若
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000527523180678/SYS201311030005275231806011_ST/0.png)
,则a的取值范围是
.
考点分析:
相关试题推荐
如图,在△ABC中,已知∠C=90°,BC=6,AC=8,则它的内切圆半径是( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000527523180678/SYS201311030005275231806009_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000527523180678/SYS201311030005275231806009_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000527523180678/SYS201311030005275231806009_ST/1.png)
C.2
D.1
查看答案
两圆的圆心坐标分别是(
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000527523180678/SYS201311030005275231806008_ST/0.png)
,0)和(0,1),它们的半径分别是3和5,则这两个圆的位置关系是( )
A.相离
B.相交
C.外切
D.内切
查看答案
如图,⊙O的半径为5,弦AB的长为8,M是弦AB上的动点,则线段OM长的最小值为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131103000527523180678/SYS201311030005275231806007_ST/images0.png)
A.2
B.3
C.4
D.5
查看答案
一个等边三角形绕其旋转中心至少旋转( )度,才能与自身重合.
A.30°
B.60°
C.120°
D.180°
查看答案