满分5 >
初中数学试题 >
如图,直径为10的⊙A经过点C(0,5)和点O(0,0),B是y轴右侧⊙A优弧上...
如图,直径为10的⊙A经过点C(0,5)和点O(0,0),B是y轴右侧⊙A优弧上一点,则∠OBC的正弦值为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999012_ST/images0.png)
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999012_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999012_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999012_ST/2.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999012_ST/3.png)
考点分析:
相关试题推荐
下面四个几何体中,俯视图为四边形的是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999011_ST/images0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999011_ST/images1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999011_ST/images2.png)
D.
查看答案
某市6月上旬前5天的最高气温如下(单位:℃):28,29,31,29,32.对这组数据,下列说法正确的是( )
A.平均数为30
B.众数为29
C.中位数为31
D.极差为5
查看答案
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999009_ST/images0.png)
如图,在直角三角形ABC中(∠C=90°),放置边长分别3,4,x的三个正方形,则x的值为( )
A.5
B.6
C.7
D.12
查看答案
下列运算正确的是( )
A.a
2+a
3=a
5B.(a-2)
2=a
2-4
C.2a
2-3a
2=-a
2D.(a+1)(a-1)=a
2-2
查看答案
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999007_ST/images0.png)
在平面直角坐标系中,⊙P的圆心是(2,a)(a>2),半径为2,函数y=x的图象被⊙P截得的弦AB的长为
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190251932299988/SYS201311011902519322999007_ST/0.png)
,则a的值是
.
查看答案