so crAo DUC vA EAo rAo HA Ner pB rnr rHrJ DAr Hec EOT r NAirn zOt t TRIIONG THpr crIU vAx nx M6n Torin - xtr6i,q,. Thdi gian ldm bii: 180 phft, kh6ng te tnOi gian giao dA" PA ttri gom o1 trang. I. PHAN cHUNG cHo rAr cA cAc rui sINH 1z,o aiom; Cfiu I1Z,O Oi6m1 Cho hdm s6 y = x' -3xz +1. 1. Kh6o s6t sy bitin thiOn vi vd d6 thi (C) ctrd harn si5. 2. Chrmg minh r[ng mdi ti€p tuydn ctra (C) chi ti6p xirc vdi (C) tar dirng mQt di6m. Cfru II (2,0 tti6m) 1. Giei phuong trinh 9'io" * 4.gcos' *= 13 + n"o"z"+)-3oo'2'. lx+ Y =g 2, ciaihephucrngot* {67* +"[y=.9 =1g (x,veR)' Cflu IItr (1,0 ili6m) Tfnh tich phan / ='1bt-6*. ix' CAuIV(l,0ili6mlChohinh ch6p S.ABCD c6d6yldhinhvudng c$th a, SAL('LACn)vd SA=a. Ggi A',8',C'vit D'lanluqtld'trungdi6mctra,SC,SD,SA vd SB. Chimgminhrdng AA',BB',CC'vit DD'ddngquy;Tinhth6tichctrahinh cb6p S'.A'BtCtDt theo a,v6i ,S'htamcuahtnhvu6ng ABCD. Cau V (1,0 tliGm) X6c dinh m saocho xa -2x3 +Q**l)*' -2mx+m' -4>0, Vx e [-f1] II. PHAN mtNC (3,0 rli0m). Thi sinh chi iluqc ehgn mQt trong hai phAn (phin A ho{c phAn B) A. Phin A (theo chucrng trinh ChuAn): Cfiu VI.a (2,0 ili0m) 1. Trong m* phang tqa dQ Oxy, cho hinh vu6ng c6 mQt dinh l(- l;2) vd mQt duong ch6o nim trOn <ludrng thing c6 phuong trinh 2x - y -l = 0. Tim tea d0 c6c dinh cdn lpi cira hinh vu6ng. 2. Vi6t phuong trinh m{t cAu (C) c6 €m thuQc duong thi"g (A) c6 phuong trinh ( J*-Y*z=0 lZx+Y+22-l:0 vitit5p xric voi hai mft ph&ng (a): 2x +2y - z + 6 =O va (p) : 2x +2y - z-6 = 0. Ciu VII.a (1,0 tliSm) Cha z,z, ldhai nghiQm phrlc cira phucmg trinh z2 -22 +5 = 0. Tinh gi6 tri cua bi€u thirc P =|"?l*lt:l B. PhAn B (theo chuong trinh NAng cao): CAu VI.b (2,0 tli6m) 1. Trongmatphingtqad0 Oxy chodubngtrdn(C): *2+y2-4x+2y-5=0.JimndeduOngthing , d,i x - my=O cit ducrng tron (C) tar hai di0m A, B phinbiQt, sao cho d0 dii do4nlB nh6 nhdt. 2. Trong khdng gian tqa dQt Oxyz cho cdc di6m ,4(1;01;, A(;U0) CQ;l;*l) vd mit pheng (o) cO phuong trinhr + y + z-1 : 0. Tim toa d0 di6m M sao cho khoing c6ch tit M d6n (a) b6ng khoang c6chtir M d6nm6iei6m A,B,C. Ciu VII.b (f ,0 di€m) Tim s6 phrlc z ,Aiet 2 =*! H6t- ,4* . n'd nn J $,; nfun'. V' ut -fft''o-n " Hq vi t0n thi sinh: ; S6 teo danh: . 1z,o aiom; Cfiu I1Z,O Oi6m1 Cho hdm s6 y = x' -3xz +1. 1. Kh6o s6t sy bitin thiOn vi vd d6 thi (C) ctrd harn si5. 2. Chrmg minh r[ng mdi ti€p tuydn ctra (C) chi ti6p xirc. nim trOn <ludrng thing c6 phuong trinh 2x - y -l = 0. Tim tea d0 c6c dinh cdn lpi cira hinh vu6ng. 2. Vi6t phuong trinh m{t cAu (C) c6 €m thuQc duong thi& quot;g (A) c6 phuong. tri cua bi€u thirc P =|"?l*lt:l B. PhAn B (theo chuong trinh NAng cao): CAu VI.b (2,0 tli6m) 1. Trongmatphingtqad0 Oxy chodubngtrdn(C): *2+y2-4x+2y-5=0.JimndeduOngthing , d,i