;{ '-; xCuyeN TRTIOT\G THpr cHUyEN sd CoeoET THAI (Haong ddn chtim gi* HIIONG nAN CnAvr THI xnAo sAr cnAr LUQNG vAo LOP 10 li ruON vAr Ngdy thi: 15 thdng ndm 2016 Thdi gian ldm bdi: 150 Philt ro trang) (1,5 tli6 m Ciuu 1: (1 DIEM NOI DUI{G Y AB: 10km a) (1 d) vl = AYr BY2 10km lzknlh vz= 4kmlh C Gi6 su hai ngudi gdp tai C nhu hinh vE Gqi t ld thli gian tir hic 7h sSng t6i hic hai ngudi g{p T6i luc g4p thi ngudi di xe dpp vd ngudi di b0 dA dopn ducrng tucrng img ld: t, = o_r^= ,,., (, ) Sz= BC =rz.t Ta c6: sr - sz -l\km (2) Giai h0 (1) (2) ta tim dugc t: t,25 grd K6t lupn: Hai ngudi gap nhu, lir" gid 15 phrt Vi tri g{p c6ch A dopn AC = l5km + a) (0,5 d) d di dugc Tru6c hai ngudi 0,25 0,25 0,,25 0,25 gEP nhau: d -10 -8r;(r