函數(shù)
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在區(qū)間
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上的最小值為
.
試題分析:∵
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,當且僅當
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即x=1時,等號成立,∴函數(shù)
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在區(qū)間

上的最小值為
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點評:當一個題目中同時出現(xiàn)多次使用基本不等式時,要注意等號成立的條件也成立
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
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