小題壓軸題專練7基本不等式一、單選題x

11xx

xy()A2B

1C32

D4

11xx

33x

112y(4[(3x)]22

31[(3y)22x2

1x)x31[4]2x

332x

33

13y23

y

x2

x311x2322x2

3x22x3Ca

a

1

()A1B

65

C

22

DbR

ab

ab

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tab)4abt(tt(s4)t

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s)

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s

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y滿xy

xyxy

)A

B

C

D

yxxyx(s(tttxytstst

1616ststtt

14164()(4()7st7tt

164151t7

s4tstsB

nmnmmnm2

mn(m

)A

176

B

145

C

D

83m2mn(

(2)

mn(m(n1mmmn

11(n2))5

nm()m

nm1m1214()mn5mn55

1n2

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52()A

B

C

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y(xx

y(x[xyxy)xy

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2

(22)xy

2

2

xy

xy

16Dl2xyP(l()

1242b

A

720

B

720

C

7620

D

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2ba4a(3b5)

26a2bb16b)(9)]()119b

1b6(11b)7)20bb20

6(11)

15476ba64Cxyyx

1|(2|x|y

)A

B

C

D

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b

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b

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bb

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22

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2b

bbbDab

2

(

)A

322

B

322

C

322

D

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2

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ab

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ffaf2fa2f(42)

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2)

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xy

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n(

nn2)(n((n

f0n2mf()mC14bax

0R

12(11

)A

1023

B

43

C

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a4aB152a

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()A4

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D

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b

acos

22

r

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2sin

r(

rsin(33A17ac

abc()Aa

b

B

Ca

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b

a

b

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2c

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a

a

2

)

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ba

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332

a

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b

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(b2(1)()2(1)(b)

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(

a，b2

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1

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bc3c

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a

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t

3b

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b

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bab(a9)(b4)4ab)

ab)24(18)288

tab1218ab

t

tt288

t18)

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12(288t288)

t2t122)t2y

t

tt288

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22

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65

22

24

ba

2

2

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3

32

b

f

(3)

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2

2

2

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tt3]25y

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2xyxyxyxyyxyy

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t

xyy

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