Đang tải... (xem toàn văn)
SANG TAD Bill T O J l N i l I I I BAI TDAN BAN DAU VtBATOiNG IHOC NHAM BtNlUYlNTUBUYDPGlAP SANGTAD CHD HOC SINH TRDNG HOC PDOTHONG O ThS N G U Y I N S O N HA" R6n luy^n hi duy d ^ l§p vd sdng Igo cho[.]
SANG TAD Bill TOJlNil III BAI TDAN BAN DAU VtBATOiNG IHOC NHAM BtNlUYlNTUBUYDPGlAP.SANGTAD CHD HOC SINH TRDNG HOC PDOTHONG O ThS N G U Y I N S O N HA" 6n luy^n hi d ^ l§p vd sdng Igo cho aj Vi X> 2n6nxfx-;)(x-2)>0=>A-B>0=> hpc sinh (HS) Id m$t nhOng nhl^m vi, A>B quan trpng dgy hpc mdn Todn bl X6t dSu Clio bllu thiic xlx-](x-2l: trudng phd' thdng Phfin Idm nhOng bdl todn (BT| X -co KO pha llidng hl^n noy Id BT cd kS't lu^n rS rdng, X + - + + ygu cdu chvng minh m^t k^t qud ndo dd ho$c x-1 - + + tim m$t dd'l tupng c\f th^; tu nhihig BT dd, gido x-2 - - vlSn (GV| cd thi thoy dd'l cdch phdt bllu d l duo >t(x-lXx-2) - + - + ro BT mdl B^t ddng ihljc (BDT) Id m^t dpng todn tllm long nhllu khd ndng phdl trlln tu cho To cd: v6l X e {0;1;2) thi A-B > => A=B: v6l ngudi hpc Bdi bdo trinh bdy m^t so' cdch sdng i s ( ^ ; ) u ( l ; ) thi A-B < => A => A>B r^n luv^n tu d$c l$p, sdng too cho HS d trung Nhdn xSt: Trong qud Irlnh x6t dd'u cOo bllu hpc pnd' ttidng thiic A - B, HS cd thi tv dS xud't cdc dllu kiSn GV gie(u di phdp todn cda BDT, yiu c&u khdc doi X vdi vd duo ro kit qud mdi HS so sdnh gid trj cOa cdc bilu ihuc, sau dd VIdu 2: BTban dau: Chiing minh rfing: aix-1 HS tv thay d6\ dllu ki^n cua BT d l Hm kit > a+b, v6l^a,b > h qud mdt BTmdl: Cho cdc sd thi/c o, b> L BT han ddu: Cho A, to cdc bliu ihuc chiia al So sdnh hal bleu thiic M = ab+ vd b/6i ChOng minh BDT A > B N = a+b _ Trong BT ban ddu ndy, bllu thi>c cdn chung bj Nlu thoy doi dieu kiSn dd'l vol cdc so' a, b, minh du