满分5 >
高中数学试题 >
等比数列{an}中,a5a14=5,则a8a9a10a11=( ) A.10 B...
等比数列{an}中,a5a14=5,则a8a9a10a11=( )
A.10
B.25
C.50
D.75
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/20131101225157519442834/SYS201311012251575194428001_ST/0.png)
( )
A.是偶函数
B.是奇函数
C.既是偶函数又是奇函数
D.既不是偶函数也不是奇函数
查看答案
设
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/0.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/1.png)
分别是与
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/2.png)
,
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/3.png)
向的单位向量,则下列结论中正确的是( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/4.png)
=
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/5.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/6.png)
-
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/7.png)
=1
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/8.png)
|+
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/9.png)
=2
D.|
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/10.png)
+
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225157519442834/SYS201311012251575194428000_ST/11.png)
|=2
查看答案
已知函数f(x)=-x
3+ax
2-4,a∈R.
(I)当a=3时,求f(x)在区间[-1,1]上的最大值和最小值;
(II )若存在x
∈(0,+∞),使得f(x
)>0,求a的取值范围.
查看答案
已知函数f(x)=log
4(4
x+1)+kx (x∈R)是偶函数.
(1)求k的值;
(2)若方程f(x)-m=0有解,求m的取值范围.
查看答案
已知函数f(x)=x
3+bx
2+ax+d的图象过点P(0,2),且在点M(-1,f(-1))处的切线方程为6x-y+7=0.
(Ⅰ)求函数y=f(x)的解析式;
(Ⅱ)求函数y=f(x)的单调区间.
查看答案