题目
题型:解答题难度:一般来源:不详
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(1)求x的取值范围;
(2)求函数f(x)=log2(
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答案
又log2x≥
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故所求x的取值范围是
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(2)f(x)=log2(
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=(log2x-1)•(log2x-2)=(log2x)2-3log2x+2
=(log2x-
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由已知
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所以,当log2x=
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当log2x=
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核心考点
举一反三
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