-x2+7x-12 |
a |
x2+x+1 |
a |
x2+x+1 |
a |
21 |
a |
7 |
|
A.{x|0<x≤3} | B.R |
C.{x|x≤0,或x<3} | D.{x|x<-1,或x≥4} |
1 |
2 |
A.{x|-1≤x<2} | B.{x|-
| C.{x|x<2} | D.{x|1≤x<2} |
A.(-∞,-3) | B.(-3,1] | C.[1,2) | D.[2,3] |
1-x2 |
A.(-1,2) | B.[-1,2] | C.(-1,1] | D.(-1,1) |
A.(2,3] | B.(-∞,1]∪(2,+∞) | C.[1,2] | D.(-∞,0]∪[1,+∞) |
© 2017-2019 超级试练试题库,All Rights Reserved.