UBND TiNH THAI NGUYEN
so GrAo DUC & DAO TAO
on cniNn rutlc
rY rnr LAp EQr ruvf,N nr/ rnr HQC srNH GroI
euoc GIA LoP 12 THPT NAvt HQC 20Ls - 2016
vrON: ToAN uQg
Thdi gian: 180 philt (Kh6ng k€ thdi gian giao dA)
Ngny thiz24ll0l2015
(Dd tni gdm c6 01 trang)
th6a mdn: x' + y' +l chia h6t cho Zxy +1.
Bnilz(4diAm)
cho c5c s6 thgc duong a,b,c th6a man abc = 1 chimg minh rirg,
ao +b'+co +a+b*"*]9 - * ,2b , a-29 'g'
Bdri 2: @ diem)
Giai h9 phuong trinh Sau:
Biri 3: @ diA@
Cho ducrng trdn (O) va mQt di6m A n6m ngodi dudng trdn Tir di0m A ke cdc ti6p tuytin AB,AC t6i (O) (B,C ld cdc ti6p di6m) Gqi E,F hn luqt ld trung di6m cua AB,AC; D ldmQt di6m UAt t<i tr€n EF Tir D k6 titip tuy6n DP,DQ t6i (O) (P,8 ld c6c ti6p di6m) Gia st P@ c6t str tqi M chrmg minh ringm =90o
Biri 4: @ diAm)
Cho c6c sO nguyOn dmong x,y
ChrmgminhtSrg: x=!.
Biri 5: @ dilm)
,i.
v6i c6c s6 nguyCn ducrng o,,b,c thuQc dopn [t;zots], h6i c6 t6t chbao nhi6ubO (o,b,c) sao cho o' +b3 +c' chiahtit cho g?
16* * s)''lrx n - 2y -3y' = o
\_
[y+J, -r!2x'+4x-23