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问题: 解不等式组!!!!

1.{3(x-1)+13>5x-2(5-x),5-(2x+1)<3-6x~~~~~~~~~~~~~~~~~~2.{-3(x-2)大于或等于4,三分之1+2x>x-1

解答:

1)3(x-1)+13>5x-2(5-x)
--->3x-3+13>5x-10+2x
--->3x+10>7x-10
--->-4x>-20
--->x<(-20)/(-4)=5
5-(2x+1)<3-6x
--->5-2x-1<3-6x
--->4x<-1
--->x<-1/4
取交集得x<-1/4.
2)-3(x-2)>=4
--->-3x+6>=4
--->-3x>=-2
--->x=<2/3
(1+2x)/3>x-1
去分母1+2x>3x-3
--->-x>-4
--->x<4
取交集 x=<2/3.