g* -:i pnAru emur*G TEXE TFEti *)AE ffiSC (*qt 2) na$ru T*€I: T$AN Ky thi rcgdy:27183I201i T'hbi giarc ldm !;di : 180 pk*t fHa rAr cA eAc rmisrnr-i (lau I (Z,fi diArn) Cho y=xr-2(m+i )x2+mr+nr+3 (l;, l) Khao sdi & vC d0 thi lrirnr:,0 nr=O 2) ain sir dd thi (1) cit ox rtri + diem c6 hoirnh xljrl + irr-t1 +.r1.\:.1 +.r).tr +,y,_rr Cau a- ^\ #E m*,&,jq* UN{;'rertry {,.T"f,}.F[ sd +q' - Hq;ri zq}4 F-fr'F'F{ANF{ HGHI ilT : G,$,22,453 3{t - {},# "2:2# t E F 2# TiR r ,-r., { dQ x,, x2, xr, xo chfng minh rang: $ II {2,t} diAm) II Ciai phLr,rrlg llinh : sirr' l.r.uti5g.v+sinr3-u= lrin''t.rin 9" 222 ti 2) Girii he iren iP,: _r I ,ll l1l 1-.1 '.= rffi 4,rr - 1,' lJx 7r\ srnl tj a] /a {r& 4q$ ) {lnu ttl {l.S didrn} Tinh i - I J {) € \ | \ ! t/ (o z\ srnl -+ l? al d\ I ft,, w,i u rty# { -s rS ,, tR T$ & -'*+ N S"C & Cdu cd cirirrr cil-Ldng cao FI ke tr.lr A' 1) trung didm BC AC=2a A.'A=2a, tfnh khoring c{ch gifra A'A & BC Cau V {1,0 di6m) 6i = 600, AB=a Gidi phrrong ri'inh: r,f,+qI \' | ^[x1 pniix nrEuo ( rhi sinh chi duoc lirm phdn A hoac phdn B ) A.Theo chuong fninh chudn Ciu Vila (2,0 diiim) i)Trong h0 rOy cho hinh binh hlnh ABCD c6 C(-4,-5) duong cao (AH): x+Zy-2=A.dudng ch6o (BD): 8x-y-3=0, tim toii clo A, B, D 2)Trong h0 Oxyz viet phuong trinh mat phing (Q) song song mht phing (F): x+y-22+3=0 cho (Q) cat hai dudng thlng 1ct,): {EF *S o.ip €b ,f ,rflt *'*J IV (1,0 diilmr Lang tlu ABC.A'B'C' ! =':tI = 1e(d,): {-,1 = v :}-= I i theo doan AB=9 t"-" (A ed,,13 d, ) = Cflu VIIa (1,0 didrn) Girii phuong trinh: logi -r + (.r - l2)log,x + I I -.r = B.Theo chuong trinh nAng cao Cau VIb (2,0.tiem) 1) Trong he xOy cho hinh binli hanh ABCD c6 B(1,5), dudng cao (AH): x+2y-2=0 gi6c i-n lii x-y- l=0 'fim roir A, C, D r @,+ 2)Trong h0 Oxyz ,, iet phrLcruu rrlnh mat phang (Q) cdu (s): x2+y2+22 -2;0 € I l,S =2(nt+ l) > in > I lP = rt2 + m+2> rr,/, h, ttghf*;"""g Pha" btcJ;rfr^ (r), kLt dilr, J-." trinh xl =1, vi xt =tz + xr +.f,' r.Y, *-J+ =0 Ta l4i c6: (x, + \ +x, + xu)t -2(xtx, + tN,tx3 + xtx4 + x)x3 + l,x4 + x.,xa) = ri + + xi +-"ut ) G" i I I I I I 3A I I iiI l- 0.7lt =0-ZT>A=T 2d I Pt e (L -cos4x)cos6x+ I -cos6x = rin*22rinI 1- l cosl0x) = jt.otr-cos10,r) cos2x+cosx-2 f,korzr+ 2cos2 x+cosx-3 '- D+ IL - a.25 1- lr' - y'+9 l_-, xz+{v=.y2 L- -7 IJJ , t^ - y It^ l-6x'+ n k2 lf) k e COSx=1 -g 12x = =3 v' + v ) 0.5 nt - 6xt +l2x -B = y3 +3y2 +3y +l ti 0.5 L:-, ilAL t -= r l - I rhi i - f:ln rr 2tlr =ZJt+rl,r; t- i)dt:J{ tcos2 t -')\dr ]+ | ! stil/ tL -') L 11 - /L - 72 Ir r uol -' K la irturgeli6m cua ACthitirgidthi€tsuy BC:a-/i,Znc:900=*, HK,llC.l{A'dli m6t vu6ng g6c n€n xem I!(CI,0,0),AFI ='[AE + THt f; l; L?!/ _, r -, L-,,,,0trJ \ : , u), 0) e {}x 2, (t.25 ?_ t: KQ.;,a) eo1,; o(+ *Tu * ,4 B B'(0, *,=l',' t / I t lt t+(0.J,2) =ri-[,'r",,?cl= L I " lrrc1L!!,o,as N,f Xem ilaa'c'r'1 = (0, 3,2) => tl 4.7 3y +22 = =+ d:(AA", BC) = d(A, BB C C') : -:* vti 1.t EK: x >2.Taco pt€> r : Vx,+91-10=Vx- Z-r+x= -g€-#-+91 +i0=-Q tJx-2+l,+(-r-3)(x+ j) "lxt 0.5 zd ltc diqua di€m C(-4 , -5) vir vu6ng gbc voiu aa (-2, i) = c6 phuorng trinh -2(x +4)-t-(y+5)=0= I toa dQ B la nghiCm I hQ l-zr+y-3=0 l+ \- L8t-y-i=0 B(1,5) BC Al2 -,) = AB t(I tt,{t}.; Il_ , - o,!tf)e 8x - t' - ] = i-) =,[!,,,\ n - c; m = fiJj x, phuorrg trinh tro thirnh: rt * (x-12)t+11-r=0, a+b+c=0 suy hodc log, -r=1hcdc log,x=11-x Ek: x > DAi / = log, l log,r=i=x='l(nhan) |* t- * l"g, -r - I I -x=)x vib I2d | I =S lirnghi0m nh6t vi VT d,3ngbi6n VP nghich bidn eC qua ciiem B(1,5) vA vuong goc v6'i tt.-,,(-2,1.=+ BC -Zlx-l)+(y-5)=0= Itoa a0 c ld righi€m n* f-rr+v-r=o " -> C(-4,-5| i, I trl, = u lcophu.rngtrinh I Cqi ,a la diim dOixrmg cuaB quaphAn giitc I j*Onggocvoi {"-'-:=^o=0= lf"-y-I=0 Rt'r1-l DY< :X,/c D ^' lri 1(.x-1)+l(y-5)=0+ tgadd KlenghiQmh$ xf1,trl= '2'2' A(6,0) Do A=C.4 r-tAH ndn toadol tanghiQm hQ =A(4.-t) Ll"?41-o n=ID=D(-1,-ll) I VIIb Q.25 tltm I(7,-2,3), fi = (Q) co dang 2x +l -2y -J 1d x* yi m+9 =12 m+9 = -1'2 _-r, r:l "l-l f"' ) +9 = m=3 m=-2I -i (Q):2x*2y+z+3=A (Q):2x -2y + z -21= 0.5 A (x,veR)' regt=.p.t -2(* - !i) = -3+6i Il-Y. j 0,5 + z + m = 0, d{l,Q) = 12+1+3+n',1 I_a ., Gi6 sit z = i 0.5 6=o=o ll'-zv' (,S) c6 0.25 x-3t-l=O(d),BA n d = K (KB) rii qua B vi u,r(l,l) =)(Kts)cdphucmgtrinh: I A'^ * , {, 'tt) _ I /F-i 71) 0.5 l-3 lx/- €>1 ... _1- - -i- _ lzv=s A4 t1 12x-3)2 L:r' -l2r Iv^' Er;.])/ ll" l rlx" +y- =2x-3 0.5 lY=3 t1: =0 =l'l+ltl' +lrl' =5+25+125 =155 - Thi thfi dot nsdy 3010412011 Thi thit rlrtr ntdi nadv I6106120l I 0.5... 6xt +l2x -B = y3 +3y2 +3y +l ti 0.5 L:-, ilAL t -= r l - I rhi i - f:ln rr 2tlr =ZJt+rl,r; t- i)dt:J{ tcos2 t -')dr ]+ | ! stil/ tL -') L 11 - /L - 72 Ir r uol -' K la irturgeli6m cua ACthitirgidthi€tsuy... I hQ l-zr+y-3=0 l+ - L8t-y-i=0 B(1,5) BC Al2 -,) = AB t(I tt,{t}.; Il_ , - o,!tf)e 8x - t' - ] = i-) =,[!,,, n - c; m = fiJj x, phuorrg trinh tro thirnh: rt * (x-12)t+11-r=0, a+b+c=0 suy hodc