ĐỀ KHẢO SÁT TRƯỚC KÌ THI ĐẠI HỌC NĂM 2010


TRƯNG THPT TRC NINH B
ĐỀ KHO ST TRƯC K THI ĐI HỌC NĂM 2010
Môn: Toán !"#$%&'
Bài 1(2 điểm):
!' ()*+,&+-.&/00123&4'56+7
8 8
9 9 !' :9 9 !'y x x= + −
8' ;&</&<=5*>2?&@2?2ABC2DE5&.$&FG.$HI&2.':
Bài 2(3 điểm):
!' )I$DJ&<; 
8 8
!
8
8
 !' 8' K
x y
x y
xy x y x y

+ +
=

+ +


− − + + − =


Lx y R
∈

'
8' )$DJ&<; 
8 8
+ :& 5*+ 5*+8 :8 & 'x x x x x+ = −
L0M
x R
∈
'
N' ;&-52?$DJ&<;+F5AI&-5&<*2*O
P
QR
8
 
 
 


8 8
!S 8 !S8
!
 !':*  8' R P'* R R #
8
m x m m
x
− − + − + − =
−
Bài 3(1 điểm):
*&TUIV5A&,5V0FW5H2XVLVYQ5,55O
NSA SB SC a= = =
LZ#':

</5OLV[DE&\G2?L+*5*YVY:]&?&]5B75A$:V
&^*:
Bài 4(2 điểm):
!']&]5$H 
!
8 8
#
:! 'x x dx
+
∫
8'<*_&$`&*O2axy 5*2?NQ!':bc$$DJ&<;2D&`UdF05e&
5fFUDJ5,5&<=5&g2axLy&T&-&OhLi+*5*UI&]5&,5hij\&:
Bài 5(1 điểm):
<*BW0MI&g2akGl5*2D&`U
!

!
! 8 Q '
! 8
x t
y t t R
z t
= +


= + ∈


= +


L2D&`U
8

*&FG.56_&$`h' 8kmGm!Y#0i' 8knGn8lmPY#:g*2?56
U!0U
8
:o.&$DJ&<;2D&`U
N
dF8QNQ!'L23&5e&2D&`U
!
0U
8
[
DE&&OV0+*5*&,5V5H2X:
Bài 6(1 điểm):
*x, y, z
#≥
0
8 8 8
Nx y z+ + =
:T
N N N
8 8 8
N 8
8
! ! !
x y z
y z x
+ + ≥
+ + +

::::::::::::::::::.&::::::::::::::::::

TRƯNG THPT TRC NINH B
KHO ST TRƯC K THI ĐI HỌC NĂM 2010
Môn: Toán !"#$%&'
Đáp n vắn tắt:
V!
!'
!
2?
aUF ?
pA+7 
8 8
9 9 !' :9 9 !'y x x= + − ⇔
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R
q8k
8
n!'
pr sQ
 Q 
x x
y y
→−∞ →+∞
= +∞ = +∞
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N
t R R Q t # #Q !y x x y x x= − = ⇔ = = ±
pVV  #:8P
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po12%2&4 #:8P
8'
!
2?
pg #'
Ox∈
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pD&`U2dF0MI+7A5B5A$DJ&<; GYBkq'
pU&&56'B05XBI$&+F5AI
R 8
N
8 !  '
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R R
x x k x a
I
x x k

− + = −

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
#:8P
pA
8
#
 '  '
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k
I A

x
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⇔
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
*_5
8
8
R  !'
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N R ! #!'
x x k
B
x ax

− =


− + =


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p@I'L5X5*&a&&.$&FG.UFG\&U! GY#:ocG2?&@BC2DE5N
&.$&FG.$&M'5[026IV'$)5A8I$kQB'0MkB,5
!
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8 8
a a− ≠ < − ≠ >hoÆc
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aUF ?
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2?
pI
8 8
 !'  !' P
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x y
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
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⇔

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
:_&
!
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u x
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

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
L&F2DE5I
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

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
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⇔ − − − − − + − =
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p_&
[ ]
!S 8
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8
t x x t
 
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2?
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