题目内容
15.设α:x≥1或x≤-5,β:x≥-2m+1或x≤2m-3,m∈R,若β是α的必要非充分条件,则实数m的取值范围为[0,+∞).分析 根据β是α的必要非充分条件,得到不等式组,解出即可.
解答 解:若β是α的必要非充分条件,
则α⇒β,
∴$\left\{\begin{array}{l}{2m-3≥-5}\\{-2m+1<1}\end{array}\right.$或$\left\{\begin{array}{l}{2m-3>-5}\\{-2m+1≤1}\end{array}\right.$,
解得:m≥0,
故答案为:[0,+∞).
点评 不同考查了充分必要条件,考查不等式问题,是一道基础题.
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