Bllei UASVM, Horilre 65(/008 pissn 1843-554; eissn 1843-5394 DERIVING THE DEMAND CURVE ASSUMING THAT THE MARGINAL UTILITY FUNCTIONS ARE LINEAR Crii C. MERCE Uiveriy of Agrilrl iee d Veeriry Mediie Clj-Npo, ere@yhoo.o Keyword: ded fio, eqirgil priiple, lier rgil iliy fio Ar: Thi pperwork derive he fio of ded depedig o prie ig h he rgil iliy fio re lier. The i ide i h we derive he ded fio rig fro he eqirgil priiple. Srig fro he eqirgil priiple d fro he dge eqio d ig h he rgil iliy fio re lier we derive he ded fio. INTRODUCTION The eooi lierre expli h ewee ded d prie exi ivere oeio. More h h, hi oeio i deored qliively rig fro he eqirgil priiple. Thi pperwork rie o derive qiive oeio ewee ded d prie rig for he eqirgil priiple, ig h he rgil iliie re lier fio. MATHERIALS AND METHODS A i i kow i eooi heory, he oer xiize ol iliy whe he followig odiio re verified ileoly: ( ( (... (1... B ( Where,,, re o egive d re,,, o egive. A oe oerve, he eqirgil priiple led o he followig ye of eqio: ( (... ( (... B 0
1 The ye ove h eqio d kow. Fro he eqio, -1 eqio rel fro he row of eqirgil eqio, d he -h eqio i he dge eqio. Whe rgil iliy of eh good i lier fio, he ye ove eoe lier ye of eqio wih kow. If he rgil iliy fio re lier, h hey y e expreed i he followig er: d 0 d 0. d 0 Uder hee odiio he ye of lier eqio wih kow ove e wrie der he followig for: B...... The olio of hi ye of eqio i eier h he geerl e of ye of eqio wih kow. Thi olio e doe i he followig er: Oe expre fio of fro he fir eqio, fio of fro he eod eqio, d o o il he l eqio where we expre fio of. Oe reple,,, i he dge eqio, relig lier eqio wih oe kow -. Solvig hi eqio we oi. Oe reple i he fir -1 eqio d hi er oe oi he vle of,,,. Oe peil e whih y pper i h i whih oe or ore of he qiie,,, re egive. The iiil odiio i h ll qiie re o egive. Le ppoe h oe of he qiie whih verify he ye of eqio i egive. Le ppoe h hi i. I hi e we will ig o vle zero d we will olve he ye of -1 eqio wih -1 kow whih follow: B......
The olio of hi ye will e doe loge o h wih eqio wih kow d will led o he olio,,,,. RESULTS AND DISCUTIONS Now we will derive he ded rve for good i wo oree e i whih we ke io oiderio oly wo good. Fro he hpe poi of view, he grphi of ded for good i he e idiffere how y good we ke io oiderio. The heil ll i loge eoe ore lorio. Exple 1 ( 100 ( 10 3 I preer whih y ke poiive vle 9 ; B 10 The ye of eqio whih rel fro he eqirgil priiple i: 100 10 3 9 9 10 Wih kow d The olio of he eqio ye led o he followig olio: 700 0 54 40 300 160 54 18 150 54 63 0 54 The odiio of o egiviy for he qiy led o: 18 150 0 54 18 The odiio of o egiviy for qiy led o: 63 0 0 Whih i eqivle o: 54 63 0 Whih i verified for eh ee: 15 4 63 79 0 The grphi of ded for good depedig o prie i he followig:
Exple ( 100 ( 10 3 I preer whih y ke poiive vle 1 ; B 10 The ye of eqio whih rel fro he eqirgil priiple i: 100 10 3 1 1 10 Wih he kow d Solvig he eqio ye we oi: 4800 360 96 10 100 880 3 ( 96 40 3 10 96 10 4 40 96 The odiio of o egiviy for led o: 40 3 10 0 13, (3 96 3
The odiio of o egiviy for led o: 10 4 40 0 Whih i eqivle o 96 10 4 0 Whih i verified for [ 0;4] [ 6;13, (3] For [ 4;6] oly oe good will e prhed, good. The ded fio for good will e: 10 The grphi of ded for good fio of prie will deped o he iervl whih oi. I will e he followig oe: CONCLUSIONS OBS. I order o oi grphi of hi ype oe h o oplih he followig odiio:... B Thi odiio y h if we lloe he dge for ll he oher good exep good we will o reh o he ol ifio of ll oher eed, eed h re ified wih good,,,. A we ee i oh iio ook exple, he fio prie - ded i dereig. I he eod e he idividl ded fio i o derivle o he eire doi of defiiio. REFERENCES 1. Slo, Joh, 1998, Eooi, reie Hll Eorope.. MCoell, Cpell, Bre Sley, MGrw-Hill Irwi, 005. 4