PHoNG- cD&PrJiNn YBx oB ruBu rRA HQC xi'u xAiu HQC 20L7 - 2018
iwOx' roAx z
Thdi gian ldm bdi 90 phtit, kh6ng k€ thdi gian giao di
r. TRAC NGHTpM (3,0 tli6m)
Ghi vdo til nm'cht mQi chir cdi A, B, C hofic D trwdc phwong dn ffrt bi ilfing'
C6u 1. Eon thric ndo sau ddy d6ng dang v6i don thuc -3xy2 ?
oB cnixn rrrtlc
A. -3x2y B. (-3*y)y C. -3(*Y)'
Ciu 2,Gi6 tIi bi6u thric 3*'y + 3y'x tqi x = -2 vd ! = -L ld:
'A. 12 - B. -9 C. 18
CAu 3. Thu ggn don thric P = x3 ! - 5*y' + 2x'y + 5xy' bingl,
A,.3x3y B. -x'y C. *'Y+l}xY3
Cdu
4.56 ndo sau d6y li nghiQm ctr,dathfic f(x)=?*+t?
3
;.? B. 1 6.-1 D.-?
3 "'2 2 3
Cau S. N6u AM li ducrng trung tuy6n vi G li trgng tdrn cria tam gi6c ABC thi:
!^)* = AB i. oi=?o* c. AG =1o, D' AM - AG
C6u 6. Cho mQt tam giitccan c6 dO dei hai cqnh li 3cm vi 21cm. Chu vi ctta tam gi6c d6 bdng:
A. 39cm B' 27 cm C' 45cm D' 46cm
rr. TIJ L,UA\ (7,0 tli6m)
CiuT (1,5 ili6m)
llong b6ng sau:
Di6m thi dua trong cic thingcira mQt
Th6ne 910 11 t2 12J45
Di6m 80 90 70 80 80 90 80 70 80
a) DAu t iQu ta git
bi L3p bing tAi s6. rim 19t cfia d6u hiQu;
c) Tinh dirSm trung binh thi dua ctra lop 7 A-
Cffu 8 (1,5 tli6m)
ChohaidathricP(,)=5x3_3x+7_xvitQ@)=_5x3+2x_3+2x_x2_2.
a) Thu gen hai da thric P(x) vd Q@);
b) Tim da thirc M (x)= P(x) + Q@) vd N(x) - P(x) - Q@);
c) Tim nghiQm cira da thttc M(x).- t'
cffu 9 (3,0 tli6m). Cho MBC co AB =3cmi AC = 4cm; BC = 5cm.
a) Chtmg t6 tam gi6c ABC vu6ng tqi A '
b) Vc ph6n gi6c BO(p. AC), tt D vd, DE L BC (A e aC). Chtmg minh: DA - DE;
c\ ED cht ,qn @i F. Chtrngminh: DF > DE'
/o
Ciu 10 (1,0 tli6m). Cho a,b,c ln cac tO tftUt kh6c 0. Tim c6c s6 thqc x,y,z l<hhc 0 thoi mdn:
xy - yz - ,* _*'^* y1* 11.
.
ay+bx bz+cY cx+az a'+b'+c'
-----AAt-'
Gido viAn coi hiAm oo khang giqi th{ch gi th€m'
D.-3xy
D. -1&
D. 3x3 y -10xy3
Ho vd t€n hec sinh: SBD..