求A∩B,A∪B,A∩∁UB.
集合B={x|x2﹣4x+3>0}={x|x<1或x>3},
所以A∩B={x|﹣2<x<1},
A∪B={x|x<2或x>3},
∁UB={x|1≤x≤3},
所以A∩∁UB={x|1≤x<2}
Don't throw away some old things.We can____them.We can put our pens and pencils in____.They will be nice____.We can put flowers in some bottles;they will be nice____.We can stick some____together and put our cards in them.How interesting!
—You have been sitting on my hat and now it is badly _________.
—Sorry. I will ask my boss for _________ on my salary to buy you a new one.
某同学测得生活中常见物质的pH如下表,其中能使紫色石蕊试液变红的物质是 ( )
物质
牙膏
肥皂水
橘汁
草木灰水
食盐水
pH
8.2
9.2
3.5
10.6
7.0