满分5 >
高中数学试题 >
将正三棱柱截去三个角(如图1所示A,B,C分别是△GHI三边的中点)得到几何体如...
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930518264/SYS201311031024209305182000_ST/images0.png)
将正三棱柱截去三个角(如图1所示A,B,C分别是△GHI三边的中点)得到几何体如图2,则该几何体按图2所示方向的侧视图(或称左视图)为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930518264/SYS201311031024209305182000_ST/images1.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930518264/SYS201311031024209305182000_ST/images2.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930518264/SYS201311031024209305182000_ST/images3.png)
D.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930518264/SYS201311031024209305182000_ST/images4.png)
考点分析:
相关试题推荐
设A(x
1,y
1),B(x
2,y
2)是椭圆
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/0.png)
,(a>b>0)上的两点,已知向量
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/1.png)
=(
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/2.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/3.png)
),
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/4.png)
=(
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/5.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/6.png)
),且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/7.png)
,若椭圆的离心率
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707021_ST/8.png)
,短轴长为2,O为坐标原点:
(Ⅰ)求椭圆的方程;
(Ⅱ)若直线AB过椭圆的焦点F(0,c),(c为半焦距),求直线AB的斜率k的值;
(Ⅲ)试问:△AOB的面积是否为定值?如果是,请给予证明;如果不是,请说明理由.
查看答案
已知函数f(x)=ax
2+1nx(a∈R).
(I)当
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707020_ST/0.png)
时,求f(x)在区间[1,e]上的最大值和最小值;
(II)如果在公共定义域D上的函数g(x),f
1(x),f
2(x)满足f
1(x)<g(x)<f
2(x),那么就称g(x)为f
1(x)、f
2(x)的“活动函数”,已知函数
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707020_ST/1.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707020_ST/2.png)
,若在区间(1,+∞)上,函数f(x)是f
1(x)、f
2(x)的“活动函数”,求实数a的取范围.
查看答案
已知圆C:(x-1)
2+y
2=9内有一点P(2,2),过点P作直线l交圆C于A、B两点.
(1)当l经过圆心C时,求直线l的方程;
(2)当弦AB被点P平分时,写出直线l的方程;
(3)当直线l的倾斜角为45°时,求弦AB的长.
查看答案
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707018_ST/images0.png)
如图,在直三棱柱ABC-A
1B
1C
1中,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707018_ST/0.png)
,M是棱BB
1的中点,N是CC
1的中点,AC
1与A
1N相交于点E.
(I)求三棱锥A-MNA
1的体积;
(II)求证:AC
1⊥A
1M.
查看答案
已知等比数列{a
n}中,a
2,a
3,a
4分别是某等差数列的第5项、第3项、第2项,且
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131103102420930270746/SYS201311031024209302707017_ST/0.png)
,公比q≠1.
(1)求数列{a
n}的通项公式;
(2)已知数列{b
n}满足:a
1b
1+a
2b
2+…+a
nb
n=2n-1(n∈N
*),求数列{b
n}的前n项和S
n.
查看答案