ICEBREAKER101010 Posted November 21, 2010 Report Share Posted November 21, 2010 Invata matematica online.MathPDR - matematica onlineHave Funk! 1 Quote Link to comment Share on other sites More sharing options...
Depanatorul Posted November 21, 2010 Report Share Posted November 21, 2010 mane lasane ) Quote Link to comment Share on other sites More sharing options...
Smks Posted November 21, 2010 Report Share Posted November 21, 2010 e foarte bun site-u deoarece de ex mie nu prea imi place matematica dar trebuie sa o invat si cum nu am invatato trebuie acum sa o invat pt capacitate sunt kid Quote Link to comment Share on other sites More sharing options...
c0smyn Posted November 21, 2010 Report Share Posted November 21, 2010 Foarte bun Quote Link to comment Share on other sites More sharing options...
Printu2008 Posted November 21, 2010 Report Share Posted November 21, 2010 Destul de usurele...e ok siteul Quote Link to comment Share on other sites More sharing options...
demon_zone Posted November 21, 2010 Report Share Posted November 21, 2010 my opinion...usefull Quote Link to comment Share on other sites More sharing options...
Cr3ativ Posted November 21, 2010 Report Share Posted November 21, 2010 Foarte folositoare lectiile. Cel putin pentru mine, care dau bacu' anu' asta Ms pentru pont Quote Link to comment Share on other sites More sharing options...
qbert Posted November 21, 2010 Report Share Posted November 21, 2010 Thanks alot,chiar aveam nevoie de asa ceva! Quote Link to comment Share on other sites More sharing options...
flaviusone Posted November 21, 2010 Report Share Posted November 21, 2010 Foarte util , abea astept sa bage parte de structuri algebrice de a 12-a XD Quote Link to comment Share on other sites More sharing options...
H2K Posted November 21, 2010 Report Share Posted November 21, 2010 Bogdaproste sarumana nice thx Quote Link to comment Share on other sites More sharing options...
just-for-funn Posted November 21, 2010 Report Share Posted November 21, 2010 D-Zeu sa`ti dea sanatate! Quote Link to comment Share on other sites More sharing options...
Silkie Posted November 21, 2010 Report Share Posted November 21, 2010 Mersi frumos. Quote Link to comment Share on other sites More sharing options...
Oust Posted November 22, 2010 Report Share Posted November 22, 2010 sa traiesti !!! Quote Link to comment Share on other sites More sharing options...
blackrunner1911 Posted November 22, 2010 Report Share Posted November 22, 2010 mersi de informatii chiaar ma ajuta Quote Link to comment Share on other sites More sharing options...
dma Posted November 22, 2010 Report Share Posted November 22, 2010 mersi mult Quote Link to comment Share on other sites More sharing options...
Dokil Posted November 22, 2010 Report Share Posted November 22, 2010 Se vede ca Clujul este capitala culturala:> Quote Link to comment Share on other sites More sharing options...
crs12decoder Posted November 22, 2010 Report Share Posted November 22, 2010 super belea... . Folositoare, ce nu poate sa-mi explice dirigu(profu de mate) inteleg aici perfect. Daca mai stiti site-uri de genu' postati. Quote Link to comment Share on other sites More sharing options...
sado Posted November 22, 2010 Report Share Posted November 22, 2010 ps: ban Depanatorul ca e un idiot. si asa vreti voi sa fie forumul retard-free.@ pax +ON:oricum aveam nevoie de ceva ore suplimentare ) dar sper ca nu va m-ai fi nevoie Quote Link to comment Share on other sites More sharing options...
SympleBoy22 Posted November 22, 2010 Report Share Posted November 22, 2010 Are cineva cont pe Mathway? Quote Link to comment Share on other sites More sharing options...
radupoe Posted November 22, 2010 Report Share Posted November 22, 2010 Am vazut vizite de pe acest forum si am inregistrat un cont.. Pentru cine cauta structuri algebrice, tocmai lucram la proprietatile de baza ale legilor de compozitie, deci urmeaza sa apara.. Daca ati avea ceva exercitii anume care doriti sa le vedeti postate pe site, poate va pot ajuta. Quote Link to comment Share on other sites More sharing options...
demon_zone Posted November 22, 2010 Report Share Posted November 22, 2010 Exemplu, legi de compozitie:M=(1,?)x*y=2xy-2x-2y+31. Demonstrati ca legea este asociativa: (G1)G1: (x*y)*z=x*(y*z)2. Demonstrati ca legea are element neutru: (G2)G2: e*x=x*e=xe = element neutru3. Demonstrati ca legea are elemente simetrizabile: (G3)G3: x'*x=ex' = inversul lui x4. Demonstrati ca legea este comutativa: (G4)G4: x*y=y*xRezolvare:1. G1: (x*y)*z=x*(y*z)notam x*y cu A. Si inlocuim ca in x*y=2xy-2x-2y+3. Uite:A*z=2Az-2A-2z+3A era x*y, adica A=x*y=2xy-2x-2y+3, si pe A il inlocuim cu cat e egal x*y, asa:A*z=2(2xy-2x-2y+3)z-2(2xy-2x-2y+3)-2z+3A*z=4xyz-4xz-4yz+6z-4xy+4x+4y-6-2z+3A*z=4xyz-4xy-4yz-4xz+4x+4y+4z-3Asa facem si cu x*(y*z)notam y*z cu B. Si inlocuim ca in x*y=2yz-2y-2z+3x*B=2xB-2x-2B+3B era y*z, adica B=y*z=2yz-2y-2z+3, si pe B il inlocuim cu cat e egal y*z, asa:x*B=2x (2yz-2y-2z+3)-2x-2(2yz-2y-2z+3)+3x*B=4xyz-4xy-4xz+6x-2x-4yz+4y+4z-6+3x*B=4xyz-4xy-4xz-4yz+4x+4y+4z-3A*z=x*B ? Dax*(y*z)=(x*y)*z ? DaDeci rezulta ca legea este asociativa.2. G2: e*x=x*e=xx*e=xNu facem altceva decat sa inlocuim pe e cu y in legea data:x*e=2xe-2x-2e+3cum x*e=x, avem:2xe-2x-2e+3=x*intodeauna, trebuie aflat doar ce se afla dupa exista, adica e. Si nu x-ul! Multi fac greseala asta.2xe-2e=x-3+2xDam factor comun pe e:e(2x-2)=3x-3Dam facut comun pe 2 din prima ecuatie si pe x din a 2-a:2e(x-1)=3(x-1)si avem:e=3/2Element neutru.3. G3: x'*x=eLa fel. Inlocuim cu x' in legea intitiala:x'*x=2x'x-2x'-2x+3Si cum x'*x=e, unde e=3/2, avem:2x'x-2x'-2x+3=3/2La fel. Se afla doar ce se afla dupa exista. In cazul asta, x' .2x'x-2x'=3/2-3+2xx'(2x-2)=(3-6+4x)/2Scoatem factor comun pe 2 din prima ecuatie:2x'(x-1)=(4x-3)/24x'(x-1)=4x-3x'=(4x-3)/4(x-1)Ce face asta? Calculeaza elementu inversu pentru un numar din legea asta: 6'=21/20. Asta e inversul lui 6.4. G4: x*y=y*xx*y=2xy-2x-2y+3y*x=2yx-2y-2x+32xy-2x-2y+3=2yx-2y-2x+32xy-2x-2y=2yx-2y-2x2xy-2(x+y)=2yx-2(y+x)Lege comutativa, deoarece inmultirea si adunarea sunt comutative.Source: my notebook. Next time, mai bine scanez.. pfff Quote Link to comment Share on other sites More sharing options...
dragosh1904 Posted November 23, 2010 Report Share Posted November 23, 2010 wow asta e super multzam ai vreo leg cu siteul?eu mai foloseam Khan Academy^^^chiar azi am facut Quote Link to comment Share on other sites More sharing options...
radupoe Posted November 24, 2010 Report Share Posted November 24, 2010 Am adaugat proprietati ale legilor de compozitie (pentru cine a cerut) si inca o integrala rezolvata prin schimbare de variabila.. Quote Link to comment Share on other sites More sharing options...
dragosh1904 Posted November 25, 2010 Report Share Posted November 25, 2010 Am adaugat proprietati ale legilor de compozitie (pentru cine a cerut) si inca o integrala rezolvata prin schimbare de variabila..daca poti pune la integrale nedefinite ceva despre relatia "leibniz newton" ps imi poti da pm cu un id de mess?numai bine multumesc! Quote Link to comment Share on other sites More sharing options...
