(本題12分)已知函數(shù)
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.
(1)當不等式
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的解集為
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時,求實數(shù)
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的值;
(2)若
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,且函數(shù)
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在區(qū)間
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上的最小值是
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,求實數(shù)
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的值。
解:(1)由
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(2)
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,對稱軸為
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當
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即
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時,
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,顯然不合題意;
當
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即
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時,
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,解得
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,符合題意;
當
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即
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時,
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,得
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,不合題意。
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