5.已知各项不为0的等差数列{an}.满足2a3-a+2a11=0.数列{bn}是等比数列.且b7=a7.则b6b8等于( ) A.2 B.4 C.8 D.16 解析:由题意可知.b6b8=b=a=2(a3+a11)=4a7. ∵a7≠0.∴a7=4.∴b6b8=16. 答案:D 查看更多

 

题目列表(包括答案和解析)

已知各项不为0的等差数列{an},满足2a3-a12=0,a1=d,数列{bn}是等比数列,且b13=a2,b1=a1则b6b8(  )

查看答案和解析>>

已知各项不为0的等差数列{an},满足2a3-a12=0,a1=d,数列{bn}是等比数列,且b13=a2,b1=a1则b6b8( )
A.72
B.4
C.8
D.16

查看答案和解析>>

已知各项不为0的等差数列{an},满足2a3-a12=0,a1=d,数列{bn}是等比数列,且b13=a2,b1=a1则b6b8


  1. A.
    72
  2. B.
    4
  3. C.
    8
  4. D.
    16

查看答案和解析>>

已知各项不为0的等差数列{an},满足2a3-a27+2a11=0,数列{bn}是等比数列,且b7=a7,则b6b8等于
[     ]
A.2
B.4
C.8
D.16

查看答案和解析>>

已知各项不为0的等差数列{an},满足,数列{bn}是等比数列,且b7=a7,则b6b8

[  ]
A.

2

B.

4

C.

8

D.

16

查看答案和解析>>


同步练习册答案