.143Es = Qs' * P/Q = 12*3/21 = 1.174Nm 2008Ti im cn bng: Ed = (Qd*)' *P/Q = -7.2*2.9/19.7 = -1.06Es = Qs'*P/Q = 12*2.9/19.7 = 1.766

Hm cung v cu th trng ca sn phm X c cho nh sauQd = -2P + 100Qs = 2P - 20(P: ngn ng/ sn phm, Q : ngn sn phm)a/ Xc nh gi v sn lng cn bng trn th trng. Tnh thng d tiu dng,thng d sn xut v tng thng d x hib/ Nu chnh ph nh gi trn cho sn phm X l 25. Hy tnh lng thiu ht


7/23

c/ Nu chnh ph nh gi cho sn phm X l 35. tnh lng d thad/ Nu chnh ph nh thu 5 ngn ng / sp. hy tnh gi v sn lng cn bngtrn th trng, khon thu trn mi sn phm m ngi tiu dng v ngi snxut phi chu, khon thu m nh nc thu c

a/ Khi th trng t cn bng Qs=Qd => -2P+100=2P-20 =>P=30 =>Q=40P=-Qd/2+50P=Qs/2+10Thng d tiu dng: CS=1/2*(50-30)*40=400Thng d sn xut: PS=1/2*(30-10)P40=400=> Tng thng d x hi: =PS+CS=800(My ci ny v hnh th tnh ton s d dng hn )b/ Nu chnh ph t gi trn l 25 th lc lng cu v lng cung ca th trng l:Qd=50,Qs=30=> Lng thiu ht l TH=50-30=20c/ Nu chnh ph t gi sn l 35 th:

Qs=30,Qd=50=> Lng d tha: DT=50-30=20Mt hng sn xut c hm cu l:Q=130-10Pa) Khi gi bn P=9 th doanh thu l bao nhiu?Tnh co gin ca cu theo gi timc gi ny v cho nhn xt.b) Hng ang bn vi gi P=8,5 hng quyt nh gim gi tng doanh thu.quytnh ny ca hng ng hay sai?V sao?c) Nu cho hm cung Qs=80, hy tnh gi v lng cn bng?Tnh co gin cacu theo gi ti mc gi cn bng v cho nhn xt.

a) Ta c: P=9 thay vo pt ng cu ta c: Q=130-10x9=40.Ta li c TR=PxQ= 9x40= 360Vy khi gi bn l P=9 th doanh thu l TR= 360.Ta c: Q= 130-10P => (Q)`= -10 co gin ca ng cu = (Q)`x P\Q= -10x9\40= -2,25Vy khi gi thay i 1% th lng cu thay i 2,25%b) Khi gi l P= 8,5 th lc lng cu s l Q=130-10x8,5=45Lc doanh thu s l TR= 8,5x45=382,5Vy khi hng quyt nh gim gi th doanh thu t c ln hn. Quyt nh ca hng lng.c) Ti v tr cn bng ta c: Qd=Qs 130-10P=8010P=50P =5=>Pe=5.Qe=Qs=80.Vy mc gi cn bng l P=5, mc sn lng cn bng l Q=80 co gin ca dong cu= -10x5/80= -0,625.Vy khi gi thay i 1% th lng s thay i 0,625%


8/23

Mt ngi tiu dng c thu nhp l I -1,5triu/thng mau hai hng ha X v Y.Gi ca hng ha X l 15,000ng/kg v hng ha Y l 5000 ng/kg Hm tng lich c hco bi TU = 2XYA. Xc nh kt hp tiu dng ti u? Li nhun ha ti a thu c bao nhiu.?B. Nu thu nhp tng ln gp i th kt hp tiu dng ti u mi l bao nhiu?

C. Nu thu nhp ca ng tiu dng vn l 1,5 triu/thng nhng gi ca hng ha Xgim cn 10,000ng/kg, Xc nh kt hp tiu dng ti u mi.

a/Ta c: MUx=2Y, MUy=2X=> kt hp tiu dng ti u th X,Y phi tha mn h phng trnh:15000X+5000Y=1500000MUx/MUy=Px/Py=>X=50,Y=150 =>li nhun ti a thu c l: TU=2*50*150=15000b/ Nu thu nhp tng ln gp i m gi cc hng ha khng thay i th kt hp tiudng ti u l : Xo=2X=100 , Yo=2Y=300 (ta cng c th dng cch gii nh cu a gii phn ny)

c/Nu gia hng ha X gin cn 10000 th kt hp ti u th X*,Y* phi tha mn hsau10000X*+5000Y*=1500000MUx/MUy=Px/Py=> X*=75,Y*=150

mt hng c quyn c ng cu Q=120-P tng chi ph ngn hn TC=2Q(lpphng)-6Q(bnh)-31Q+120a, vit phng trnh biu din cc chi ph ngn hnhng s sn xut ban nhiu sn phm ti a ha li nhun.khi gia bn,tngdoanh thu,tng chi ph v li nhun ca hng l bao nhiu?xc dnh mc sn lng hng ti a ha doanh thu.khi gi bn, tng doanh thu,tng chi ph v linhun ca hng l bao nhiu?d,gi s chnh ph dnh thu l 30 ng/1 n v sn phm .khi gi bn, doanhthu,li nhun s thay i nh th no?

a/ Ta c:khi Q= 0 th FC=TC =>FC=120 =>VC = 2Q^3 - 6Q^2 - 31QMC= TC'=6Q^2 - 12Q - 31TR=P*Q=Q*(120 -Q)=120Q -Q^2=> MR=TR'=120 - 2Q ti a ha li nhun th MC=MR=> 6Q^2 -12Q -31=120 -2Q => Q=5.9 =>P= 114.1=> TR=673.2, TC= 139, LN=534.2 ti a ha doanh thu th MR=0=> 120 -2Q=0 =>Q=60 =>P=60, TR=3600, TC=214260 ,LN= -210660 (l)b/ nu chnh ph nh thu 30/sp th chi ph cn bin s thay iMCo=120 -2Q +30=150-2Q ti a ha doanh thu th MR=MCo=> 6Q^2 - 12Q - 31=150 - 2Q => Q=4.7 ,P=115.3 ,TR=541.9 ,TC= 190.4 (lc ny hm


9/23

tng chi ph l : TC= 2Q^3 - 6Q^2 -31Q +120 + 30Q)=> LN=351.5cu v sn phm X l P=90-Q.th trng ny do 1 hng c quyn khng ch.chi phca hng c quyn C=480+q^2+4qa, hy xc nh gi v sn lng cn bng cho hng c quyn ny

b, hng tao ra bao nhiu li nhun v thng d tiu dng?nu hng mun ti a hadoanh thu th phi chn mc gi v sn lng l bao nhiu?khi li nhun thuc l bao nhiu?c, gi s chnh ph t gi trn l 60 th hng sn xut bao nhiu t c linhun ln nht?luc thng d tiu dng l nh th no?

a/ Gi v sn lng cn bng khi v ch khi Ed = Qp'*P/Q = - 1=> -1*(90 -Q)/Q =-1 => Q=45, P=45b/ Ti im cn bng : TC= 2685, TR= P*Q= 2025 => LN= -660 (l)Thng d tiu dng: CS= 1/2*(90-45)*45 = 1012.5(ci ny bn v hnh th tnh ton s d dng hn)

TR= P*Q =90Q - Q^2 => MR= 90 - 2Q ti a ha doanh thu th MR=0 => P= Q = 45=> LN= -660 (nh trn)Bn cng c th ni lun rng khi gi v sn lng cn bng thi doanh thu t ti ac/ Nu chnh ph t gi trn l 60 th luc TR =60* Q, TC= 480 + Q^2 + 4Q => LN= TR - TC = 56Q - Q^2 - 480 li nhun t ti a Q= 28 => LN = 304Lc CS= 420 (ci ny bn phi v hnh thi)

mt hng c quyn c ng cu Q=50-P; AVC=Q-6; FC=40a, gi v sn lng ti a ha li nhun ca hng l bao nhiu?tnh li nhun ti a ?b, xc nh h s co dn ca cu ti im ti a ha li nhunc, nu chnh ph t gi trn l 25/1 on v sn phm th nh c quyn s sn xutbao nhiu?li nhun ca n s l bao nhiu?d, gi s chnh ph tr cp 6 ng/1 n v sn phm v t mc gi sao cho nhc quyn sn xut mc sn lng cao nht th chnh ph phi chn mc gi no?

a/ Ta c:TR=Q*P=50Q-Q^2 => MR=50-2QVC= AVC*Q=Q^2 - 6Q => MC= 2Q - 6 ti a ha li nhun th MC=MR => 4Q= 56 =>Q=14, P=36=> LN= TR - TC =TR - VC -FC = 352b/Ti im ti a ha li nhun th: Ed= Qp'*P/Q = -2.57c/Nu chnh ph t gi trn l 25/1vsp thP= 50 -Q = 25, TR= 625, TC= VC + FC = 515 => LN = 110

th trng sn phm A coi l canh tranh hm cu v hm cung c cho bi sauy:Pd=100-Q


10/23

Ps=10+Qa, xc nh mc gi v sn lng cn bng ?b,tnh thng d tiu dng v thng d sn xutc, nu chnh ph n nh mc gi P=50 th iu g s xy ra?d, nu chnh ph nh thu 10 /1 sn phm bn ra th im cn bng ca th

trng s thay i nh th no?a/ Ti im cn bng th:Ps=Pd => 100-Q=10+Q =>Q=45 ,P=55b/ Thng d tiu dng; CS=1/2*45*(100-55)=1012.5Thng d sn xut: PS=1/2*45*(55-10)=1012.5c/ Nu chnh ph n nh mc gi l P=50 th lng cu l Qd=60 trong khi lngcung l Qs=40 => thiu htd/ Nu chnh ph nh thu 10$/1sp th nh sn xut s ng bn sn phm vi mc giPs'= 20+Qs=> im cn bng mi Pd=Ps' =>20+Q=100-Q

=> Q=40,P=60mt hng canh tranh hon ho c AVC=3Q+4a, xc inh cung sn phm ca hngb,nu gi bn l 55 th hng l l 120 hy xc inh gi v sn lng ha vn cahng khi chi ph c nh ca hng l bao nhiu?c, nu gi bn ca th trng l 60 hy xc inh mc sn lng ti a ha li nhunca hng.khi doanh thu v li nhun ca hng l bao nhiu?d, hy xc nh thng d sn xut ti im ti a ha li nhun?

a/ Ta c: VC=AVC*Q=3Q^2+4Q => MC=VC'=6Q+4Do y l th trng cnh tranh hon ho nn ng cung ngn hn ca hng chnh lng chi ph cn bin nm pha trn AVC minhay P= 6Qs +4 (vi Q>=0)b/ TC=VC+FC=3Q^2 +4Q +FCKhi P=55 =MR (Do cnh tranh hon ho)=> Q=8.5=> TR=P*Q=55Q,TC=250.75+FCTa li c TR-TC=-120 => 467.5-250.75-FC=-120 => FC=336.75=> TC=3Q^2+4Q+336.75 => ATC=3Q+4+336.75/Q >= 67.5Ti im ha vn P=ATCmin=67.5c/ Nu P=60 =>MR=60 ti a ha li nhun th MC=MR =>Q=28/3=9.3=>TR=560,LN=-75.4d/ Ti a ha li nhun trong cu ny ng vi P=? vy hay l dng P cu trn

1 doanh nghip c quyn mua vi biu cu:P 50 40 30 20 10Q 5 10 15 20 25T cho s liu hp l hm AE?Xc nh sn lng doanh nghip ti a ha li nhun?


11/23

Xc nh Ps (thng d sn xut) m ngi bn b mt?Chnh ph nn quy nh gi no ti a ha tng thng d?

1.hm AE chnh l hm cung ca doanh nghip c quyn mua .bn ch cn cho hm h s gc dng l c.

hm cu ca doanh nghip c quyn mua tnh c l P=60-2Q.m hm cu ca doanhnghip trng vi hm MV=>MV=60-2Q.ta cho hm AE=Q+20=>S=Q+20 vME=2Q+20. ti a ha li nhun th MV=ME 60-2Q=2Q+20 Q=10 =>P=302.V hnh ta thy MV=Ps=>Q*=40/3=>P*=100/3PS*=1/2(100/3-20).40/3=800/9PS=1/2(30-20).10=50=>PS-PS*=350/93.Chnh ph s quy nh gi ti P* khong b mt khng hay tng thng d l ti a

Mt doanh nghip sn xut vi AC=300 + 96500/Q v ng cu P=1000-Q

a, quyt nh ca doanh nghip ti a ha li nhun l bao nhiu?tnh li nhun lnnhy ?b, doanh nghip s t gi no ti a ha doanh thuc, xc nh mc gi v sn lng doanh nghip bn c nhiu sn phm nhtm khng b l?d, mc sn lng ti u cho xa hi l bao nhiu? v li nhun ca doanh nghip lbao nhiu?

y l doanh nghip c quyn t nhin do AC=300+96500/Q=>TC=300Q+96500=>MC=300.M MR=1000-2Q ti a ha li nhun th:MR=MC1000-2Q*=300=>Q*=350,P*=650,TR=227500,TPmax=26000b>ti a ha doanh thu:MR=0Q=500,P=500,TRmax=250000,TP=3500c> la chn sn lng ln nht m ko b l th TR=TC(1000-Q).Q=300Q+96500Q=511,26 V Q=188,75(Loi)=>P=488,74d>do l doanh nghip c quyn t nhin nn sn lng ti u ca x hi chnh lQ=511,26 v hnh ta thy ngay.TP=0.Do gi v sn lng lm trn nhiu qu nn tnh kora TP=0.Bn ly s c th nha

biu sau y vi ng cu ca sn phm Y.vi chi ph binh qun khng i l14USDGI(ng/sp) 24 21 18 15 12 9LNG(1000d/sp) 0 700 1400 2100 2800 3500a, hy xc nh gi v sn lng ti a ha li nhun cho nh c quyn ?khi doanh thu v li nhun l bao nhiu?b, hy xc nh h s co dn ca cu v tnh thng d tiu dng ti mc gi ti aha li nhunc, hy xc nh h s sc mnh c quyn v phn mt khng?d, gi s chnh ph nh thu c nh T=1000 vo nh c quyn khi gi v snlng thay i nh th no?


12/23

e, gi s chnh phr nh thu l 2USD/1sp bn ra khi gi,sn lng,doanh thu vli nhun thay i nh th no?f, x hi c li g nu nh c quyn sn xut im cn bng cnh tranh ?aic li v ai b thit?

gii h pt ta c:P=24-3/700.Q.MC=AC=14,MR=24-3/350QMR=MCQ*=3500/3,P*=19,TR=66500/3,TP=17500/3b>E=-700/3.19.3/3500=-19/5CS=1/2.(24-19).3500/3=17500/6c>L=-1/E=5/19,PS=(19-14).3500/3=17500/3d>nh thu c nh th ko nh hng n mc sn lng v gi nhng TPm=TP-1000e>MCt=MC+2=16.MR=MC24-3/350Q=16=>Qt=2800/3,Pt=20,TRt=56000/3,TPt=11200/3f>lc ny x hi ko c mt ko v ngi c li l tiu dng do CS Tng v ko c li ldoanh nghip v PS gim?

Mt hng c quyn c ng cu v sn phm l P= 30-0.5Q , hm tng chi phca nh c quyn nu l TC= 14Q1, Tnh gi v sn lng ti a ha li nhun . Tnh gi tr thng d tiu dng vthng d sn xut ti mc gi v sn lng ti u ny .2, Tnh ch s o lng sc mnh ca nh c quyn v phn mt khng do nh dcquyn gy ra .3, Khi chnh ph thu thu l 1/ n v sn phm th gi v sn lng ti u cngnh li nhun ca nh c quyn thay i nh th no ?4 , V th minh ha

1.TR=P*Q=30Q-0.5Q^2=>MR=30-QMC=TC'=14Ti a ha li nhun MR=MC => Q=16=> P=22Thng d tiu dng: CS=1/2*(30-22)*16=64Thng d sn xut: PS=TR-VC=1282. Ch s sc mnh : L=(P-MC)/P=0.27Nu l th trng hon ho th:Tng ch li x hi = PS*+CS*= 240=> Phn mt khng do th trng c quyn gy ra:DL=PS*+CS*-PS-CS=483. Khi chnh ph nh thu 1/1sp th hm chi ph cn bin lc ny l:MC*=15 ti a ha li nhun th: MR=MC* => Q=15,P=15LN= TR-TC=0

Gi nh hm s cung v hm s cu th trng go ca Vit Nam l:Qs=20P-100 v Qd=80-10Pa) Hy xc nh gi c cn bng,s lng cn bng v m t bng th?


13/23

b) h tr cho ngi tiu dng,nh nc n nh gi ti a P=5.5 ,hi lngthiu ht trn th trng l bao nhiu?c) gii quyt lng thiu ht ,nh nc nhp khu go vi gi quy i l 6.5,trng hp ny ngn sch nh nc phi b l s tin l bao nhiu ?L ngi tiudng bn c li g khi nh nc thc hin nhp khu thay v phn phi theo nh

lng /?a) cn bng th trng Qs= Qd20P-100=80-10P P*=6 => Q*=20(bn v ng cung ng cu ln th th im m 2 ng y ct nhau chnh l imcn bng, gi cn bng =6 v lng cn bng = 20)b) khi chnh ph p t gi P=5,5$ < P*khi Qs=20*5,5-100=10 v Qd=80-10*5,5=25=> Qd>Qs=> thiu ht th trng = Qd-Qs= 25-10=15c) gii quyt lng thiu ht, nh nc phi nhp khu vi gi 6,5$ =>vi lng thiuht l 15( n v g ) th s ngn sch nh nc phi chi = 15*6,5=97,5($)* l ngi tiu dng,khi chnh ph phi nhp go b phn thiu ht do chnh ph p

t gi trn < gi cn bng, th chng ta- nhng ngi tiu dng s mua c sn phmvi gi r hn, nn s mua nhiu hn;)

Th trng sn phm X c hm cung v cu c dng=60-1/3Qd ,p=1/2Qs-15a)Gi s chnh ph nh thu l gim sn lng cn bng xung v bng 84.Xcnh mc thu chnh ph nh vo mi sn phm la bao nhiu?b) tin thuu m ngi tiu dng phi chu trn mi sn phm?c)S thay i trong thng d tiu dng v thng d sn xut khi chnh ph nhthu?d) tn tht v ch xy ra khi chnh ph nh thu

a)* Cn bng cung cu khi chnh ph cha nh thu 60-(1/3)*Q=(1/2)*Q-15Q*=90=>P*=30v khi c thu, sn lng cn bng gim=> thu nh vo cu( gia tng=> cu gim)* Gi s chnh ph nh thu mi sn phm l t($)khi hm cumi l Pd'= Ps+t=(1/2)*Q-15+t=>cn bng cung cu mi l 60-(1/3)*Q=(1/2)*Q-15+tm lng cn bng mi l 84, thay vo phng trnh cn bng cung cu mi => t=......vy chnh ph nh vo mi sn phm l......$B)Gi cn bng sau khi c thu l P=......=> so vi gi cn bng lc u th ngi tiudng s c mua dt hn... /1 sn phm=> ngi tiu dng phi chu...../1 sn phmc)cu c v d, bn ch cn v hnh ra l s thykhi cha c thu, thng d sn xut l phn din tch nm di ng gi cn bng,trnng cung,thng d tiu dng l phn din tch nm trn ng gi cn bng, ding cu**** Khi c thu, th thng d sn xut l phn din tch nm trn dng cung, ding gi cn bng mi, v c ging ln t lng cu Q=84 na( b chn y), thngd tiu dng l phn din tch di ng cu, trn ng gi cn bng mi, v cng bchn bi ng thng ging t 84 thng ng ln


14/23

Cho hm s cung v cu ca sn phn X c dng P= Q+ 20 v P= -2Q+ 140. Nuchnh ph nh thu mi Click herel 9vt, th gi cn bng mi l bao nhiu?

nu ko i th th ny nh:

Nu chnh ph nh thu mi sn phm l 9dvt ==> Hm cung mi nh :P=Q + 20 + 9 = Q + 29 (1)Hm cu gi nguyn : P= -2Q + 140 (2)Gi bn gii h 2 ptrinh (1) v (2) l c gi v lng cn bng mi. ( P*, Q*)

Cho cc thng tin sau v th trng sn phm A: Ga th trng t do ca sn phml 10 nghn ng/n v, sn lng trao i l 20 nghn n v. Co gin ca cu theogi hin hnh l -1, co gin cung mc gi l 1.a. Hy vit ptrnh ng cng v ng cu ca th trng v sn phm ny, bitrng chng l ng thng.b. V th ng cung v ng cu va tnh c

c. Tnh thng d tiu dng, thng d sn xut v li ch rng x hi mc gi cnbng th trng.d. mc gi v sn lng ny tng doanh thu bng bao nhiu v t ti acha?

a)Gi s phng trnh ng cu l Q=aP+b (a


15/23

Mt hng cnh tranh hon ho in hnh c tng chi ph ngn hn: TC= 100+ 7Q +Q.Q v TC= 4Q + Q.Qa) Tm sn lng ti u ca hng gi 35$/ v? Li nhun ti a thu c?b) Mc gi cn bng ca th trng di hn? Khi gi th trng gim xun 25$/ v

th hng nn ng ca sn xut khng? ti sao/c) Xc nh ng cung ngn hn, di hn ci hng?

Mc gi cn bng di hn xc nh bi im y ca ng LACta c P=LAC min=4c- Gi ha vn P=27$ bng cch gii pt MC=ACGi ng ca Po=7$ bng cch gii pt MC=AVC mc gi Po=7$


16/23

1). Mt hng CTHH c hm chi ph bin i bnh qun nh sau: AVC = 2Q+4 ($)1.Khi gi bn cu sn phm l 24$ th hng b thua l l 150$.Tm mc gi v snlng ha vn ca hng?2. Hy xc nh ng cung ca hng v thng d sn xut ti mc gi 84$?

2 ) K hiu ca mn hc ny tht nhiu, v hay nhm na khng bit anh c cchno phn bit chng v d nh khng a?nhiu cng thc na ch?V dSAC,ATC,AVC,SMC,LAC....hu.

1) AVC = VC/Q=> VC= AVCxQ= 2Q^2+4QMC= VC'= 4Q+4Doanh nghip ha vn => P=MC; P= AC (1)Ta c li nhun pi = TR - TC= Q(P-AC) khi p= 24$ th hng b thua l 150$ Q(24-AC)= -150 (2)Kt hp 1 v 2 gii c P= AC= 40,4 ;Q= 9,12) ng cung S=MC

3) bn ch cn phn bit A: bnh qun, M: cn bin ; S: ngn hn; L: di hn; C: chi ph;T: tngvd: SAC l chi ph bnh qun ngn hn

mt hng c hm sx l Q=5KL hng s dng 2 u vo l vn K v lao ng L. gica u vo tng ng l 2$/1 v vn; w=4$/1 v lao ng1. gi s hng c mc chi ph l TC =$50000, khi hng s la chn mc u voti u no ti a ha sn lng?2. gi s gi ca vn tng ln 2 ln gi lao ng khng thay i hy tnh li cu 1?

Q=5KL =>MUk= Q'k=5L ; MUl=Q'l= 5Kr=2; w=4; TC=50 000 => 2K + 4L=50000(1)iu kin ti a ha sn lng: MUk/r =MUl/w=> L/2=K/4 hay L=2KTh vo (1): 10K=50 000 => K=5000 =>L= 10000cu 2 lm tng t vi r=4 nh!

Mt DN c quyn c chi ph cn bin ko i l 300$. Doanh thu bin = 1000 - 2Q.Khi DN sn xut ra 500 sp th chi ph cho mi n v sp l 365$. Yu cu:

1, Nu c ton quyn hnh ng th DN s sn xut mc gi v sn lng no ti a ha li nhun v ti a ha doanh thu.

2, DN nn t gi bao nhiu bn c nhiu sp nht m ko b thua l khi mi bcvo th trng.

3, Gi s chnh ph quy nh mc thu t/v sp bn ra khi gi bn sn lng vli nhun ca DN theo ui s thay i ntn? Xc nh t chnh ph thu c tin caonht.


17/23

1)ti a ha li nhun TP: cho MR=MC (MR l doanh thu bin nh.MC l chi ph cnbin nh)=>Q*=350.by gi ta tnh TP max.trc tin tm pt g cu D of dn.TR (doanh thu) l ng hm of MR=>MR=1000Q-Q'2'=>pt g cu D l P=TR/Q=1000-Q

Q*=350 th P*=650.tm TC nhe(TC l tng chi ph ca dn).(TC)'=(FC+VC)'=(VC)'=MC.=>VC l ng hm of MC=>VC=300*Q.(FC l chi ph cdnh nh,VC l chi ph bin i)

chi ph cho xs 500sp l 500*365=>500*365=VC+FC=300*500+FC=>FC=32500.t =>TC=300Q+32500=137500TR=P*Q=227500=>TP=90000

ti a ha doanh thu TR: th cho MR=0=>P,Q nh.

2)hng t gi P=ATC(ATC l tng chi ph bing qun)m P=TR/QATC=TC/Q=>TR=TC hay 1000Q-Q'2=300Q+32500.gii ra nha.

3)c thu th MCt=MC+t=300+tcho MR=MCt rt ra c Q=350-t/2ttongr s thu cphu thu c l T=t*Q =>T=350t-t'2/2Tmax khi T'=0 suy ra t=350 nha.t tnh c Q,P,TP khi c thu nha.vy Q gim,P tng,li nhun b mcn tng hay gim c th bao nhiu th bn t lam php tr nh

C hm cung v cu nh sau:Qs = 12 + 2PQd = 40 - 5Pa) Tnh sn lng v gi cn bng.b) Tnh co gin ca cu v cung theo mc gi cn bngc) tng tng doanh thu cng ty nn tng hay gim gi nu hin ti cng ty angbn mc gi P = 6?d) Tng doanh thu ca cng ty ln nht mc gi no?

a,ta c im cn bng Qs=Qd vy P=4; Q=20b, co gin ca cung l Esp=2.4/20=0,4


18/23

co gin cua cu l:Edp=5.4/20=1c, tng doanh thu th cog ty phi gim gi bn v hin ti cg tty ang bn vi ga caohn v tr cn bng do lm lng ngi mua t id, doanh nghip t tng doanh thu ln nhtta co tng doangh thju nh sau:TR=P.Q=P(40-5P)

ta thy rng TR l hm bc hai vy TRmax khi o hm TRmin hay ni cch khc l hmbc hai c b lm quay ln pha trn40-10P=0 vy P=4vy P=4 th tng doanh thu ln nht

Mt ngi tiu dng c thu nhp l I = 1.5triu ng/thng mua hai hng ha Xv Y.Gi ca hng ha X l 15.000 ng/kg v hng ha Y l 5000 ng/kg.Hmtng li ch c cho bi TU=2XY.a.Xc nh kt hp tiu dung ti u?Li ch ti a thu c l bao nhiu?b.nu thu nhp tng ln gp i th kt hp tiu dng ti u mi l bao nhiu?c.Nu thu nhp ca ngi tiu dng vn l 1.5 triu ng/thng nhng gi ca hng

ha X gim xung cn 10.000 ng/kg.Xc nh kt hp tieu dng ti u mi.Ta c Mux/Px= 2y/15000, Muy/py=2x/5000 v X.Px + Y.Py = I 15000X + 5000Y= 1.5trkt hp 2 phng trnh Mux/Px = Muy/py v X.Px + Y.Py = Igii pt ra tm X, Y l xc nh c cch kt hp tiu dng ti uC X, Y thay z TU = 2XY l tm c li ch ti aMy cu di tng t thi;)

Cho biu thc xc nh sn phm bin ca lao ng l (14 - 0,08L) vi L s lnglao ng .

a.Hy tm biu thc m t cu v lao ng vi tin cng danh ngha W v mc gi P.b.Xc nh cu v lao ng khi tin cng danh ngha bng 4 nghn , 3 nghn , 1nghn ng vi mc gi bng 1 .c.V th ng cu lao ng .

Gi s l tin lng tt c cc cng nhn l nh nhau W.Khi DN thu thm 1 cng nhn th h phi b ra W tinH thu v (14-0,08L) sn phm v bn vi gi PNh vy h thu v t 1 cng nhn l (14-0,08L)PTin lng W l khng i, P khng i , m (14-0,08) gim dn. Do cng thu nhiuth li nhun bin cng gim dn. DN s ti a ha li nhun khi ln nhun tng thmbin = tin lng tr cho cng nhn thu thm. Theo :W=(14-0,08L)PChuyn v tnh ton ta s c L= 175 - 12.5w/p (ging ch duyhien)Nh vy l c biu thc v cu lao ng ri .


19/23

b/ Ch cn thay s tnh ton .P=1000, W=4000, L=125P=1000,W=3000, L=137.5Cc Bn t tnh tip nha;)V th, v ng thng L = 175 -12.5w/p : trc honh l w/p, trc tung l L, ng

thng i xung1. ng thc no di y ch ra s ti a ha li ch i vi hai hng ha X1 vX2:a. MUx1 = MUx2 b. MUx1/MUx2 = Px1/Px2 c. MUx1/Px1 = MUx2/Px2 d. C b v c2. Th trng cho hm cung cu sau Q = P-6 v Q= 22-P. Thng d tiu dng vthng d sn xut ti im cn bng l:a. CS =32:PS=23 b. CS=23;PS=23c. CS=32 ; PS=32 d. Khng kt qu no ng.3. Mt doanh nghip c TR = 1000Q - 10Q v VC=100Q+5Qa. X nh Gi v sn lng khi doanh nghip theo ui mc tiu ti a ha li

nhun.?b. Xc nh gi v sn lng khi doanh nghip theo ui mc tiu ti ha doanhthu.c. Nu nh thu t=10/sp xc nh gi v sn lng ti a ha li nhun sau thu?d. V th minh ha cc kt qu.

1. ng thc no di y ch ra s ti a ha li ch i vi hai hng ha X1 v X2:a. MUx1 = MUx2 b. MUx1/MUx2 = Px1/Px2 c. MUx1/Px1 = MUx2/Px2 d. C b v c2. Th trng cho hm cung cu sau Q = P-6 v Q= 22-P. Thng d tiu dng v thng dsn xut ti im cn bng l:a. CS =32:PS=23 b. CS=23;PS=23c. CS=32 ; PS=32 d. Khng kt qu no ng.3. Mt doanh nghip c TR = 1000Q - 10Q v VC=100Q+5Qa. X nh Gi v sn lng khi doanh nghip theo ui mc tiu ti a ha li nhun.? ti a ha li nhun th MR=MC =>> P=700,Q=30b. Xc nh gi v sn lng khi doanh nghip theo ui mc tiu ti ha doanh thu.TI A HA DOANH THU TH MC=0 =>>P=500, Q = 50c. Nu nh thu t=10/sp xc nh gi v sn lng ti a ha li nhun sau thu?NU NH THU TH MCt= MC+10 =>> MCt=MRd. V th minh ha cc kt qu.Bi 1:Mt nn kinh t ng c thu ph thuc vo thu nhp. T=tY, chi tiu h gia nhC=100+0.8Yd u t d kin I =225, chi tiu chnh ph G=325

a. xc nh thu sut m bo ngn sch cn bng tai mc sn lng cn bngb. Nu thu sut t= 0.4 hy xc nh mc sn lng cn bng v cn cn ngn schti mc sn lng .c. Nu chi tiu chnh ph gim xung 1 lng l 52 v thu sut l 0.4 th sn lngcn bng mi thay i ntn?


20/23

Bi 2Mt nn kinh t c cc thng s sau : C=100+0.8 Yd, I=40+0.16Y,T=50+0.2Y,G=200,X=100,IM=25+0.05Ya. Xc nh mc sn lng cn bng c nhn xt g v tnh trng ngn sch v cncn thng mai.

b. Nu xut khu tng thm l 17.5 tnh mc sn lng cn bng mi. Cn cnthng mi thay i theo chiu hng no?

V nguyn tc ta c cng thc tng qut sau :Y = C + I + G + NX (net export)

trong :- NX (xut khu rng) = xut khu - nhp khu = X- Im- C thng l mt hm tuyn tnh ca Yd; Yd (Y kh dng ) = thu nhp - thu = Y- T- Cch tnh T nh th no, u bi s cho, thng thng T t l vi Y : T= tY

T cng thc trn ngi ta cho nhiu d liu phc tp, v d nh bi 2 , cng ch lmri mt mnh m thi.

Bi 1:cu a: chu !Cha gp cu ny bao gi.cu b: phng trnh trn trong bi ny s l :

Y = 100 + Yd + 225 + 325 (do kinh t ng nn k c NX)= 100 + (1-t)Y + 225 + 325vi t= 0.4 th Y = 1625

ngn sch thu vo 1625*0.4 =650. Trong khi chi tiu chnh ph ch c 325, vy thngd 650-325 =325 (ci ny ch c trong l thuyt thi, he he)

c, chi tiu chnh ph gim 52 th G=325-52= 273.Tnh tng t phn a, ta c Y=1495.Hoc n gin hn l ly 1625 ban u tr i 52/0.4

Bi 2 : phng trnh trn tr thnh :Y= C + I+ G + NXY= C + I+ G + X - ImY= 100+0.8 Yd + 40+0.16Y + 200 +100 - 25-0.05Y

C Yd = Y-T => Y = 100 + 0.8 (Y- 50-0.2Y) + 40 +0.16Y + 200 + 100 - 25 - 0.05YY = 375 +0.75Y= > Y = 1500

Ngn sch thu bng thu l 350, chi tiu chnh ph l 200, vy ngn sch thng d 150Nhp khu t 100, vy thng mi cn bng.


21/23

b, khi X= 117.5 => Y = 1570Im=103.5 => thng d thng mi 14

Mt hng bit c hm cu v sn phamcuar mnh l: P=100-0.01Qd; trong Ql sn lng tnh bng n v. Hm tng chi ph c hng l:TC=50Q+30000

1.Vit phng trnh biu din tng doanh thu, doanh thu bin, chi ph bin2.Xc nh sn lng ti u hng c th ti a ha li nhun.3.Nu hng phi chu thu t=10vtt/n v sn phm th sn lng, gi c l baonhiu hng ny c th ti a ha li nhun?

P=100-0.01Qd, TC= 50Q+300001. TR= P*Q= 100Q- 0.01Q2MR= TR'=100- 0.02Q , MC= TC'= 502. ti da ha li nhun: pi max MR=MC100-0.02Q= 50=> Q= 25003. TC= 50Q+30000+10Q=60Q+30000Pi max MR=MC60 = 100-0.02QQ=2000=> P= 80

01doanh nghip c hm s cu :P= 16-Q+24/Q ;v TC = 43+4Qa. hy vit hm s chi ph bin, doanh thu, chi ph bin, chi ph bin i, li nhunb. Hy xc nh sn lng, tng doanh thu, tng li nhun, gi th trng trong cctrng hp :+ Khi DN theo ui mc tiu ti a ha li nhun+Khi DN theo ui mc tiu ti a ha s lng bn vi iu kin khng l+ Khi DN theo ui mc tiu ti a ha doanh thu khng km theo iu kin rngbuc+ Khi DN theo ui mc tiu tng li nhun =16+ Khi DN theo ui mc tiu t li nhun nh mc trn chi ph bnh qun 20%

a. chi ph bin : MC = TC'=4doanh thu TR= P*Q=16Q- Q2+24chi ph bin i VC= 4Qli nhun pi = TR-TC=12Q-Q2-19B. khi DN theo ui mc tiu ti ha li nhun : pi max khi MR=MCMR = TR'= 16- 2Q=>16-2Q=4=>Q=6, P= 14, TR= 84, TC= 67, pi = 84 -67 = 17khi DN theo ui mc tiu ti a ha doanh thu : TR m khi MR = 0=>16-2Q = 0=>Q=8,P=11, TR= 88, TC= 75, piUpdated:= 13khi DN theo uui mc tiu tng li nhun =16=> pi= 16=>12Q- Q2-19=16=>Q2-12Q+35=0=> Q=7 , Q=5Khi doanh nghip theo tui mc tiu t l li nhun inh mc trn chi ph bnh qun =20%=>pi : AC= 1/5 (12Q-Q2-19)Q/TC= 1/5 (12Q2-Q3-19Q)*5 = 43+4Q5Q3-60Q2+99Q+43=0Khi doanh ngip theo uui ti a ha sn lng bn vi iiu kin khng lpi =0=>12Q -Q2 -19=0


22/23

Gi s 1 ngi tiu dng co thu nhp I =60.000 mua hai hng ho X v Y vigi tng ng Px = 1.300 v Py= 1.000. Bit hm li ch ca ngi tiu dng l TU(x,y) =X.Y1, Vit phng trnh ngn sch ngi tiu dng v minh ho trn th?

2, tnh M,MUy v t l thay th cn bin gia hai hng ho ny?3, ti a ha li ch, ngi tiu dng nn mua baoa nhiu hng ho X v Y? tnhtng lic ch ti a ? Minh ho ln th?4, Gi s hai hng ho khng i nhng thu nhp ca ngi tiu dng l 90.000.Hy xc nh im tiu dng ti u mi ca ngi tiu dng? dng th minhho?5, Nu thu nhp ca ngi tiu dng v gi hng ho X khng thay i cn gi hngho Y l 3.000 thi im tiu dng ti u mi thay i nh th no? Thit lp biucu hng ho Y v minh ho trn th?

pt g ns I=1300X+1000Y=60000 =>Y=60-13/10XMUx=(TUx)'=YMUy=XMRS=MUx/MUy=Y/Xti a ha li ch tha mn h sau MUx/Px=MUy/Py V 1300X+1000Y=60000=>X=300/13Y=30TU max=X*Y=300/13*30=900/13Khi I=90000 pt dg ns mi l Y=90-13/10Xtng t nh trn nh.im tiu dng ti u chnh l im m ti ti ha li ch.saua li tm TU maxkhi I=90000 Px ko thay i ,Py=3000,cng lp h tng t nhe'biu cu l P=1000 3000Q 45 15

bai 1.Cho hm cung,cu SP X: Qd= 40-P , Qs=10+2pTm gi v sn lng cn bng trn th trng.bi 2.Th trng sn phm X dang cn bng mc gi P=15 vaQ=20.ti im cnbng ny,h s ca cu co dn theo gi v ca cung theo gi ln lt l -1/2v1/2.Gi d hm s cung v ham so cu l hm tuyn tnh.Xc nh hm s cung vhm s cu th trng.bi 3 Vo nm 2006,do xut khu c go nn cu v go tng.Hm cu go bygi la: Qd1=110-10P.Xc nh gi v sn lng cn bng mi.

cu 1: cung cu cn bng nn ta c Qd=Qs=>40-P =10 + 2Pgii pt trn ta c : p=10, Q = 30.cu 2: pt TQ cu Qd = a +bP, Qs= a1+b1P, p=15,Q=20co gin cu theo gi ta c: Ep = (dQ/dP)P/Q)=-1/2=> (15b/20)=-1/2=>b=-4/3


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=>thay vo pt t c a=40vy pt cu :Qd= 40-4P/3tng t: ta cng c Qs = 4P/3cu 3:cng gii ging cu 1, Qd1=Qs10+2P=110-10p

P=8.3=>Q = 17.

Mt nh c quyn c hm tng chi ph: TC = Q2 + 6Q + 120. Sn phm ca nhc quyn ny c bn trn th trng c hm cu l: P = 50 - 0,1Q.1.Xc nh gi c v sn lng ti a ha li nhun ca nh c quyn.2. Nu mc tiu l ti a ha doanh thu th quyt nh ca nh c quyn s nh thno? Khi li nhun l bao nhiu?3.Nu chnh ph nh thu c nh 1 ln T=100 th gi c, sn lng v li nhunthay i nh th no?

a)iu kin ti a ha li nhun ca nh c quyn : MR=MCMC=TC'=2Q+6 v MR=TR'=(P*Q)'=(50Q-0,1Q2)=50-0,2Q=>2Q+6=50-0,2Q=>Q=20 , P=48b) ti a ha doanh thu TR max khi MR=0=>50-0,2Q= 0Q=250 , P=25 Khi : pi=TR- TC= - 57870=> Doanh nghip b lc) T= 100=> TC= Q2+6Q+220P= 48, Q= 20 nhng pi = TR- TC= 960-740= 220

gi la nm va qua l 2000$/kg; sn lng cn bng l 5000 tn. nm nay do hnhn nn nhng ngi nng dn trng la b mt ma. h s co dn ca cu v latheo gi c l - 0.6-thu nhp ca ngi trng la nm nay l tng hay gim so vi nm trc?- gi la nam nay tng ln 2500$/kg, sn lng la can bng nm nay l bao nhiu?- thu nhp ngi nng dn trng la thay i bao nh?

- thu nhp ca ngi trng la nm nay tng hay gim so vi nm trc?tra li:h s co dn ca cu v la theo gi c l|- 0.6|Q(nam nay)=2500*1.5/|-0.6|=6250(tn)-thu nhp nm nay=2500*6250*10^3=15625*10^6 triu ngthu nhp nm ngoi=2000*5000*10^3=10000*10^6 triu ngPhn trm thu nhp nm ngoi=10000*10^6/(15625*10^6+10000*10^6)=~ 10%Phn trm thu nhp nm nay=15625*10^6/(15625*10^6+10000*10^6)=~90%Vy thu nhp ca ngi nng dn nm nay tng hn 9 ln so nm ngoi.

Phuong Phap Giai Mot So Bai Tap Kinh Te Vi Mo

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