UBND riNH sAc NrNH of ruCer rRA cuAr LUqNG cufir NAna
sd clAo nuc vA oAo r4o Nem hoc: 20r.1-zutz
M6n: To6n tdp 9
Thdi gian: 90 phtflt (khilng kd thdi gian giao dd)
Ngdy thi: 20 thdng 4 ndm 2012
Bii 1 (2,5 didm)
1) Giei phuong trinh x2 + 2x-5 = 0.
2) Cho hhm sd y = (m - 1)x' (v6i m t 1). fim gi6 tri ctra m bidt dd thi cria him sd
trOn di qua didm A(-1; 2).
+1 1) Rtit ggn bidu thfc P;
2)Tinh gi6 tri cfia bidu thtlc P t?i x = 4.
BAri 3 Q,a didm)
MOt hinh chfi nhflt c6 chu vi bing 30 cm. Ndu chidu dii vi chidu rQng c&a htnh chfl
uh{t d6 ctng ting th€m 3 cm thi di€n tich cria hinh chfi nh4t d6 bing 98 cm2. Tfnh chidu
L dii vi chidu rQng cfra hinh chil nhflt dd cho.
t-
BAi 4 6,0 didm)
Cho dudng trbn (O; R) vi mQt didm A nim b€n ngoii dudng trbn d6. Qua didm A k6
duong thfing d vuOng g6c vdi OA, tren duorg thEng d ltty mQt didm M bdt H (M kh6c A).
Tt M kE c6c tidp tuydn MB, MC tdi duong rrbn (O).
, 1) Chr:ng minh tt gi6c MBOC nQi ridp duo. c du&rg trbn;
2) MO cit BC r?i H, chrlng minh OM.OH = R2;
3) Khi didm M thay ddi tren d, chrtng minh BC luon di qua mot didm cd dinh.
Bni 5 0,5 didm) Tim gi6 trf lon nhdt vi nh6 nhdt ctra bidu thrfic M = .rE+ 3 + G;.
Bei2 e,0didm) chobiduthric p =(+ *+'l ,(r-*l uoi x)0;x*e
\Jx -3 'lx+3) ( Jx +3/