已知x满足2（log2x）^2+7log2x+3小于等于0,求x的取值范围.
<p>问题：已知x满足2（log2x）^2+7log2x+3小于等于0,求x的取值范围.<p>答案：↓↓↓<p class="nav-title mt10" style="border-top:1px solid #ccc;padding-top: 10px;">史震的回答：<div class="content-b">网友采纳 设log2x=t 2t^2+7t+3≤0 (2t+1)(t+3)≤0 -3≤t≤-1/2 -log28≤log2x≤-log2√2 log21/8≤log2x≤-log2√2/2 ∵底数＞1 ∴1/8≤x≤√2/2
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