数学题︳x+3︳+︳x-2︳﹤7 求x的取值范围
问题描述:
数学题︳x+3︳+︳x-2︳﹤7 求x的取值范围
答
分区间讨论
x|x+3|+|x-2|
= -(x+3)-(x-2)
= -2x -1
==>
x>-4
==>
-4
=(x+3)-(x-2)
=5
符合,所以,
-32
=x+3+x-2
=2x+1
==>
x==>
2
-4