在△ABC中,角A、B、C所对的边分别为a,b,c,已知cos2C=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908016_ST/0.png)
.
(I)求sinC的值;
(Ⅱ)当a=2,2sinA=sinC时,求b及c的长.
考点分析:
相关试题推荐
函数
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908015_ST/0.png)
的图象为C,如下结论中正确的是
.(写出所有正确结论的编号)
①图象C关于直线
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908015_ST/1.png)
对称;
②图象C关于点
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908015_ST/2.png)
对称;
③函数f(x)在区间
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908015_ST/3.png)
内是增函数;
④由y=3sin2x的图角向右平移
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908015_ST/4.png)
个单位长度可以得到图象C.
查看答案
已知球O的表面积为16π,且球心O在60°的二面角α-l-β内部,若平面α与球相切于M点,平面β与球相截,且截面圆O
1的半径为
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908014_ST/0.png)
,P为圆O
1的圆周上任意一点,则M、P两点的球面距离的最值为
.
查看答案
已知{a
n}是等比数列,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908013_ST/0.png)
=
.
查看答案
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908012_ST/0.png)
展开式中不含 x
4项的系数的和为
.
查看答案
设双曲线的-个焦点为F;虚轴的-个端点为B,如果直线FB与该双曲线的一条渐近线垂直,那么此双曲线的离心率为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908011_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908011_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519090834/SYS201311012251575190908011_ST/2.png)
D.
查看答案