题目内容
1.不等式组$\left\{\begin{array}{l}{-2x≤x+6}\\{7-x>1}\end{array}\right.$的整数解解集为{-2,-1,0,1,2,3,4,5};不等式x2-1<3的解用区间表示为(-2,2).
分析 ①不等式组$\left\{\begin{array}{l}{-2x≤x+6}\\{7-x>1}\end{array}\right.$,化为$\left\{\begin{array}{l}{x≥-2}\\{x<6}\end{array}\right.$,解得-2≤x<6,即可得出整数解解集.
②利用一元二次不等式的解法即可得出.
解答 解:①不等式组$\left\{\begin{array}{l}{-2x≤x+6}\\{7-x>1}\end{array}\right.$,化为$\left\{\begin{array}{l}{x≥-2}\\{x<6}\end{array}\right.$,解得-2≤x<6,整数解解集为{-2,-1,0,1,2,3,4,5}.
②不等式x2-1<3,x2<4,解得-2<x<2,因此解集为(-2,2).
故答案为:{-2,-1,0,1,2,3,4,5},(-2,2).
点评 本题考查了一元二次不等式的解法、不等式组的解法,考查了推理能力与计算能力,属于基础题.
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