已知集合A={x|x
2-6x+8<0},B={x|(x-a)(x-3a)<0};
(1)若A⊆B,求a的取值范围;
(2)若A∩B={x|3<x<4},求a的取值范围.
考点分析:
相关试题推荐
给出定义:若m-
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321016_ST/0.png)
<x≤m+
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321016_ST/1.png)
(其中m为整数),则m叫做离实数x最近的整数,记作{x}=m.在此基础上给出下列关于函数f(x)=|x-{x}|的四个命题:
①函数y=f(x)的定义域为R,值域为[0,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321016_ST/2.png)
];
②函数y=f(x)的图象关于直线x=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321016_ST/3.png)
(k∈Z)对称;
③函数y=f(x)是周期函数,最小正周期为1;
④函数y=f(x)在[-
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321016_ST/4.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321016_ST/5.png)
]上是增函数.
其中正确的命题的序号
.
查看答案
已知函数f(x)=x
3+x,对任意的m∈[-2,2],f(mx-2)+f(x)<0恒成立,则x的取值范围为
.
查看答案
函数f(x)定义域为R,x、y∈R时恒有f(xy)=f(x)+f(y),若f(
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321014_ST/0.png)
)+f(
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321014_ST/1.png)
)=2,则f(
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321014_ST/2.png)
)=
.
查看答案
设f(x)是定义在R上的奇函数,且y=f(x)的图象关于直线
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321013_ST/0.png)
对称,则f(1)+f(2)+f(3)+f(4)+f(5)=
.
查看答案
设集合
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103101006059432134/SYS201311031010060594321012_ST/0.png)
,B={x|log
4(x+a)<1},若A∩B=∅,则实数a的取值范围是
.
查看答案