Hertz Posted December 3, 2009 Report Share Posted December 3, 2009 Se da formula unei combinatii matematice.n C runde n e numarul total de selectii si r este numarul pe care il alegi.Formula de evaluare e: n! r! (n-r)!Care e raspunsul cand evaluezi aceasta expresie.17 C 10 - 30 C 12 + 50 C 3 Quote Link to comment Share on other sites More sharing options...
loki Posted December 3, 2009 Report Share Posted December 3, 2009 (edited) Clasa 12 algebra.17!/(10!*7!)-30!/(18!*12!)+50!/(47!*3!)de aici vine greul... poate revin EDIT mi-a dat 153,457.02(7) Edited December 3, 2009 by loki Quote Link to comment Share on other sites More sharing options...
Hertz Posted December 3, 2009 Author Report Share Posted December 3, 2009 Ecuatia e corecta , dar rezultatul e defapt -86454177Bravo! Quote Link to comment Share on other sites More sharing options...
loki Posted December 3, 2009 Report Share Posted December 3, 2009 de fapt17C10=8*11*13*17=19,44830C12=13*7*15*16*17*18*19*21*23*24*25*29=1,067,146,490,592,00050C3=8*49*50=19,600-1,067,146,490,379,952uh ma pierd la calculatul termenilor. Ideea problemei ca pui 50!/47!=48*49*50 si apoi elimini termenii din fractie ... Quote Link to comment Share on other sites More sharing options...
tw8 Posted December 21, 2009 Report Share Posted December 21, 2009 Ai gresit la C(30,12). Daca tii neaparat sa faci prin metoda asta, atunci C(30,12) ar fi 3 * 7 * 13 * 19 * 23 * 25 * 29.Totusi, e mult mai la indemana sa folosesti WolframAlpha pentru asta sau chiar calculatorul de la Windows .Rezultatul este, dupa cum a spus si Hertz, -86454177. Quote Link to comment Share on other sites More sharing options...