题目内容
3.解不等式组$\left\{\begin{array}{l}{1-3(x-1)≤8-x}\\{\frac{x+3}{2}+\frac{x-1}{3}>x+1}\end{array}\right.$并把解集表示在数轴上.分析 先求出每个不等式的解集,再求出不等式组的解集即可.
解答 解:$\left\{\begin{array}{l}{1-3(x-1)≤8-x①}\\{\frac{x+3}{2}+\frac{x-1}{3}>x+1②}\end{array}\right.$
∵解不等式①得:x≥-2,
解不等式②得:x<1,
∴不等式组的解集为-2≤x<1,
在数轴上表示为:
.
点评 本题考查了解一元一次不等式组和在数轴上表示不等式组的解集,能根据不等式的解集求出不等式组的解集是解此题的关键.
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