满分5 >
高中数学试题 >
给出下列四个命题:①=,②α,β都是第三象限角,若cosα>cosβ,则sinα...
给出下列四个命题:①
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580011_ST/0.png)
=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580011_ST/1.png)
,②α,β都是第三象限角,若cosα>cosβ,则sinα>sinβ,③对于两个变量之间的相关系数r,|r|≤1且|r|越接近于1,相关程度越大;|r|越接近于0,相关程度越小;④设O为坐标原点,A(1,1),若点B满足
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580011_ST/2.png)
,则
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580011_ST/3.png)
的最小值为2+
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580011_ST/4.png)
.其中正确的命题的个数是( )
A.0
B.1
C.2
D.3
考点分析:
相关试题推荐
从编号为,1,2,3,4,5,6,的六的小球中任取4个,放在标号为A,B,C,D的四个盒子里,每盒一球,且2号球不能放在B盒中,4号球不能放在D号盒中,则不同的放法种( )
A.96
B.180
C.252
D.280
查看答案
已知F
1、F
2分别是双曲线
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580009_ST/0.png)
(a>0,b>0)的左、右焦点,P为双曲线上的一点,若∠F
1PF
2=90°,且△F
1PF
2的三边长成等差数列,则双曲线的离心率是( )
A.2
B.3
C.4
D.5
查看答案
如图,在△ABC中,AB=5,BC=3,CA=4,且O是△ABC的外心,则
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580008_ST/0.png)
=( )
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580008_ST/images1.png)
A.6
B.-6
C.8
D.-8
查看答案
程序框图(算法流程图)如图所示,其输出结果A=( )
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580007_ST/images0.png)
A.15
B.31
C.63
D.127
查看答案
已知F
1,F
2是椭圆的两个焦点,过F
1且与椭圆长轴垂直的直线交椭圆于A,B两点,若△ABF
2是正三角形,则这个椭圆的离心率是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580006_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580006_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104358062/SYS201310241826461043580006_ST/2.png)
D.
查看答案