Question

跪求准确答案，重金悬赏

Answer 1

追答

Answer 2

解几个吧
1)x^2+5x+6>0
(x+2)(x+3)>0
x>-2或x<-3
5)x^2-x-12<=0
(x-4)(x+3)<=0
-3<=x<=4
12)2x^2+15x+7<=0
(2x+1)(x+7)<=0
-7<=x<=-1/2
13)2x^2+11x+12>=0
(2x+3)(x+4)>=0
x>=-3/2或x<=-4

Answer 3

1，x<-3，x>-2
2，-1≤x≤6

追答

3，-4<x<-3
4，x≤1，x≥6

5，-33

7，x≤2，x≥6
8，-2<x<6

9，x4/3
10，x2/3

11，x12
12，-7≤x≤-1/2

13，x≤-3/2，x≥4
14，x10/3

15，2x²-6x+5>0
x²-3x+5/2>0
x²-3x+9/4-9/4+5/2>0
(x-3/2)²+1/4>0
x取任何值，不等式都成立
即，-∞<x<+∞