so cD& ur viNn pHUC rnU$gc rHpr r,n xoav Ciu I. 't l. 3. Cdu II ri rnr. sAr n4crr LAN r NAM Hec z0tt-2012 on mu nnON roAlr L'Op ro- icnot o Thli gian ldm bdi 150 phrit, kh6ng t<e tnOi gian giao d6 __-_;__ ______ - 2. Tim m dd phuung trinh sau v0 nghiQm x-tit . x-3 I_ _., | _L x-l x cho phucrng trinh: zxz +Z(m+r)x+ mz +4nt+3=0 c6 2 nghiQm ",,x. Tim gi6 tri ldrn nh6t, nh6 nh6t cria bi6u rhric A:2( t * rl)_3*,*,. Gi6i phucrng trinh: Js,i + Jut = 4x -9 +zr,\f - 5, *2 (t i ciai he phucmg trinh: {o,l._rtiiiul:_;o=0 2. cho h6 phucng trinh: {.:T;::r=|!, rl_o*, Tim m ae ne c6 nghiQm duy nh6t ( x,y) th6a mdn r*t =z Cdu III. i. cho rarn gi6c a.BC, ,'€n BC l6y di6m D sao chorp =1ae. Gqi E Id di€m th6a mdn qEA+zEE +rfr :o . chrmg minh A, E, o driig rrang. - [ 1+cosC Za+b . 2. Nhfln dang tam gi6c biCr I ri" c = G;-F lo'@+c-a)=bo +co -ao CSu iV" Cho 2 sti thUc a,b th6a mdn a+b>2 Chring rninh rAng: at +b3 < aa +bo H9 va tdn thf sinh: S0 b6o,danh: Cdn b.6 coi thi khing.giirti thfch gi th€m. (s Toa;tu - lfJ,lh'D r/ BL: f zL I 4 4 ltL+b ,Fr<4 @-*; r. * qx' i) (r-a) : Jic t J) t tL /rz.x- + lt 4t-+J = zzt-;,t_ _h1k -LX_= J tL(n+z/ = 3 inl NQj; nt*e=a qd h=*2- lRsn /1t"a7r*1t/"V/V NA ru +-L 7tr xts a' lV 1>r da- ct* riui n I #, : L3 J Dt 1n t,t I J K d 2. irt, h, le {rnc, tu+r-z= -(na) \ - z : taL+4tu +3 2 A : a(trrrn - )x,)(L = J(\n ) V /\ = *(kM)'- fr- { <n 2h= flvt"'+VVn+l+ L 4 => - 3,w'"'* A-0 w, (n\+n+)) - f au t{rru -Jl l* * tl a -,/ )ru aH ttl, l8 ,r,, 4{r=, (rrt{ &= b{ t4s LJ, = - t t\' - Lorn- 47 'htt LI, - 4J 141 frr *t -r0I ^4 ,/ +4 "/ ; (5 r Y .,t u:t- .t/' -la* : G't LTUZA = "'6 .l dzrlV/rl LA:C t:Ua' {il," th**A,a 6rN{ll=o tLhtor,'-,1 xL?. L l- + V t-,1 l' ':;''' I = )rt-t {-L-4 -6-t t.1 t trq/ PTt t tt- r / t- ='t-*6 + 14 t'-t-(:0 Vo' t=J -t* co, , ,l/ T;P f= - -( ho, t= 3 ll Tr__L + ll r_a $ re +( u i-f +,6 7ct '!=) L *6 -Jl x_+4x.> ; 2L= 2_ =a14 I L L^4t(Le",\ ,/ &di'tr I 1 fd) yt' tr- -;)44 + [y'= o (,{ } 4n-+21! ttr- //=o Q b'-Aq F=u 4 tL-o ) (o,cr) o _ U,r.,:a';V€, tUi-rf1l C./* ya F*l,= y "3 Lo l- L =4J L 1=.j XL ,, L- 'J +'_ '4(xa, tlVrr-, *l[;; =j H,Gb + -tlffin, =;! ll 5r s tt+ z- : .{ * LL- '<)' J 6-2_*_z"o ) 3*-_:fr._t, = qt /*u, -l ) )(1__4qx_+ Eq P1- uj l\, ,x -, ) oz{- Etf or3'- q zs- CI)zi- ry2f Drt ,z \ t- rl ,ll , O = (144 -4[ra ,-f2 i),. = vt,(vt"-4)( wwt1.) {\ I)Y = t'' -l) [v,,+r1 2 -*r'" t l\^ ".t tqL rcI; P) I LL= &t- 4 luk=4 €r f l* (O Lq7r4 Le { tu' +.Qf vq't-, / ?_ + (tur.4 V= zwrS )v+'l J t" + ,, I I I I I I I I I lq,r I I I I I I D,; I i i i I i I i I I iVse I i I i iqi{ j I t lo7,i' d 'a? .y,t+wGC*r"/\?-+1.' t tq e (ar+oo) v;,7t , e, €,) td .*)) \=/ ,e At E/ t) t/*-{* o 'fii /sT I cd C,- Xli, C-' 4t aflc 4 tuna o d 4 4n4 <- i-a -b = A+be s A) Qa-{o tl qd'-b- &:k-[')L t-pa'4" Ja+ b +2a-(12 H4 2- ze-b J A -]a.e+o q_ 4{ttnc- , #* T )1b,.e> gj{rarte t' za+ L -:-€- +=J {:, A) &\- tr, =- trt f't =b A r+D c- ,t.t: 0iLf 'r4- vtI- € v "7 r^ I .[tt t tG .h I I l,,2) n* I I 6\ +b +bJtLr-:/ € ^ 2c v," {,, +b-L2/ 0 \ I *) frl t,*, rtt tt0; lr : ).c € ill (A-dl r l,) ( b -t) r a <b-t * (a ^4) * (b-a1> o \? (. rf( 6L{A{,{) +tb-,r )'(t\+ lr4l) 4 4i+-z7rD U) l)D otrr,*,r= q.L)i4)u Va. b'+ b+ *&l L:I w *6 ,hfu.u, Pa v?) lp-4 . pHUC rnU$gc rHpr r,n xoav Ciu I. 't l. 3. Cdu II ri rnr. sAr n4crr LAN r NAM Hec z0tt -2012 on mu nnON roAlr L'Op ro- icnot o Thli gian ldm bdi 150 phrit, kh6ng t<e