【新高考數(shù)學】小題壓軸題專練7 基本不等式

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

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y

x2

x311x2322x2

3x22x3Ca

a

1

()A1B

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C

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DbR

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s)

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s

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y滿xy

xyxy

)A

B

C

D

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1616ststtt

14164()(4()7st7tt

164151t7

s4tstsB

nmnmmnm2

mn(m

)A

176

B

145

C

D

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mn(m(n1mmmn

11(n2))5

nm()m

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y(x[xyxy)xy

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2

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2

2

xy

xy

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1242b

A

720

B

720

C

7620

D

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1b6(11b)7)20bb20

6(11)

15476ba64Cxyyx

1|(2|x|y

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B

C

D

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322

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n(

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0R

12(11

)A

1023

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43

C

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b

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a

b

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a

2

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22

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24

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28