TRUONG THPT BA.O
DUY Tit
Mt .?\\~
~
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(OOJ
BE THI TOO B~I HQC BQ'T VI (2008 - 2009)
MoD: TOA.N; Kh8i A.
Thai gian lam hai: 180philt, kh6ng kd thai gian phat dJ
* * * ------------
Can I. Choham s6
y
=
x3 +ax2 +bx+c.
1. Khflosat S\1'bi€n thien va ve db thi cua ham s6 khi a = 3,b = 0,
c
=
-4
.
2. ChUngminh r~ng di~u ki~n cAnva du d€ db thi ham s6 c~t tI1)Choanh t~i hai di€m
d6i xung nhau qua g6c tQadQla ab = c v6'i b < O.
Can II.
1. Gifliphuang trinh:
1+ 2 .Jx - x2
=
-rx + .J1- x
.
3
2. Gifliphuang trinh:
sin2x+ sin23X(cOS3xsin3x+sin3xcos3x)=sinxsin23x.
3sin4x
. 2
C
"
III
Tinhd
"" ,
hhinh h
~
d
"'
h b
'. ,
d
' 2
x
,
27
an. I~ntIC p ang uQ'cglal ~ 01cac uang y
=
x ,y =
8
va y
=--;.
Can IV. Cho tU di~n ABCD, trong d6 BC = a, AB = AC = b, DB = DC = c, a la g6c
ph~ng OOidi~n c~nh BC (a < ~). V6'i di~u ki~n nao cua b, c thi duemg th~g n6i trung
di€m E ctia BC vai trung di€m F ctia AD la duemgvuong g6c chung ctia BC va AD?
V6'idi~uki~n vila tim duQ'chay tiOOth€ tich tUdi~n ABCD.
Can V. Cho x, y, z la ba s6 duang th6a man xyz = 1. ChUngminh r~g:
x2 y2 z2 3
-+-+-;;::-.
l+y l+z l+x 2
Can VI. Trang khong gian v6'i h~tQadQl)~ cac vuong g6c Oxyz cho
m~t cAll x2 + y2 + z2
=
4 (8)
vam~tph~g x+z=2 (P).
1. Chung minh r~ng m~t ph~ng (P) c~t m~t cAll(8). Xac dinh tQadQtam va tinh ban
&im ctia duemgtrim (C) la giao tuy€n gifi'a(P) va (8).
2. Vi€t phuang trinh duemg cong (CI) la hinh chi€u vuong g6c ctia (C) tren m~t
ph~ng tQadQOxy.
Can VII. Tu cac chfi's6 1, 2, 3, 4, 5, 6, 7, 8, 9 c6 th€ l~p duQ'cbaa nhieu s6 t\1'nhien
m6i s6 gbm 6 chfi' s6 khac nhau va tAng cua cac chu s6 hang chl,lc,hang tram, hang
nghin b~ng 8?
Giam
thi coi thi kh6ng giai thiGhgi them
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