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S gio dc v o to thi chuyn cp lp 10 tnh ngh an
S GIO DC V O TO THI CHUYN CP LP 10 TNH NGH AN
TNH NGH AN NM HC 2006 - 2007Bi 1(2)
Cho biu thc:
a) Tm iu kin v rt gn P
b) Tm x P>0
Bi 2(1,5)
Trong mt k thi tuyn sinh vo lp 10 hai trng THCS A v B c tt c 450 hc sinh d thi. Bit s hc sinh trng tuyn ca trng A bng 3/4 s hc sinh d thi ca trng A, s hc sinh trng tuyn ca trng B bng 9/10 s hc sinh d thi trng B. Tng s hc sinh trng tuyn ca hai trng bng 4/5 s hc sinh d thi ca hai trng. Tnh s hc sinh d thi ca mi trng.
Bi 3 (2,5)
Cho phng trnh: (1)
a) Gii phng trnh (1) khi m = 1
b) Tm m phng trnh (1) c hai nghim phn bit
c) Gi hai nghim ca phng trnh (1) l x1; x2. Hy xc nh m :
Bi 4 (4)
Cho na ng trn tm O ng knh AB = 2 R. M l mt im bt k trn na ng trn sao cho cung AM ln hn cung MB (M B). Qua M k tip tuyn d ca na ng trn ni trn. K AD; BC vung gc vi d trong D,C thuc ng thng d.
a) Chng minh M l trung im CD.
b) Chng minh AD.BC = CM2.
c) Chng minh ng trn ng knh CD tip xc vi ng thng AB.
d) K MH vung gc vi AB (H thuc AB) Hy xc nh v tr M din tch tam gic DHC bng 1/4 din tch tam gic AMB.
S GD&T NGH AN K THI TUYN SINH VO LP 10 THPT
NM HC 2007- 2008
Mn thi : Ton ; Thi gian 120 pht .
Phn I . Trc nghim ( 2im ) .
Em hy chn mt phng n tr li ng trong cc phng n ( A,B,C,D ) ca tng cu sau ri ghi phng n chn vo bi lm .
Cu 1 . th hm s y = 3x - 2 ct trc tung ti im c tung l
A. 2 B. -2 C. 3 D. .
Cu 2 . H phng trnh c nghim l
A. (2;1) B. (3;2) C. (0;1) D. (1;2) .
Cu 3 . Sin300 bng
B. C. D. .
Cu 4 . T gic MNPQ ni tip ng trn (O) . Bit gc MQP c s o l
A.1300 B.1200 C.1100 D.1000 .
Phn II . T lun ( 8im )
Cu 1 . Cho biu thc A = .
a ) Nu KX v rt gn A .
b ) Tm tt c cc gi tr ca x sao cho A < 0 .
c ) Tm tt c cc g tr ca tham s m phng trnh A c nghim
Cu 2 . Hai xe my khi hnh cng mt lc i t A n B . Xe my th nht c vn tc trung bnh ln hn vn tc trung bnh ca xe my th hai 10km/h , nn n trc xe my th hai 1 gi . Tnh vn tc trung bnh ca mi xe my bit rng qung ng AB di 120 km .
Cu 3 . Cho na ng trn tm O , ng knh AB . im H nm gia A v B ( H khng trng vi O ) . ng thng vung gc vi AB ti H , ct na ng trn trn ti im C . Gi D v E ln lt l chn cc ng vung gc k t H n AC v BC .
a ) T gic HDCE l hnh g ? V sao ?
b ) Chng minh ADEB l t gic ni tip .
c ) Gi K l tm ng trn ngoi tip t gic ADEB . Chng minh DE = 2KO .
.................................................................Ht .................................................................S GD&T NGH AN K THI TUYN SINH VO LP 10THPT
NM HC 2008 2009
Mn : Ton
Thi gian : 120 pht
I . PHN TRC NGHIM : (2,0 im)
Em hy chn mt phng n tr li ng trong cc phng n (A, B, C, D ) ca tng cu sau ri ghi phng n chn vo bi lm .
Cu 1 . (0,5 im)
th hm s y = -3x + 4 I qua im :
A. (0;4) B.(2;0) C(-5;3) D. (1;2)
Cu 2 . (0,5 im)
bng :
A. -7 B. -5C. 7
D. 5
Cu3 . (0,5 im)
Hnh trn bn knh 4cmth c din tch l :
A. 16 (cm2)B. 8 (cm2) C.4 (cm2) D.2 (cm2)
Cu4 . Tam gic ABC vung A , bit tgB = v AB = 4 . di cnh AC l :
A. 2
B. 3
C. 4
D. 6
II . PHN T LUN : (8 im)
Cu1. (3im)
Cho biu thc : P =
a. Nu iu kin xc nh v rt gn biu thc P .
b. Tm cc gi tr ca x P = .
c. Tm gi tr nh nht ca biu thc M = .
Cu 2 . (2,0 im)
Hai ngi th cng qut sn cho mt ngi nh trong 2 ngy th xong vic . Nu ngi th nht lm trong 4 ngy ri ngh v ngi th hai lm tip trong 1 ngy th xong vic . Hi mi ngi lm mt mnh th bao lu s xong vic ?
Cu 3 . (3,0 im)
Cho tam gic ABC vung A . ng trn ng knh AB ct BC ti M . Trn cung nh AM ly im E ( ) . Ko di BE ct AC ti F .
a. Chng minh , t suy ra MEFC l mt t gic ni tip .
b. Gi K l giao im ca ME v AC . Chng minh AK2 = KE.KM .
c. Khi im E v tr sao cho AE + BM = AB . chng minh rng giao im cc
ng phn gic ca v thuc on thng AB .
. Ht S GD & T NGH AN K THI TUYN SINH VO LP 10 THPT
NM HC 2009 - 2010
Mn thi : Ton . Thi gian : 120 pht
Cu 1 (3,0 im ) . Cho biu thc A = .
a) Nu iu kin xc nh v rt gn A .
b) Tnh gi tr ca biu thc A khi x = .
c) Tm tt c cc gi tr ca x A < 1 .
Cu 2 (2,5 im ) . Cho phng trnh bc hai vi tham s m : 2x2 + ( m + 3 )x + m = 0 (1).
a) Gii phng trnh khi m = 2 .
b) Tm cc gi tr ca tham s m phng trnh (1) c hai nghim x1 , x2 tho mn
=
c) Gi x1 , x2 l hai nghim ca phng trnh (1) . Tm gi tr nh nht ca biu thc
P = .
Cu3 ( 1,5 im ) . Mt tha rung hnh ch nht c chiu rng ngn hn chiu di 45m . Tnh din tch tha rung , bit rng nu chiu di gim 2 ln v chiu rng tng 3 ln th chu vi tha rung khng thay i .
Cu 4 ( 3,0 im ) . Cho ng trn ( O ; R ) , ng knh AB c nh v CD l mt ng knh thay i khng trng vi AB . Tip tuyn ca ng trn ( O ; R ) ti B ct ng thng AC v AD ln lt ti E v F .
a) Chng minh rng BE.BF = 4R2 .
b) Chng minh t gic CEFD ni tip c ng trn .
c) Gi I l tm ng trn ngoi tip t gic CEFD . Chng minh tm I lun nm trn mt ng thng c nh .
.......................................................... Ht..............................................................................
S GIO DC V O TO K THI TUYN SINH VO LP 10 THPT
NGH AN Nm hc 2010 - 2011
Mn thi : Ton
Thi gian: 120 pht Cu I (3,0 im). Cho biu thc A = .
1. Nu iu kin xc nh v rt gn biu thc A.
2. Tnh gi tr ca biu thc A khi x = 9.
3. Khi x tho mn iu kin xc nh. Hy tm gi tr nh nht cu biu thc B,
vi B = A(x-1).
Cu II (2,0 im). Cho phng trnh bc hai sau, vi tham s m:
x2 - (m + 1)x + 2m - 2 = 0 (1)
1. Gii phng trnh (1) khi m = 2.
2. Tm gi tr ca tham s m x = -2 l mt nghim ca phng trnh (1).
Cu III (1,5 im). Hai ngi cng lm chung mt cng vic th sau 4 gi 30 pht h lm xong cng vic. Nu mt mnh ngi th nht lm trong 4 gi, sau mt mnh ngi th hai lm trong 3 gi th c hai ngi lm c 75% cng vic.
Hi nu mi ngi lm mt mnh th sau bao lu s xong cng vic? (Bit rng nng sut lm vic ca mi ngi l khng thay i).
Cu IV (3,5 im). Cho na ng trn tm O ng knh AB. im H c nh thuc on thng AO (H khc A v O). ng thng i qua im H v vung gc vi AO ct na ng trn (O) ti C. Trn cung BC ly im D bt k (D khc B v C). Tip tuyn ca na ng trn (O) ti D ct ng thng HC ti E. Gi I l giao im ca AD v HC.
1. Chng minh t gic HBDI ni tip ng trn.
2. Chng minh tam gic DEI l tam gic cn.
3. Gi F l tm ng trn ngoi tip tam gic ICD. Chng minh gc ABF c
s o khng i khi D thay i trn cung BC (D khc B v C).
--------------Ht-------------
S GIO DC V O TO
NGH ANK THI TUYN SINH VO LP 1 THPT
NM HC 2011 2012
Cu 1: (3,0 im)
Cho biu thc A =
a) Nu iu kin xc nh v rt gn biu thc A
b) Tim gi tr ca x A = .
c) Tm gi tr ln nht cua biu thc P = A - 9
Cu 2: (2,0 im)
Cho phng trnh bc hai x2 2(m + 2)x + m2 + 7 = 0 (1) (m l tham s)
a) Gii phng trnh (1) khi m = 1.
b) Tm m phng trnh (1) c nghim x1, x2 tha mn Cu 3: (1,5 im)
Qung ng AB di 120 km. Hai xe my khi hnh cng mt lc i t A n B. Vn tc ca xe my th nht ln hn vn tc ca xe my th hai l 10 km/h nn xe my th nht n B trc xe my th hai 1 gi. Tnh vn tc ca mi xe ?
Cu 4: (3,5 im)
Cho im A nm ngoi ng trn (O). T A k hai tip tuyn AB, AC v ct tuyn ADE ti ng trn (B, C l hai tip im; D nm gia A v E). Gi H l giao im ca AO v BC.
a) Chng minh rng ABOC l t gic ni tip
b) Chng minh rng AH.AO = AD.AE
c) Tip tuyn ti D ca ng trn (O) ct AB, AC theo th t ti I v K. Qua im O k ng thng vung gc vi OA ct tia AB ti P v ct tia AC ti Q.
Chng minh rng IP + KQ PQ.
----- Ht ------
Cu 1: (3,0 im)
a). iu kin
Vi iu kin , ta c:
b). A = th (tha mn iu kin)
Vy th A =
c). Ta c P = A - 9 =
p dng bt ng thc C si cho hai s dng ta c:
Suy ra: . ng thc xy ra khi
Vy gi tr ln nht ca biu thc khi
Cu 2: (2,0 im)
a). Gii phng trnh (1) khi m = 1.
Khi m = 1 ta c phng trnh:
Vy phng trnh c hai nghim v
c) phng trnh (1) c nghim x1, x2 th
(*)
Theo nh l Vi t ta c:
Theo bi ra x1x2 2(x1 + x2) = 4 ta c:
EMBED Equation.DSMT4i chiu iu kin (*) ta c m = 5 l gi tr cn Tm.
Cu 3: (1,5 im)
Gi vn tc ca xe my th hai l
Vn tc ca xe my th nht l
thi gian xe my th hai i ht Q AB l: 120/x
thi gian xe my th nht i ht Q AB l :120/x+10
Theo bi ra ta c phng trnh:
EMBED Equation.DSMT4i chiu iu kin ta c x = 30.
Vy vn tc ca xe th nht l 40 (km/h) v vn tc ca xe th hai l 30 (km/h)
Cu 4:
a) V AB, AC l tip tuyn ca (O) nn
Suy ra
Vy t gic ABOC ni tip.
b) Ta c ABO vung ti B c ng cao BH, ta c :
AH.AO = AB2 (1)
Li c ABD AEB (g.g)
EMBED Equation.DSMT4 AB2 = AD.AE (2)
T (1), (2) suy ra:
AH.AO = AD.AE
c). Xt tam gic v
Ta c (V tam gic APQ cn ti A)
v
Ta c: (3)
Li c:
Suy ra (4)
T (3), (4) suy ra :
Do (g.g)
T suy ra IP.KQ = OP.OQ = hay PQ2 = 4.IP.KQ
Mt khc ta c: 4.IP.KQ (IP + KQ)2 (V )
Vy .
CHNH THC
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