满分5 >
初中数学试题 >
如图,在纸上剪下一个圆形和一个扇形纸片,使之恰好能围成一个圆锥模型.若圆的半径为...
如图,在纸上剪下一个圆形和一个扇形纸片,使之恰好能围成一个圆锥模型.若圆的半径为r,扇形的半径为R,扇形的圆心角为90°,则
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860013_ST/0.png)
=
.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860013_ST/images1.png)
考点分析:
相关试题推荐
如图,四边形ABCD为矩形,△ACE为AC为底的等腰直角三角形,连接BE交AD、AC分别于F、N,CM平分∠ACB交BN于M,下列结论:(1)BE⊥ED;(2)AB=AF;(3)EM=EA;(4)AM平分∠BAC
其中正确的结论有( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860011_ST/images0.png)
A.1个
B.2个
C.3个
D.4个
查看答案
如图,在平面直角坐标系中,作第一象限角平分线OA,并依次作直角梯形,记第一个直角梯形的面积为S
1,前两个直角梯形的面积之和为S
2,前3个直角梯形的面积之和为S
3,…,前n个直角梯形的面积之和为S
n,则S
n与n之间的函数关系式为( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860010_ST/images0.png)
A.Sn=n
2+
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860010_ST/0.png)
n
B.Sn=n
2+
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860010_ST/1.png)
n+1
C.Sn=n
2+n
D.Sn=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860010_ST/2.png)
n
2+n+1
查看答案
如图,AB是⊙O的切线,切点为A,OB与⊙O交于C,且点C为OB的中点,过C点作弦CD使∠ACD=45°,弧AD的长为
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/0.png)
π,则以AD和AC的长为两根的一元二次方程是( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/images1.png)
A.x
2-(2+
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/1.png)
)x+2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/2.png)
=0
B.x
2-(2+
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/3.png)
)x-2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/4.png)
=0
C.x
2-(2-
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/5.png)
)x+2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/6.png)
=0
D.x
2-(2-
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/7.png)
)x-2
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131101190217890486011/SYS201311011902178904860009_ST/8.png)
=0
查看答案
用代数式表示“x的4倍与y的差的平方”正确的是( )
A.(4x-y)
2B.4x-y
2C.4(4x-y)
2D.(x-4y)
2
查看答案