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已知a>0,b>0,且a+2b=3,则2a+22b的最小值是 .
已知a>0,b>0,且a+2b=3,则2a+22b的最小值是 .
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定义max{a,b,c}为a、b、c中的最大者,令M=max{|1+a+2b|,|1+a-2b|,|2+b|},则对任意实数a,b,M的最小值是( )
A.1
B.
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D.2
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已知向量
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|=1,对任意t∈R,恒有|
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|≥|
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|,则( )
A.
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B.
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C.
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D.(
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+
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)
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