DE&DA Thi vao 10 HAI DUONG 2011

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Thi gian lm bi: 120 pht, không k thi gian giao đê
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20202

0


0

202

U/I≥1⇒0≥1B2

≥1⇒202

≥1P
#
0
#
≥20BQ'I≥1
dVe 5?J)!RI* cf *
# # # # # #
$ $ $
$
$ $ $a b b c c a
+ + ≤
+ + + + + +
BQ'II
37V ;<EE$
68
#
0
#
≥205?^BQEE$
⇒
#
0

#
0$≥200200⇒
( )
# #
$
$
abc c
a b ab a b c a b c
≤ =
+ + + + + +
6 p
# #
$
$
a
b c a b c
≤
+ + + +
B
# #
$
$
b
c a a b c
≤
+ + + +
U/8
# # # # # #
$ $ $
$

$ $ $
c b a a b c
a b b c c a a b c a b c a b c a b c
+ +
+ + ≤ + + = =
+ + + + + + + + + + + + + +