纳米材料与锂电池:3道初一的题(被选中答案追加10分悬赏分)

来源:百度文库 编辑:查人人中国名人网 时间:2024/05/05 15:56:52
1.已知X满足不等式3(5X+2)+5>4X-6(X+1),化简|X+1|-|1-3X|=____.

2.(X+1)/3大于等于X-[(X-1)/2] (1)
3(X-2)+8>2X (2)

3.3X+2大于等于3-(1-X) (1)
1-[(X-1)/2]>[(X+2)/3]-X

第2,3题大家能不能给个详细过程啊......

1. -1<x<=1/3 : |x+1|-|1-3x|=4x
x>1/3 : |x+1|-|1-3x|=2-2x

2.(1) (x+1)/3 >= x-(x-1)/2
2(x+1)>= 6x-3(x-1)
2x+2>= 6x-3x+3
x<=-1

(2) 3(x-2)+8>2x
3x-6+8>2x
x>-2

==> -2<x<=-1

3.(1) 3x+2>=3-(1-x)
3x+2>=3-1+x
2x>=0
x>=0

(2) 1-(x-1)/2>(x+2)/3-x
6-3(x-1)>2(x+2)-6x
6-3x+3>2x+4-6x
x>-5

我四年没学过数学了不好意思~